/*-
 * See the file LICENSE for redistribution information.
 *
 * Copyright (c) 2002,2010 Oracle.  All rights reserved.
 *
 * $Id: RecoveryManager.java,v 1.242.2.5 2010/01/04 15:30:32 cwl Exp $
 */

package com.sleepycat.je.recovery;

import java.io.IOException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.logging.Level;
import java.util.logging.Logger;

import com.sleepycat.je.CacheMode;
import com.sleepycat.je.CheckpointConfig;
import com.sleepycat.je.DatabaseException;
import com.sleepycat.je.DbInternal;
import com.sleepycat.je.TransactionConfig;
import com.sleepycat.je.cleaner.RecoveryUtilizationTracker;
import com.sleepycat.je.config.EnvironmentParams;
import com.sleepycat.je.dbi.DatabaseId;
import com.sleepycat.je.dbi.DatabaseImpl;
import com.sleepycat.je.dbi.DbConfigManager;
import com.sleepycat.je.dbi.DbTree;
import com.sleepycat.je.dbi.EnvironmentImpl;
import com.sleepycat.je.latch.LatchSupport;
import com.sleepycat.je.log.CheckpointFileReader;
import com.sleepycat.je.log.FileManager;
import com.sleepycat.je.log.INFileReader;
import com.sleepycat.je.log.LNFileReader;
import com.sleepycat.je.log.LastFileReader;
import com.sleepycat.je.log.LogEntryType;
import com.sleepycat.je.tree.BIN;
import com.sleepycat.je.tree.ChildReference;
import com.sleepycat.je.tree.DIN;
import com.sleepycat.je.tree.IN;
import com.sleepycat.je.tree.Key;
import com.sleepycat.je.tree.LN;
import com.sleepycat.je.tree.MapLN;
import com.sleepycat.je.tree.Node;
import com.sleepycat.je.tree.SearchResult;
import com.sleepycat.je.tree.TrackingInfo;
import com.sleepycat.je.tree.Tree;
import com.sleepycat.je.tree.TreeLocation;
import com.sleepycat.je.tree.WithRootLatched;
import com.sleepycat.je.txn.BasicLocker;
import com.sleepycat.je.txn.LockResult;
import com.sleepycat.je.txn.LockType;
import com.sleepycat.je.txn.PreparedTxn;
import com.sleepycat.je.txn.Txn;
import com.sleepycat.je.utilint.DbLsn;
import com.sleepycat.je.utilint.Tracer;

public class RecoveryManager {
    private static final String TRACE_DUP_ROOT_REPLACE =
        "DupRootRecover:";
    private static final String TRACE_LN_REDO = "LNRedo:";
    private static final String TRACE_LN_UNDO = "LNUndo";
    private static final String TRACE_IN_REPLACE = "INRecover:";
    private static final String TRACE_ROOT_REPLACE = "RootRecover:";
    private static final String TRACE_IN_DEL_REPLAY = "INDelReplay:";
    private static final String TRACE_IN_DUPDEL_REPLAY = "INDupDelReplay:";
    private static final String TRACE_ROOT_DELETE = "RootDelete:";

    private EnvironmentImpl env;
    private int readBufferSize;
    private RecoveryInfo info;       // stat info
    private Map<Long, Long> committedTxnIds;  // committed txn ID to Commit LSN
    private Set<Long> abortedTxnIds;          // aborted txns
    private Map<Long, Txn> preparedTxns;     // txnid -> prepared Txn

    /* dbs for which we have to build the in memory IN list. */
    private Set<DatabaseId> inListBuildDbIds;

    private Set<DatabaseId> tempDbIds;       // temp DBs to be removed

    private Level detailedTraceLevel; // level value for detailed trace msgs
    private RecoveryUtilizationTracker tracker;

    /**
     * Make a recovery manager
     */
    public RecoveryManager(EnvironmentImpl env)
        throws DatabaseException {

        this.env = env;
        DbConfigManager cm = env.getConfigManager();
        readBufferSize =
            cm.getInt(EnvironmentParams.LOG_ITERATOR_READ_SIZE);
        committedTxnIds = new HashMap<Long, Long>();
        abortedTxnIds = new HashSet<Long>();
        preparedTxns = new HashMap<Long, Txn>();
        inListBuildDbIds = new HashSet<DatabaseId>();
        tempDbIds = new HashSet<DatabaseId>();
        tracker = new RecoveryUtilizationTracker(env);

        /*
         * Figure out the level to use for detailed trace messages, by choosing
         * the more verbose of the recovery manager's trace setting vs the
         * general trace setting.
         */
        detailedTraceLevel =
            Tracer.parseLevel(env,
                              EnvironmentParams.JE_LOGGING_LEVEL_RECOVERY);
    }

    /**
     * Look for an existing log and use it to create an in memory structure for
     * accessing existing databases. The file manager and logging system are
     * only available after recovery.
     * @return RecoveryInfo statistics about the recovery process.
     */
    public RecoveryInfo recover(boolean readOnly,
                                boolean replicationIntended)
        throws DatabaseException {

        info = new RecoveryInfo();

        try {
            FileManager fileManager = env.getFileManager();
            DbConfigManager configManager = env.getConfigManager();
            boolean forceCheckpoint =
                configManager.getBoolean
                (EnvironmentParams.ENV_RECOVERY_FORCE_CHECKPOINT);
            if (fileManager.filesExist()) {

                /*
                 * Establish the location of the end of the log. After this, we
                 * can write to the log. No Tracer calls are allowed until
                 * after this point is established in the log.
                 */
                findEndOfLog(readOnly);
                Tracer.trace(Level.CONFIG, env,
                             "Recovery underway, found end of log");

                /*
                 * Establish the location of the root, the last checkpoint, and
                 * the first active LSN by finding the last checkpoint.
                 */
                findLastCheckpoint();
                env.getLogManager().setLastLsnAtRecovery
                    (fileManager.getLastUsedLsn());
                Tracer.trace(Level.CONFIG, env,
                             "Recovery checkpoint search, " +
                             info);

                /* Read in the root. */
                env.readMapTreeFromLog(info.useRootLsn, replicationIntended);

                /* Build the in memory tree from the log. */
                buildTree();
            } else {

                /*
                 * Nothing more to be done. Enable publishing of debug log
                 * messages to the database log.
                 */
                env.enableDebugLoggingToDbLog();
                Tracer.trace(Level.CONFIG, env, "Recovery w/no files.");

                /* Enable the INList and log the root of the mapping tree. */
                env.getInMemoryINs().enable();
                env.logMapTreeRoot();

                /* Add shared cache environment when buildTree is not used. */
                if (env.getSharedCache()) {
                    env.getEvictor().addEnvironment(env);
                }

                /*
                 * Always force a checkpoint during creation.
                 */
                forceCheckpoint = true;
            }

	    int ptSize = preparedTxns.size();
            if (ptSize > 0) {
		boolean singular = (ptSize == 1);
		Tracer.trace(Level.INFO, env,
			     "There " + (singular ? "is " : "are ") +
			     ptSize + " prepared but unfinished " +
			     (singular ? "txn." : "txns."));

                /*
                 * We don't need this set any more since these are all
                 * registered with the TxnManager now.
                 */
                preparedTxns = null;
            }

            /*
             * Open the UP database and populate the cache before the first
             * checkpoint so that the checkpoint may flush file summary
             * information.  May be disabled for unittests.
             */
            if (DbInternal.getCreateUP
                (env.getConfigManager().getEnvironmentConfig())) {
                env.getUtilizationProfile().populateCache();
            }

            /* Transfer recovery utilization info to the global tracker. */
            tracker.transferToUtilizationTracker(env.getUtilizationTracker());

            /*
             * After utilization info is complete and prior to the checkpoint,
             * remove all temporary databases encountered during recovery.
             */
            removeTempDbs();

            /*
             * At this point, we've recovered (or there were no log files at
             * all. Write a checkpoint into the log.
             *
             * NOTE: The discussion of deltas below may be obsolete now that
             * we use dirty bits to determine what to include in a delta.
             * However, we still want to disallow deltas to flush full versions
             * after a crash.
             *
             * Don't allow deltas, because the delta-determining scheme that
             * compares child entries to the last full LSN doesn't work in
             * recovery land. New child entries may have an earlier LSN than
             * the owning BIN's last full, because of the act of splicing in
             * LNs during recovery.
             *
             * For example, suppose that during LN redo, bin 10 was split into
             * bin 10 and bin 12. That splitting causes a full log.  Then later
             * on, the redo splices LN x, which is from before the last full of
             * bin 10, into bin 10. If we checkpoint allowing deltas after
             * recovery finishes, we won't pick up the LNx diff, because that
             * LN is an earlier LSN than the split-induced full log entry of
             * bin 10.
             */
            if (!readOnly &&
                (env.getLogManager().getLastLsnAtRecovery() !=
                 info.checkpointEndLsn ||
                 forceCheckpoint)) {
                CheckpointConfig config = new CheckpointConfig();
                config.setForce(true);
                config.setMinimizeRecoveryTime(true);
                env.invokeCheckpoint(config, false /*flushAll*/, "recovery");
            } else {
                /* Initialze intervals when there is no initial checkpoint. */
                env.getCheckpointer().initIntervals
                    (info.checkpointEndLsn, System.currentTimeMillis());
            }

        } catch (IOException e) {
            Tracer.trace(env, "RecoveryManager", "recover",
                         "Couldn't recover", e);
            throw new RecoveryException(env, "Couldn't recover: " +
                                        e.getMessage(), e);
        } finally {
            Tracer.trace(Level.CONFIG, env, "Recovery finished: " + info);
        }

        return info;
    }

    /**
     * Find the end of the log, initialize the FileManager. While we're
     * perusing the log, return the last checkpoint LSN if we happen to see it.
     */
    private void findEndOfLog(boolean readOnly)
        throws IOException, DatabaseException {

        LastFileReader reader = new LastFileReader(env, readBufferSize);

        /*
         * Tell the reader to iterate through the log file until we hit the end
         * of the log or an invalid entry.  Remember the last seen CkptEnd, and
         * the first CkptStart with no following CkptEnd.
         */
        while (reader.readNextEntry()) {
            LogEntryType type = reader.getEntryType();
            if (LogEntryType.LOG_CKPT_END.equals(type)) {
                info.checkpointEndLsn = reader.getLastLsn();
                info.partialCheckpointStartLsn = DbLsn.NULL_LSN;
            } else if (LogEntryType.LOG_CKPT_START.equals(type)) {
                if (info.partialCheckpointStartLsn == DbLsn.NULL_LSN) {
                    info.partialCheckpointStartLsn = reader.getLastLsn();
                }
            } else if (LogEntryType.LOG_ROOT.equals(type)) {
                info.useRootLsn = reader.getLastLsn();
            }
        }

        /*
         * The last valid LSN should point to the start of the last valid log
         * entry, while the end of the log should point to the first byte of
         * blank space, so these two should not be the same.
         */
        assert (reader.getLastValidLsn() != reader.getEndOfLog()):
            "lastUsed=" + DbLsn.getNoFormatString(reader.getLastValidLsn()) +
            " end=" + DbLsn.getNoFormatString(reader.getEndOfLog());


        /* Now truncate if necessary. */
        if (!readOnly) {
            reader.setEndOfFile();
        }

        /* Tell the fileManager where the end of the log is. */
        info.lastUsedLsn = reader.getLastValidLsn();
        info.nextAvailableLsn = reader.getEndOfLog();
        info.nRepeatIteratorReads += reader.getNRepeatIteratorReads();
        env.getFileManager().setLastPosition(info.nextAvailableLsn,
                                             info.lastUsedLsn,
                                             reader.getPrevOffset());

        /*
         * Now the logging system is initialized and can do more
         * logging. Enable publishing of debug log messages to the database
         * log.
         */
        env.enableDebugLoggingToDbLog();
    }

    /**
     * Find the last checkpoint and establish the firstActiveLsn point,
     * checkpoint start, and checkpoint end.
     */
    private void findLastCheckpoint()
        throws IOException, DatabaseException {

        /*
         * The checkpointLsn might have been already found when establishing
         * the end of the log.  If it was found, then partialCheckpointStartLsn
         * was also found.  If it was not found, search backwards for it now
         * and also set partialCheckpointStartLsn.
         */
        if (info.checkpointEndLsn == DbLsn.NULL_LSN) {

            /*
             * Search backwards though the log for a checkpoint end entry and a
             * root entry.
             */
            CheckpointFileReader searcher =
                new CheckpointFileReader(env, readBufferSize, false,
                                         info.lastUsedLsn, DbLsn.NULL_LSN,
                                         info.nextAvailableLsn);

            while (searcher.readNextEntry()) {

                /*
                 * Continue iterating until we find a checkpoint end entry.
                 * While we're at it, remember the last root seen in case we
                 * don't find a checkpoint end entry.
                 */
                if (searcher.isCheckpointEnd()) {

                    /*
                     * We're done, the checkpoint end will tell us where the
                     * root is.
                     */
                    info.checkpointEndLsn = searcher.getLastLsn();
                    break;
                } else if (searcher.isCheckpointStart()) {

                    /*
                     * Remember the first CkptStart following the CkptEnd.
                     */
                    info.partialCheckpointStartLsn = searcher.getLastLsn();

                } else if (searcher.isRoot()) {

                    /*
                     * Save the last root that was found in the log in case we
                     * don't see a checkpoint.
                     */
                    if (info.useRootLsn == DbLsn.NULL_LSN) {
                        info.useRootLsn = searcher.getLastLsn();
                    }
                }
            }
            info.nRepeatIteratorReads += searcher.getNRepeatIteratorReads();
        }

        /*
         * If we haven't found a checkpoint, we'll have to recover without
         * one. At a minimium, we must have found a root.
         */
        if (info.checkpointEndLsn == DbLsn.NULL_LSN) {
            info.checkpointStartLsn = DbLsn.NULL_LSN;
            info.firstActiveLsn = DbLsn.NULL_LSN;
        } else {
            /* Read in the checkpoint entry. */
            CheckpointEnd checkpointEnd = (CheckpointEnd)
		(env.getLogManager().get(info.checkpointEndLsn));
            info.checkpointEnd = checkpointEnd;
            info.checkpointStartLsn = checkpointEnd.getCheckpointStartLsn();
            info.firstActiveLsn = checkpointEnd.getFirstActiveLsn();

            /*
             * Use the last checkpoint root only if there is no later root.
             * The latest root has the correct per-DB utilization info.
             */
            if (checkpointEnd.getRootLsn() != DbLsn.NULL_LSN &&
                info.useRootLsn == DbLsn.NULL_LSN) {
                info.useRootLsn = checkpointEnd.getRootLsn();
            }

            /* Init the checkpointer's id sequence.*/
            env.getCheckpointer().setCheckpointId(checkpointEnd.getId());
        }
        if (info.useRootLsn == DbLsn.NULL_LSN) {
            throw new NoRootException
                (env,
                 "This environment's log file has no root. Since the root " +
                 "is the first entry written into a log at environment " +
                 "creation, this should only happen if the initial creation " +
                 "of the environment was never checkpointed or synced. " +
                 "Please move aside the existing log files to allow the " +
                 "creation of a new environment");
        }
    }

    /**
     * Use the log to recreate an in memory tree.
     */
    private void buildTree()
        throws IOException, DatabaseException {

        /*
         * Read all map database INs, find largest node id before any
         * possiblity of splits, find largest txn Id before any need for a root
         * update (which would use an AutoTxn)
         */
        int passNum = buildINs(1,
                               true,   /* mapping tree */
                               false); /* dup tree */

        /*
         * Undo all aborted map LNs. Read and remember all committed
         * transaction ids.
         */
        Tracer.trace(Level.CONFIG, env, passStartHeader(passNum) +
                     "undo map LNs");
        long start = System.currentTimeMillis();
        Set<LogEntryType> mapLNSet = new HashSet<LogEntryType>();
        mapLNSet.add(LogEntryType.LOG_MAPLN_TRANSACTIONAL);
        mapLNSet.add(LogEntryType.LOG_TXN_COMMIT);
        mapLNSet.add(LogEntryType.LOG_TXN_ABORT);
        mapLNSet.add(LogEntryType.LOG_TXN_PREPARE);
        undoLNs(info, mapLNSet);
        long end = System.currentTimeMillis();
        Tracer.trace(Level.CONFIG, env, passEndHeader(passNum, start, end) +
                     info.toString());
        passNum++;

        /*
         * Replay all mapLNs, mapping tree in place now. Use the set of
         * committed txns found from the undo pass.
         */
        Tracer.trace(Level.CONFIG, env, passStartHeader(passNum) +
                     "redo map LNs");
        start = System.currentTimeMillis();
        mapLNSet.add(LogEntryType.LOG_MAPLN);
        redoLNs(info, mapLNSet);
        end = System.currentTimeMillis();
        Tracer.trace(Level.CONFIG, env, passEndHeader(passNum, start, end) +
                     info.toString());
        passNum++;

        /*
         * Reconstruct the internal nodes for the main level trees.
         */
        passNum = buildINs(passNum,
                           false,   /* mapping tree*/
                           false);  /* dup tree */

        /*
         * Reconstruct the internal nodes for the duplicate level trees.
         */
        passNum = buildINs(passNum,
                           false,   /* mapping tree*/
                           true);  /* dup tree */

        /*
         * Build the in memory IN list. Before this point, the INList is not
         * enabled, and fetched INs have not been put on the list.  Once the
         * tree is complete we can add the environment to the evictor (for a
         * shared cache) and invoke the evictor.  The evictor will also be
         * invoked during the undo and redo passes.
         */
        buildINList();
        if (env.getSharedCache()) {
            env.getEvictor().addEnvironment(env);
        }
        env.invokeEvictor();

        /*
         * Undo aborted LNs. No need to collect committed txn ids again, was
         * done in the undo of all aborted MapLNs.
         */
        Tracer.trace(Level.CONFIG, env, passStartHeader(9) + "undo LNs");
        start = System.currentTimeMillis();
        Set<LogEntryType> lnSet = new HashSet<LogEntryType>();
        lnSet.add(LogEntryType.LOG_LN_TRANSACTIONAL);
        lnSet.add(LogEntryType.LOG_NAMELN_TRANSACTIONAL);
        lnSet.add(LogEntryType.LOG_DEL_DUPLN_TRANSACTIONAL);
        lnSet.add(LogEntryType.LOG_DUPCOUNTLN_TRANSACTIONAL);

        undoLNs(info, lnSet);
        end = System.currentTimeMillis();
        Tracer.trace(Level.CONFIG, env, passEndHeader(9, start, end) +
                     info.toString());

        /* Replay LNs. Also read non-transactional LNs. */
        Tracer.trace(Level.CONFIG, env, passStartHeader(10) + "redo LNs");
        start = System.currentTimeMillis();
        lnSet.add(LogEntryType.LOG_LN);
        lnSet.add(LogEntryType.LOG_NAMELN);
        lnSet.add(LogEntryType.LOG_DEL_DUPLN);
        lnSet.add(LogEntryType.LOG_DUPCOUNTLN);
        lnSet.add(LogEntryType.LOG_FILESUMMARYLN);
        redoLNs(info, lnSet);
        end = System.currentTimeMillis();
        Tracer.trace(Level.CONFIG, env, passEndHeader(10, start, end) +
                     info.toString());
    }

    /*
     * Up to three passes for the INs of a given level
     * @param mappingTree if true, we're building the mapping tree
     * @param dupTree if true, we're building the dup tree.
     */
    private int buildINs(int passNum,
                         boolean mappingTree,
                         boolean dupTree)
        throws IOException, DatabaseException {

        Set<LogEntryType> targetEntries = new HashSet<LogEntryType>();
        Set<LogEntryType> deltaType = new HashSet<LogEntryType>();
        String passADesc = null;
        String passBDesc = null;
        String passCDesc = null;

        if (mappingTree) {
            passADesc = "read mapping INs";
            passBDesc = "redo mapping INs";
            passCDesc = "read mapping BINDeltas";
        } else if (dupTree) {
            passADesc = "read dup INs";
            passBDesc = "redo dup INs";
            passCDesc = "read dup BINDeltas";
        } else {
            passADesc = "read main INs";
            passBDesc = "redo main INs";
            passCDesc = "read main BINDeltas";
        }

        if (dupTree) {
            /* Duplicate trees read these entries. */
            targetEntries.add(LogEntryType.LOG_DIN);
            targetEntries.add(LogEntryType.LOG_DBIN);
            targetEntries.add(LogEntryType.LOG_IN_DUPDELETE_INFO);
            deltaType.add(LogEntryType.LOG_DUP_BIN_DELTA);
        } else {
            /* Main tree and mapping tree read these types of entries. */
            targetEntries.add(LogEntryType.LOG_IN);
            targetEntries.add(LogEntryType.LOG_BIN);
            targetEntries.add(LogEntryType.LOG_IN_DELETE_INFO);
            deltaType.add(LogEntryType.LOG_BIN_DELTA);
        }

        /*
         * Pass a: Read all INs and place into the proper location.
         */
        Tracer.trace(Level.CONFIG, env, passStartHeader(passNum) + passADesc);
        LevelRecorder recorder = new LevelRecorder();
        long start = System.currentTimeMillis();
        if (mappingTree) {
            readINsAndTrackIds(info.checkpointStartLsn, recorder);
        } else {
            int numINsSeen = readINs(info.checkpointStartLsn,
                                     false,  // mapping tree only
                                     targetEntries,

                                     /*
                                      * requireExactMatch -- why is it true for
                                      * dups, false for main tree?  Keeping
                                      * logic the same for now.
                                      */
                                     (dupTree? true: false),
                                     recorder);
            if (dupTree) {
                info.numDuplicateINs += numINsSeen;
            } else {
                info.numOtherINs += numINsSeen;
            }
        }
        long end = System.currentTimeMillis();
        Tracer.trace(Level.CONFIG, env, passEndHeader(passNum, start, end) +
                     info.toString());
        passNum++;

        /*
         * Pass b: Redo INs if the LevelRecorder detects a split/compression
         * was done after ckpt [#14424]
         */
        Set<DatabaseId> redoSet = recorder.getDbsWithDifferentLevels();
        if (redoSet.size() > 0) {
            Tracer.trace(Level.CONFIG, env,
                         passStartHeader(passNum) + passBDesc);
            start = System.currentTimeMillis();
            repeatReadINs(info.checkpointStartLsn,
                          targetEntries,
                          redoSet);
            end = System.currentTimeMillis();
            Tracer.trace(Level.CONFIG, env,
                         passEndHeader(passNum, start, end) + info.toString());
            passNum++;
        }

        /*
         * Pass c: Read BIN Deltas.
         * BINDeltas must be processed after all INs so the delta is properly
         * applied to the last version. For example, suppose BINDeltas were not
         * done in a later pass, the tree is INa->BINb, and the log has
         *       INa
         *       BINDelta for BINb
         *       INa
         * the splicing in of the second INa would override the BINDelta.
         */
        Tracer.trace(Level.CONFIG, env, passStartHeader(passNum) + passCDesc);
        start = System.currentTimeMillis();
        info.numBinDeltas += readINs(info.checkpointStartLsn,
                                     mappingTree,
                                     deltaType,
                                     true,   // requireExactMatch
                                     null);  // LevelRecorder
        end = System.currentTimeMillis();
        Tracer.trace(Level.CONFIG, env,
                     passEndHeader(passNum, start, end) + info.toString());
        passNum++;

        return passNum;
    }

    /*
     * Read every internal node and IN DeleteInfo in the mapping tree and place
     * in the in-memory tree. Also peruse all pertinent log entries in order to
     * update our knowledge of the last used database, transaction and node
     * ids, and to to track utilization profile and vlsn->lsn mappings.
     */
    private void readINsAndTrackIds(long rollForwardLsn,
                                    LevelRecorder recorder)
        throws IOException, DatabaseException {

        INFileReader reader =
            new INFileReader(env,
                             readBufferSize,
                             rollForwardLsn,        // start lsn
                             info.nextAvailableLsn, // end lsn
                             true,   // track node and db ids
                             false,  // map db only
                             info.partialCheckpointStartLsn,
                             info.checkpointEndLsn,
                             tracker);
        reader.addTargetType(LogEntryType.LOG_IN);
        reader.addTargetType(LogEntryType.LOG_BIN);
        reader.addTargetType(LogEntryType.LOG_IN_DELETE_INFO);

        /* Validate all entries in at least one full recovery pass. */
        reader.setAlwaysValidateChecksum(true);

        try {
            info.numMapINs = 0;
            DbTree dbMapTree = env.getDbTree();

            /* Process every IN, BIN and INDeleteInfo in the mapping tree. */
            while (reader.readNextEntry()) {
                DatabaseId dbId = reader.getDatabaseId();
                if (dbId.equals(DbTree.ID_DB_ID)) {
                    DatabaseImpl db = dbMapTree.getDb(dbId);
                    try {
                        replayOneIN(reader, db, false, recorder);
                        info.numMapINs++;
                    } finally {
                        dbMapTree.releaseDb(db);
                    }
                }
            }

            /*
             * Update node id, database id, and txn id sequences. Use either
             * the maximum of the ids seen by the reader vs. the ids stored in
             * the checkpoint.
             */
            info.useMinReplicatedNodeId = reader.getMinReplicatedNodeId();
            info.useMaxNodeId = reader.getMaxNodeId();

            info.useMinReplicatedDbId = reader.getMinReplicatedDbId();
            info.useMaxDbId = reader.getMaxDbId();

            info.useMinReplicatedTxnId = reader.getMinReplicatedTxnId();
            info.useMaxTxnId = reader.getMaxTxnId();

            if (info.checkpointEnd != null) {
                CheckpointEnd ckptEnd = info.checkpointEnd;

                if (info.useMinReplicatedNodeId >
                    ckptEnd.getLastReplicatedNodeId()) {
                    info.useMinReplicatedNodeId =
                        ckptEnd.getLastReplicatedNodeId();
                }
                if (info.useMaxNodeId < ckptEnd.getLastLocalNodeId()) {
                    info.useMaxNodeId = ckptEnd.getLastLocalNodeId();
                }

                if (info.useMinReplicatedDbId >
                    ckptEnd.getLastReplicatedDbId()) {
                    info.useMinReplicatedDbId =
                        ckptEnd.getLastReplicatedDbId();
                }
                if (info.useMaxDbId < ckptEnd.getLastLocalDbId()) {
                    info.useMaxDbId = ckptEnd.getLastLocalDbId();
                }

                if (info.useMinReplicatedTxnId >
                    ckptEnd.getLastReplicatedTxnId()) {
                    info.useMinReplicatedTxnId =
                        ckptEnd.getLastReplicatedTxnId();
                }
                if (info.useMaxTxnId < ckptEnd.getLastLocalTxnId()) {
                    info.useMaxTxnId = ckptEnd.getLastLocalTxnId();
                }
            }

            env.getNodeSequence().
                setLastNodeId(info.useMinReplicatedNodeId, info.useMaxNodeId);
            env.getDbTree().setLastDbId(info.useMinReplicatedDbId,
                                        info.useMaxDbId);
            env.getTxnManager().setLastTxnId(info.useMinReplicatedTxnId,
                                             info.useMaxTxnId);

            info.nRepeatIteratorReads += reader.getNRepeatIteratorReads();

            info.fileMappers = reader.getFileMappers();
        } catch (Exception e) {
            traceAndThrowException(reader.getLastLsn(), "readMapIns", e);
        }
    }

    /**
     * Read INs and process.
     */
    private int readINs(long rollForwardLsn,
                        boolean mapDbOnly,
                        Set<LogEntryType> targetLogEntryTypes,
                        boolean requireExactMatch,
                        LevelRecorder recorder)
        throws IOException, DatabaseException {

        /* Don't need to track NodeIds. */
        INFileReader reader =
            new INFileReader(env,
                             readBufferSize,
                             rollForwardLsn,                 // startlsn
                             info.nextAvailableLsn,          // finish
                             false,
                             mapDbOnly,
                             info.partialCheckpointStartLsn,
                             info.checkpointEndLsn,
                             tracker);

        Iterator<LogEntryType> iter = targetLogEntryTypes.iterator();
        while (iter.hasNext()) {
            reader.addTargetType(iter.next());
        }

        int numINsSeen = 0;
        try {

            /*
             * Read all non-provisional INs, and process if they don't belong
             * to the mapping tree.
             */
            DbTree dbMapTree = env.getDbTree();
            while (reader.readNextEntry()) {
                DatabaseId dbId = reader.getDatabaseId();
                boolean isMapDb = dbId.equals(DbTree.ID_DB_ID);
                boolean isTarget = false;

                if (mapDbOnly && isMapDb) {
                    isTarget = true;
                } else if (!mapDbOnly && !isMapDb) {
                    isTarget = true;
                }
                if (isTarget) {
                    DatabaseImpl db = dbMapTree.getDb(dbId);
                    try {
                        if (db == null) {
                            // This db has been deleted, ignore the entry.
                        } else {
                            replayOneIN(reader, db, requireExactMatch,
                                        recorder);
                            numINsSeen++;

                            /*
                             * Add any db that we encounter IN's for because
                             * they'll be part of the in-memory tree and
                             * therefore should be included in the INList
                             * build.
                             */
                            inListBuildDbIds.add(dbId);
                        }
                    } finally {
                        dbMapTree.releaseDb(db);
                    }
                }
            }

            info.nRepeatIteratorReads += reader.getNRepeatIteratorReads();
            return numINsSeen;
        } catch (Exception e) {
            traceAndThrowException(reader.getLastLsn(), "readNonMapIns", e);
            return 0;
        }
    }

    /**
     * Read INs and process.
     */
    private void repeatReadINs(long rollForwardLsn,
                               Set<LogEntryType> targetLogEntryTypes,
                               Set<DatabaseId> targetDbs)
        throws IOException, DatabaseException {

        // don't need to track NodeIds
        INFileReader reader =
            new INFileReader(env,
                             readBufferSize,
                             rollForwardLsn,                 // startlsn
                             info.nextAvailableLsn,          // finish
                             false,
                             false,                          // mapDbOnly
                             info.partialCheckpointStartLsn,
                             info.checkpointEndLsn,
                             tracker);

        Iterator<LogEntryType> iter = targetLogEntryTypes.iterator();
        while (iter.hasNext()) {
            reader.addTargetType(iter.next());
        }

        try {

            /* Read all non-provisional INs that are in the repeat set. */
            DbTree dbMapTree = env.getDbTree();
            while (reader.readNextEntry()) {
                DatabaseId dbId = reader.getDatabaseId();
                if (targetDbs.contains(dbId)) {
                    DatabaseImpl db = dbMapTree.getDb(dbId);
                    try {
                        if (db == null) {
                            // This db has been deleted, ignore the entry.
                        } else {
                            replayOneIN(reader,
                                        db,
                                        true,  // requireExactMatch,
                                        null); // level recorder
                        }
                    } finally {
                        dbMapTree.releaseDb(db);
                    }
                }
            }

            info.nRepeatIteratorReads += reader.getNRepeatIteratorReads();
        } catch (Exception e) {
            traceAndThrowException(reader.getLastLsn(), "readNonMapIns", e);
        }
    }

    /**
     * Get an IN from the reader, set its database, and fit into tree.
     */
    private void replayOneIN(INFileReader reader,
                             DatabaseImpl db,
                             boolean requireExactMatch,
                             LevelRecorder recorder)
        throws DatabaseException {

        if (reader.isDeleteInfo()) {
            /* Last entry is a delete, replay it. */
            replayINDelete(db,
                           reader.getDeletedNodeId(),
                           false,
                           reader.getDeletedIdKey(),
                           null,
                           reader.getLastLsn());
        } else if (reader.isDupDeleteInfo()) {
            /* Last entry is a dup delete, replay it. */
            replayINDelete(db,
                           reader.getDupDeletedNodeId(),
                           true,
                           reader.getDupDeletedMainKey(),
                           reader.getDupDeletedDupKey(),
                           reader.getLastLsn());
        } else {

            /*
             * Last entry is a node, replay it. Now, we should really call
             * IN.postFetchInit, but we want to do something different from the
             * faulting-in-a-node path, because we don't want to put the IN on
             * the in memory list, and we don't want to search the db map tree,
             * so we have a IN.postRecoveryInit.  Note also that we have to
             * pass the LSN of the current log entry and also the LSN of the IN
             * in question. The only time these differ is when the log entry is
             * a BINDelta -- then the IN's LSN is the last full version LSN,
             * and the log LSN is the current log entry.
             */
            IN in = reader.getIN();
            long inLsn = reader.getLsnOfIN();
            in.postRecoveryInit(db, inLsn);
            in.latch();

            /*
             * Track the levels, in case we need an extra splits vs ckpt
             * reconcilliation.
             */
            if (recorder != null) {
                recorder.record(db.getId(), in.getLevel());
            }
            replaceOrInsert(db, in, reader.getLastLsn(), inLsn,
                            requireExactMatch);
        }
    }

    /**
     * Undo all aborted LNs. To do so, walk the log backwards, keeping a
     * collection of committed txns. If we see a log entry that doesn't have a
     * committed txn, undo it.
     */
    private void undoLNs(RecoveryInfo info, Set<LogEntryType> lnTypes)
        throws IOException, DatabaseException {

        long firstActiveLsn = info.firstActiveLsn;
        long lastUsedLsn = info.lastUsedLsn;
        long endOfFileLsn = info.nextAvailableLsn;
        /* Set up a reader to pick up target log entries from the log. */
        LNFileReader reader =
            new LNFileReader(env, readBufferSize, lastUsedLsn,
                             false, endOfFileLsn, firstActiveLsn, null,
                             info.checkpointEndLsn);

        Iterator<LogEntryType> iter = lnTypes.iterator();
        while (iter.hasNext()) {
            LogEntryType lnType = iter.next();
            reader.addTargetType(lnType);
        }

        Map<TxnNodeId,Long> countedFileSummaries = 
            new HashMap<TxnNodeId,Long>(); // TxnNodeId -> file number
        Set<TxnNodeId> countedAbortLsnNodes = new HashSet<TxnNodeId>();

        DbTree dbMapTree = env.getDbTree();
        TreeLocation location = new TreeLocation();
        try {

            /*
             * Iterate over the target LNs and commit records, constructing
             * tree.
             */
            while (reader.readNextEntry()) {
                if (reader.isLN()) {

                    /* Get the txnId from the log entry. */
                    Long txnId = reader.getTxnId();

                    /*
                     * If this node is not in a committed or prepared txn,
                     * examine it to see if it should be undone.
                     */
                    if (txnId != null &&
			!committedTxnIds.containsKey(txnId) &&
			preparedTxns.get(txnId) == null) {

			/*
			 * Invoke the evictor to reduce memory consumption.
			 */
			env.invokeEvictor();

			LN ln = reader.getLN();
			long logLsn = reader.getLastLsn();
			long abortLsn = reader.getAbortLsn();
			boolean abortKnownDeleted =
			    reader.getAbortKnownDeleted();
			DatabaseId dbId = reader.getDatabaseId();
			DatabaseImpl db = dbMapTree.getDb(dbId);
                        try {
                            /* Database may be null if it's been deleted. */
                            if (db != null) {
                                ln.postFetchInit(db, logLsn);
				undo(detailedTraceLevel, db, location, ln,
				     reader.getKey(), reader.getDupTreeKey(),
				     logLsn, abortLsn, abortKnownDeleted,
				     info, true);

                                /* Undo utilization info. */
                                TxnNodeId txnNodeId =
                                    new TxnNodeId(reader.getNodeId(),
                                                  txnId.longValue());
                                undoUtilizationInfo(ln, db, logLsn, abortLsn,
                                                    abortKnownDeleted,
                                                    reader.getLastEntrySize(),
                                                    txnNodeId,
                                                    countedFileSummaries,
                                                    countedAbortLsnNodes);

                                /*
                                 * Add any db that we encounter LN's for
                                 * because they'll be part of the in-memory
                                 * tree and therefore should be included in the
                                 * INList build.
                                 */
                                inListBuildDbIds.add(dbId);

                                /*
                                 * For temporary DBs that are encountered as
                                 * MapLNs, add them to the set of databases to
                                 * be removed.
                                 */
                                MapLN mapLN = reader.getMapLN();
                                if (mapLN != null &&
                                    mapLN.getDatabase().isTemporary()) {
                                    tempDbIds.add(mapLN.getDatabase().getId());
                                }
                            }
                        } finally {
                            dbMapTree.releaseDb(db);
                        }
		    }
                } else if (reader.isPrepare()) {

                    /*
                     * The entry just read is a prepare record.  There should
                     * be no lock conflicts during recovery, but just in case
                     * there are, we set the locktimeout to 0.
                     */
                    long prepareId = reader.getTxnPrepareId();
                    Long prepareIdL = Long.valueOf(prepareId);
                    if (!committedTxnIds.containsKey(prepareIdL) &&
                        !abortedTxnIds.contains(prepareIdL)) {
                        TransactionConfig txnConf = new TransactionConfig();
                        Txn preparedTxn = PreparedTxn.createPreparedTxn
			    (env, txnConf, prepareId);
                        preparedTxn.setLockTimeout(0);
                        preparedTxns.put(prepareIdL, preparedTxn);
			preparedTxn.setPrepared(true);
                        env.getTxnManager().registerXATxn
                            (reader.getTxnPrepareXid(), preparedTxn, true);
                        Tracer.trace(Level.INFO, env,
                                     "Found unfinished prepare record: id: " +
                                     reader.getTxnPrepareId() +
                                     " Xid: " + reader.getTxnPrepareXid());
                    }
                } else if (reader.isAbort()) {
                    /* The entry just read is an abort record. */
                    abortedTxnIds.add(Long.valueOf(reader.getTxnAbortId()));
                } else {
                    /* The entry just read is a commit record. */
                    committedTxnIds.put(Long.valueOf(reader.getTxnCommitId()),
                                        Long.valueOf(reader.getLastLsn()));
                }
            }
            info.nRepeatIteratorReads += reader.getNRepeatIteratorReads();
        } catch (RuntimeException e) {
            traceAndThrowException(reader.getLastLsn(), "undoLNs", e);
        }
    }

    /**
     * Apply all committed LNs.
     * @param rollForwardLsn start redoing from this point
     * @param lnType1 targetted LN
     * @param lnType2 targetted LN
     */
    private void redoLNs(RecoveryInfo info, Set<LogEntryType> lnTypes)
        throws IOException, DatabaseException {

        long endOfFileLsn = info.nextAvailableLsn;
        long rollForwardLsn = info.checkpointStartLsn;
	long firstActiveLsn = info.firstActiveLsn;

        /* 
	 * Set up a reader to pick up target log entries from the log.  For
	 * most LNs, we should only redo LNs starting at the checkpoint start
	 * LSN.  However, LNs that are prepared, but not committed, (i.e. those
	 * LNs that belong to 2PC txns that have been prepared, but still not
	 * committed), still need to be processed and they can live in the log
	 * between the firstActive LSN and the checkpointStart LSN.  So we
	 * start the LNFileReader at the First Active LSN.
	 */
        LNFileReader reader =
            new LNFileReader(env, readBufferSize, firstActiveLsn,
                             true, DbLsn.NULL_LSN, endOfFileLsn, null,
                             info.checkpointEndLsn);

        Iterator<LogEntryType> iter = lnTypes.iterator();
        while (iter.hasNext()) {
            LogEntryType lnType = iter.next();
            reader.addTargetType(lnType);
        }

        Set<TxnNodeId> countedAbortLsnNodes = new HashSet<TxnNodeId>();

        DbTree dbMapTree = env.getDbTree();
        TreeLocation location = new TreeLocation();
        try {

            /*
             * Iterate over the target LNs and construct in- memory tree.
             */
            while (reader.readNextEntry()) {
                long lastLsn = reader.getLastLsn();

                /*
                 * preparedOnlyLNs indicates that we're processing LSNs between
                 * the First Active LSN and the Checkpoint Start LSN.  In this
                 * range, only LNs which are prepared, but not committed,
                 * should be processed. If there is no checkpoint, the
                 * beginning of the log is really the First Active LSN, and all
                 * prepared LNs should be processed.
                 */
                boolean preparedOnlyLNs =
                    (rollForwardLsn == DbLsn.NULL_LSN) ? 
                    true : 
                    (DbLsn.compareTo(lastLsn, rollForwardLsn) < 0);

                if (reader.isLN()) {

                    /* Get the txnId from the log entry. */
                    Long txnId = reader.getTxnId();

                    /*
                     * If this LN is in a committed txn, or if it's a
                     * non-transactional LN between the checkpoint start and
                     * the end of the log, then redo it.  If it's a prepared LN
                     * in the log between the first active LSN and the end of
                     * the log, resurrect it.
                     */
                    boolean processThisLN = false;
                    boolean lnIsCommitted = false;
                    boolean lnIsPrepared = false;
                    long commitLsn = DbLsn.NULL_LSN;
                    Txn preparedTxn = null;
                    if (txnId == null &&
                        !preparedOnlyLNs) {
                        processThisLN = true;
                    } else {
                        lnIsCommitted = committedTxnIds.containsKey(txnId);
                        if (lnIsCommitted) {
                            commitLsn = committedTxnIds.get(txnId).
                                longValue();
                        } else {
                            preparedTxn = preparedTxns.get(txnId);
                            lnIsPrepared = preparedTxn != null;
                        }
                        if ((lnIsCommitted && !preparedOnlyLNs) ||
                            lnIsPrepared) {
                            processThisLN = true;
                        }
                    }
                    if (processThisLN) {

                        /* Invoke the evictor to reduce memory consumption. */
                        env.invokeEvictor();

                        LN ln = reader.getLN();
                        DatabaseId dbId = reader.getDatabaseId();
                        DatabaseImpl db = dbMapTree.getDb(dbId);
                        try {
                            long logLsn = reader.getLastLsn();
                            long treeLsn = DbLsn.NULL_LSN;

                            /* Database may be null if it's been deleted. */
                            if (db != null) {
                                ln.postFetchInit(db, logLsn);

                                if (preparedTxn != null) {
                                    preparedTxn.addLogInfo(logLsn);

                                    /*
                                     * We're reconstructing a prepared, but not
                                     * finished, transaction.  We know that
                                     * there was a write lock on this LN since
                                     * it exists in the log under this txnId.
                                     */
                                    LockResult lockResult = preparedTxn.lock
                                        (ln.getNodeId(), LockType.WRITE,
                                         false /*noWait*/, db);
                                    lockResult.setAbortLsn
                                        (reader.getAbortLsn(),
                                         reader.getAbortKnownDeleted()); 
                                }

                                treeLsn = redo(db,
                                               location,
                                               ln,
                                               reader.getKey(),
                                               reader.getDupTreeKey(),
                                               logLsn,
                                               info);

                                /*
                                 * Add any db that we encounter LN's for
                                 * because they'll be part of the in-memory
                                 * tree and therefore should be included in the
                                 * INList build.
                                 */
                                inListBuildDbIds.add(dbId);

                                /*
                                 * For temporary DBs that are encountered as
                                 * MapLNs, add them to the set of databases to
                                 * be removed.
                                 */
                                MapLN mapLN = reader.getMapLN();
                                if (mapLN != null &&
                                    mapLN.getDatabase().isTemporary()) {
                                    tempDbIds.add(mapLN.getDatabase().getId());
                                }

                                /*
                                 * For deleted MapLNs (truncated or removed
                                 * DBs), redo utilization counting by counting
                                 * the entire database as obsolete.
                                 */
                                if (mapLN != null && mapLN.isDeleted()) {
                                    mapLN.getDatabase().countObsoleteDb
                                        (tracker, logLsn);
                                }

                                /* Redo utilization info. */
                                TxnNodeId txnNodeId = null;
                                if (txnId != null) {
                                    txnNodeId = new TxnNodeId
                                        (reader.getNodeId(),
                                         txnId.longValue());
                                }
                                redoUtilizationInfo
                                    (logLsn, treeLsn, commitLsn,
                                     reader.getAbortLsn(),
                                     reader.getAbortKnownDeleted(),
                                     reader.getLastEntrySize(),
                                     reader.getKey(),
                                     ln, db, txnNodeId, countedAbortLsnNodes);
                            }
                        } finally {
                            dbMapTree.releaseDb(db);
                        }
                    }
                }
            }
            info.nRepeatIteratorReads += reader.getNRepeatIteratorReads();
        } catch (Exception e) {
            traceAndThrowException(reader.getLastLsn(), "redoLns", e);
        }
    }

    /**
     * Build the in memory inList with INs that have been made resident by the
     * recovery process.
     */
    private void buildINList()
        throws DatabaseException {

        env.getInMemoryINs().enable();           // enable INList
        env.getDbTree().rebuildINListMapDb();    // scan map db

        /* For all the dbs that we read in recovery, scan for resident INs. */
        Iterator<DatabaseId> iter = inListBuildDbIds.iterator();
        while (iter.hasNext()) {
            DatabaseId dbId = iter.next();
            /* We already did the map tree, don't do it again. */
            if (!dbId.equals(DbTree.ID_DB_ID)) {
                DatabaseImpl db = env.getDbTree().getDb(dbId);
                try {
                    if (db != null) {
                        /* Temp DBs will be removed, skip build. */
                        if (!db.isTemporary()) {
                            db.getTree().rebuildINList();
                        }
                    }
                } finally {
                    env.getDbTree().releaseDb(db);
                }
            }
        }
    }

    /* Struct to hold a nodeId/txnId tuple */
    private static class TxnNodeId {
        long nodeId;
        long txnId;

        TxnNodeId(long nodeId, long txnId) {
            this.nodeId = nodeId;
            this.txnId = txnId;
        }

        /**
         * Compare two TxnNodeId objects
         */
        @Override
        public boolean equals(Object obj) {
            if (this == obj) {
                return true;
            }

            if (!(obj instanceof TxnNodeId)) {
                return false;
            }

            return ((((TxnNodeId) obj).txnId == txnId) &&
                    (((TxnNodeId) obj).nodeId == nodeId));
        }

        @Override
        public int hashCode() {
            return (int) (txnId + nodeId);
        }

        public String toString() {
            return "txnId=" + txnId + "/nodeId=" + nodeId;
        }
    }

    /*
     * Tree manipulation methods.
     */

    /**
     * Recover an internal node. If inFromLog is:
     *       - not found, insert it in the appropriate location.
     *       - if found and there is a physical match (LSNs are the same)
     *         do nothing.
     *       - if found and there is a logical match (LSNs are different,
     *         another version of this IN is in place, replace the found node
     *         with the node read from the log only if the log version's
     *         LSN is greater.
     * InFromLog should be latched upon entering this method and it will
     * not be latched upon exiting.
     *
     * @param inFromLog - the new node to put in the tree.  The identifier key
     * and node id are used to find the existing version of the node.
     * @param logLsn - the location of log entry in in the log.
     * @param inLsn LSN of this in -- may not be the same as the log LSN if
     * the current entry is a BINDelta
     * @param requireExactMatch - true if we won't place this node in the tree
     * unless we find exactly that parent. Used for BINDeltas, where we want
     * to only apply the BINDelta to that exact node.
     */
    private void replaceOrInsert(DatabaseImpl db,
                                 IN inFromLog,
                                 long logLsn,
                                 long inLsn,
                                 boolean requireExactMatch)
        throws DatabaseException {

        List<TrackingInfo> trackingList = null;
        boolean inFromLogLatchReleased = false;
        try {

            /*
             * We must know a priori if this node is the root. We can't infer
             * that status from a search of the existing tree, because
             * splitting the root is done by putting a node above the old root.
             * A search downward would incorrectly place the new root below the
             * existing tree.
             */
            if (inFromLog.isRoot()) {
                if (inFromLog.containsDuplicates()) {
                    replaceOrInsertDuplicateRoot(db, (DIN) inFromLog, logLsn);
                } else {
                    replaceOrInsertRoot(db, inFromLog, logLsn);
		    inFromLogLatchReleased = true;
                }
            } else {

                /*
                 * Look for a parent. The call to getParentNode unlatches node.
                 * Then place inFromLog in the tree if appropriate.
                 */
                trackingList = new ArrayList<TrackingInfo>();
                replaceOrInsertChild(db, inFromLog, logLsn, inLsn,
                                     trackingList, requireExactMatch);
		inFromLogLatchReleased = true;
            }
        } catch (Exception e) {
            String trace = printTrackList(trackingList);
            Tracer.trace(db.getDbEnvironment(), "RecoveryManager",
                         "replaceOrInsert", " lsnFromLog:" +
                         DbLsn.getNoFormatString(logLsn) + " " + trace,
                         e);
            throw new DatabaseException
		("lsnFromLog=" + DbLsn.getNoFormatString(logLsn), e);
        } finally {
	    if (!inFromLogLatchReleased) {
		inFromLog.releaseLatch();
	    }

            assert (LatchSupport.countLatchesHeld() == 0):
                LatchSupport.latchesHeldToString() +
                "LSN = " + DbLsn.toString(logLsn) +
                " inFromLog = " + inFromLog.getNodeId();
        }
    }

    /**
     * Dump a tracking list into a string.
     */
    private String printTrackList(List<TrackingInfo> trackingList) {
        if (trackingList != null) {
            StringBuffer sb = new StringBuffer();
            Iterator<TrackingInfo> iter = trackingList.iterator();
            sb.append("Trace list:");
            sb.append('\n');
            while (iter.hasNext()) {
                sb.append(iter.next());
                sb.append('\n');
            }
            return sb.toString();
        } else {
            return null;
        }
    }

    /**
     * Replay an IN delete. Remove an entry from an IN to reflect a reverse
     * split.
     */
    private void replayINDelete(DatabaseImpl db,
                                long nodeId,
                                boolean containsDuplicates,
                                byte[] mainKey,
                                byte[] dupKey,
                                long logLsn)
        throws DatabaseException {

        boolean found = false;
        boolean deleted = false;
        Tree tree = db.getTree();
        SearchResult result = new SearchResult();

        try {
            /* Search for the parent of this target node. */
            result = db.getTree().getParentINForChildIN
                (nodeId,
                 containsDuplicates,
                 false, // do not stop at dup tree root
                 mainKey,
                 dupKey,
                 false, // requireExactMatch
                 CacheMode.UNCHANGED,
                 -1,    // targetLevel
                 null,  // trackingList
                 true); // doFetch

            if (result.parent == null) {
                /* It's null -- we actually deleted the root. */
                tree.withRootLatchedExclusive(new RootDeleter(tree));

                /*
                 * Dirty the database to call DbTree.modifyDbRoot later during
                 * the checkpoint.  We should not log a DatabaseImpl until its
                 * utilization info is correct.
                 */
                db.setDirtyUtilization();
                traceRootDeletion(Level.FINE, db);
                deleted = true;
            } else if (result.exactParentFound) {
                /* Exact match was found -- delete the parent entry. */
                found = true;
                deleted = result.parent.deleteEntry(result.index, false);
            }
        } finally {
            if (result.parent != null) {
                result.parent.releaseLatch();
            }

            traceINDeleteReplay
                (nodeId, logLsn, found, deleted, result.index,
                 containsDuplicates);
        }
    }

    /*
     * RootDeleter lets us clear the rootIN within the root latch.
     */
    private static class RootDeleter implements WithRootLatched {
        Tree tree;
        RootDeleter(Tree tree) {
            this.tree = tree;
        }

        /**
         * @return true if the in-memory root was replaced.
         */
        public IN doWork(ChildReference root)
            throws DatabaseException {

            tree.setRoot(null, false);
            return null;
        }
    }

    /**
     * If the root of this tree is null, use this IN from the log as a root.
     * Note that we should really also check the LSN of the mapLN, because
     * perhaps the root is null because it's been deleted. However, the replay
     * of all the LNs will end up adjusting the tree correctly.
     *
     * If there is a root, check if this IN is a different LSN and if so,
     * replace it.
     */
    private void replaceOrInsertRoot(DatabaseImpl db, IN inFromLog, long lsn)
        throws DatabaseException {

        boolean success = true;
        Tree tree = db.getTree();
        RootUpdater rootUpdater = new RootUpdater(tree, inFromLog, lsn);
        try {
            /* Run the root updater while the root latch is held. */
            tree.withRootLatchedExclusive(rootUpdater);

            /* Update the mapLN if necessary */
            if (rootUpdater.updateDone()) {

                /*
                 * Dirty the database to call DbTree.modifyDbRoot later during
                 * the checkpoint.  We should not log a DatabaseImpl until its
                 * utilization info is correct.
                 */
                db.setDirtyUtilization();
            }
        } catch (Exception e) {
            success = false;
            throw new DatabaseException("lsnFromLog=" +
                                        DbLsn.getNoFormatString(lsn),
                                        e);
        } finally {
	    if (rootUpdater.getInFromLogIsLatched()) {
		inFromLog.releaseLatch();
	    }

            trace(detailedTraceLevel,
                  db, TRACE_ROOT_REPLACE, success, inFromLog,
                  lsn,
                  null,
                  true,
                  rootUpdater.getReplaced(),
                  rootUpdater.getInserted(),
                  rootUpdater.getOriginalLsn(),
                  DbLsn.NULL_LSN,
                  -1);
        }
    }

    /*
     * RootUpdater lets us replace the tree root within the tree root latch.
     */
    private static class RootUpdater implements WithRootLatched {
        private Tree tree;
        private IN inFromLog;
        private long lsn = DbLsn.NULL_LSN;
        private boolean inserted = false;
        private boolean replaced = false;
        private long originalLsn = DbLsn.NULL_LSN;
	private boolean inFromLogIsLatched = true;

        RootUpdater(Tree tree, IN inFromLog, long lsn) {
            this.tree = tree;
            this.inFromLog = inFromLog;
            this.lsn = lsn;
        }

	boolean getInFromLogIsLatched() {
	    return inFromLogIsLatched;
	}

        public IN doWork(ChildReference root)
            throws DatabaseException {

            ChildReference newRoot =
                tree.makeRootChildReference(inFromLog, new byte[0], lsn);
            inFromLog.releaseLatch();
	    inFromLogIsLatched = false;

            if (root == null) {
                tree.setRoot(newRoot, false);
                inserted = true;
            } else {
                originalLsn = root.getLsn(); // for debugLog

                /*
                 * The current in-memory root IN is older than the root IN from
                 * the log.
                 */
                if (DbLsn.compareTo(originalLsn, lsn) < 0) {
                    tree.setRoot(newRoot, false);
                    replaced = true;
                }
            }
            return null;
        }

        boolean updateDone() {
            return inserted || replaced;
        }

        boolean getInserted() {
            return inserted;
        }

        boolean getReplaced() {
            return replaced;
        }

        long getOriginalLsn() {
            return originalLsn;
        }
    }

    /**
     * Recover this root of a duplicate tree.
     */
    private void replaceOrInsertDuplicateRoot(DatabaseImpl db,
                                              DIN inFromLog,
                                              long lsn)
        throws DatabaseException {

        boolean found = true;
        boolean inserted = false;
        boolean replaced = false;
        long originalLsn = DbLsn.NULL_LSN;

        byte[] mainTreeKey = inFromLog.getMainTreeKey();
        IN parent = null;
        int index = -1;
        boolean success = false;
        try {

            /*
             * Allow splits since the parent BIN of this DIN may be full.
             * [#13435]
             */
            parent = db.getTree().searchSplitsAllowed
                (mainTreeKey, -1, CacheMode.DEFAULT);
            assert parent instanceof BIN;

            ChildReference newRef =
                new ChildReference(inFromLog, mainTreeKey, lsn);
            index = parent.insertEntry1(newRef);
            if ((index >= 0 &&
                 (index & IN.EXACT_MATCH) != 0)) {

                index &= ~IN.EXACT_MATCH;

                /*
                 * Replace whatever's at this entry, whether it's an LN or an
                 * earlier root DIN as long as one of the following is true:
                 *
                 * - the entry is known deleted
                 * - or the LSN is earlier than the one we've just read from
                 *     the log.
                 */
                if (parent.isEntryKnownDeleted(index)) {
                    /* Be sure to clear the known deleted bit. */
                    parent.setEntry(index, inFromLog, mainTreeKey,
                                    lsn, (byte) 0);
                    replaced = true;
                } else {
                    originalLsn = parent.getLsn(index);
                    if (DbLsn.compareTo(originalLsn, lsn) < 0) {
                        parent.setEntry(index, inFromLog, mainTreeKey, lsn,
                                        parent.getState(index));
                        replaced = true;
                    }
                }
            } else {
                found = false;
            }
            success = true;
        } finally {
            if (parent != null) {
                parent.releaseLatch();
            }
            trace(detailedTraceLevel,
                  db,
                  TRACE_DUP_ROOT_REPLACE, success, inFromLog,
                  lsn, parent, found,
                  replaced, inserted, originalLsn, DbLsn.NULL_LSN, index);
        }
    }

    private void replaceOrInsertChild(DatabaseImpl db,
                                      IN inFromLog,
                                      long logLsn,
                                      long inLsn,
                                      List<TrackingInfo> trackingList,
                                      boolean requireExactMatch)
        throws DatabaseException {

        boolean inserted = false;
        boolean replaced = false;
        long originalLsn = DbLsn.NULL_LSN;
        boolean success = false;
        SearchResult result = new SearchResult();
        try {
            result = db.getTree().getParentINForChildIN
                (inFromLog,
                 requireExactMatch,
                 CacheMode.UNCHANGED,
                 -1,    // targetLevel
                 trackingList);

            /*
             * Does inFromLog exist in this parent?
             *
             * 1. No possible parent -- skip this child. It's represented
             *    by a parent that's later in the log.
             * 2. No match, but a possible parent: don't insert, all nodes
             *    are logged in such a way that they must have a possible
             *    parent (#13501)
             * 3. physical match: (LSNs same) this LSN is already in place,
             *                    do nothing.
             * 4. logical match: another version of this IN is in place.
             *                   Replace child with inFromLog if inFromLog's
             *                   LSN is greater.
             */
            if (result.parent == null) {
                return;  // case 1, no possible parent.
            }

            /* Get the key that will locate inFromLog in this parent. */
            if (result.index >= 0) {
                if (result.parent.getLsn(result.index) == logLsn) {
                    /* case 3: do nothing */

                } else {

                    /*
                     * Not an exact physical match, now need to look at child.
                     */
                    if (result.exactParentFound) {
                        originalLsn = result.parent.getLsn(result.index);

                        /* case 4: It's a logical match, replace */
                        if (DbLsn.compareTo(originalLsn, logLsn) < 0) {

                            /*
                             * It's a logical match, replace. Put the child
                             * node reference into the parent, as well as the
                             * true LSN of the IN. (If this entry is a
                             * BINDelta, the node has been updated with all the
                             * deltas, but the LSN we want to put in should be
                             * the last full LSN, not the LSN of the BINDelta)
                             */
                            result.parent.updateNode(result.index,
                                                     inFromLog,
                                                     inLsn,
                                                     null /*lnSlotKey*/);
                            replaced = true;
                        }
                    }
                    /* else case 2 */
                }
            }
            /* else case 2 */

            success = true;
        } finally {
            if (result.parent != null) {
                result.parent.releaseLatch();
            }

            trace(detailedTraceLevel, db,
                  TRACE_IN_REPLACE, success, inFromLog,
                  logLsn, result.parent,
                  result.exactParentFound, replaced, inserted,
                  originalLsn, DbLsn.NULL_LSN, result.index);
        }
    }

    /**
     * Redo a committed LN for recovery.
     *
     * <pre>
     * log LN found  | logLSN > LSN | LN is deleted | action
     *   in tree     | in tree      |               |
     * --------------+--------------+---------------+------------------------
     *     Y         |    N         |    n/a        | no action
     * --------------+--------------+---------------+------------------------
     *     Y         |    Y         |     N         | replace w/log LSN
     * --------------+--------------+---------------+------------------------
     *     Y         |    Y         |     Y         | replace w/log LSN, put
     *               |              |               | on compressor queue
     * --------------+--------------+---------------+------------------------
     *     N         |    n/a       |     N         | insert into tree
     * --------------+--------------+---------------+------------------------
     *     N         |    n/a       |     Y         | no action
     * --------------+--------------+---------------+------------------------
     *
     * </pre>
     *
     * @param location holds state about the search in the tree. Passed
     *  in from the recovery manager to reduce objection creation overhead.
     * @param lnFromLog - the new node to put in the tree.
     * @param mainKey is the key that navigates us through the main tree
     * @param dupTreeKey is the key that navigates us through the duplicate
     * tree
     * @param logLsn is the LSN from the just-read log entry
     * @param info is a recovery stats object.
     * @return the LSN found in the tree, or NULL_LSN if not found.
     */
    private long redo(DatabaseImpl db,
                      TreeLocation location,
                      LN lnFromLog,
                      byte[] mainKey,
                      byte[] dupKey,
                      long logLsn,
                      RecoveryInfo info)
        throws DatabaseException {

        boolean found = false;
        boolean replaced = false;
        boolean inserted = false;
        boolean success = false;
        try {

            /*
             * Find the BIN which is the parent of this LN.
             */
            location.reset();
            found = db.getTree().getParentBINForChildLN
                (location, mainKey, dupKey, lnFromLog,
                 true,  // splitsAllowed
                 false, // findDeletedEntries
                 true,  // searchDupTree
                 CacheMode.DEFAULT);

            if (!found && (location.bin == null)) {

                /*
                 * There is no possible parent for this LN. This tree was
                 * probably compressed away.
                 */
                success = true;
                return DbLsn.NULL_LSN;
            }

            /*
             * Now we're at the parent for this LN, whether BIN, DBIN or DIN
             */
            if (lnFromLog.containsDuplicates()) {
                if (found) {

                    /*
                     * This is a dupCountLN. It's ok if there's no DIN parent
                     * for it. [#11307].
                     */
                    DIN duplicateRoot = (DIN)
                        location.bin.fetchTarget(location.index);
                    if (DbLsn.compareTo(logLsn, location.childLsn) >= 0) {
                        /* DupCountLN needs replacing. */
                        duplicateRoot.latch();
                        duplicateRoot.updateDupCountLNRefAndNullTarget(logLsn);
                        duplicateRoot.releaseLatch();
                    }
                }
            } else {
                if (found) {

                    /*
                     * This LN is in the tree. See if it needs replacing.
                     */
                    info.lnFound++;

                    if (DbLsn.compareTo(logLsn, location.childLsn) > 0) {
                        info.lnReplaced++;
                        replaced = true;

                        /*
			 * Be sure to make the target null. We don't want this
			 * new LN resident, it will make recovery start
			 * dragging in the whole tree and will consume too much
			 * memory.
                         *
                         * Also, LN must be left null to ensure the key in the
                         * BIN slot is transactionally correct (keys are
                         * updated if necessary when the LN is fetched).
                         * [#15704]
                         */
                        location.bin.updateNode(location.index,
                                                null /*node*/,
                                                logLsn,
                                                null /*lnSlotKey*/);
                    }

                    /*
                     * If the entry in the tree is deleted, put it on the
                     * compressor queue.  Set KnownDeleted to prevent fetching
                     * a cleaned LN.
                     */
                    if (DbLsn.compareTo(logLsn, location.childLsn) >= 0 &&
                        lnFromLog.isDeleted()) {
                        location.bin.setKnownDeletedLeaveTarget
                            (location.index);
                        byte[] deletedKey = location.bin.containsDuplicates() ?
                            dupKey : mainKey;

                        /*
                         * In the case of SR 8984, the LN has no data and
                         * therefore no valid delete key. Don't compress.
                         */
                        if (deletedKey != null) {
                            db.getDbEnvironment().addToCompressorQueue
                                (location.bin,
                                 new Key(deletedKey),
                                 false); // don't wakeup compressor
                        }
                    }
                } else {

                    /*
                     * This LN is not in the tree. If it's not deleted, insert
                     * it.
                     */
                    info.lnNotFound++;
                    if (!lnFromLog.isDeleted()) {
                        info.lnInserted++;
                        inserted = true;
                        boolean insertOk =
                            insertRecovery(db, location, logLsn);
                        assert insertOk;
                    }
                }
            }

            if (!inserted) {
                /* 
                 * We're about to cast away this instantiated LN. It may
                 * have registered for some portion of the memory budget,
                 * so free that now. Specifically, this would be true
                 * for the DbFileSummaryMap in a MapLN.
                 */
                lnFromLog.releaseMemoryBudget();
            }

            success = true;
            return found ? location.childLsn : DbLsn.NULL_LSN;
        } finally {
            if (location.bin != null) {
                location.bin.releaseLatch();
            }
            trace(detailedTraceLevel, db,
                  TRACE_LN_REDO, success, lnFromLog,
                  logLsn, location.bin, found,
                  replaced, inserted,
                  location.childLsn, DbLsn.NULL_LSN, location.index);
        }
    }

    /**
     * Undo the changes to this node. Here are the rules that govern the action
     * taken.
     *
     * <pre>
     *
     * found LN in  | abortLsn is | logLsn ==       | action taken
     *    tree      | null        | LSN in tree     | by undo
     * -------------+-------------+----------------------------------------
     *      Y       |     N       |      Y          | replace w/abort LSN
     * ------------ +-------------+-----------------+-----------------------
     *      Y       |     Y       |      Y          | remove from tree
     * ------------ +-------------+-----------------+-----------------------
     *      Y       |     N/A     |      N          | no action
     * ------------ +-------------+-----------------+-----------------------
     *      N       |     N/A     |    N/A          | no action (*)
     * (*) If this key is not present in the tree, this record doesn't
     * reflect the IN state of the tree and this log entry is not applicable.
     *
     * </pre>
     * @param location holds state about the search in the tree. Passed
     *  in from the recovery manager to reduce objection creation overhead.
     * @param lnFromLog - the new node to put in the tree.
     * @param mainKey is the key that navigates us through the main tree
     * @param dupTreeKey is the key that navigates us through the duplicate
     *                   tree
     * @param logLsn is the LSN from the just-read log entry
     * @param abortLsn gives us the location of the original version of the
     *                 node
     * @param info is a recovery stats object.
     */
    public static void undo(Level traceLevel,
                            DatabaseImpl db,
                            TreeLocation location,
                            LN lnFromLog,
                            byte[] mainKey,
                            byte[] dupKey,
                            long logLsn,
                            long abortLsn,
                            boolean abortKnownDeleted,
                            RecoveryInfo info,
                            boolean splitsAllowed)
        throws DatabaseException {

        boolean found = false;
        boolean replaced = false;
        boolean success = false;

        try {

            /*
             * Find the BIN which is the parent of this LN.
             */
            location.reset();
            found = db.getTree().getParentBINForChildLN
                (location, mainKey, dupKey, lnFromLog, splitsAllowed,
                 true,  // findDeletedEntries
                 false, // searchDupTree
                 CacheMode.DEFAULT); // updateGeneration

            /*
             * Now we're at the rightful parent, whether BIN or DBIN.
             */
            if (lnFromLog.containsDuplicates()) {

                /*
                 * This is a dupCountLN. It's ok if there's no DIN parent
                 * for it. [#11307].
                 */
                if (found) {
                    DIN duplicateRoot = (DIN)
                        location.bin.fetchTarget(location.index);
                    duplicateRoot.latch();
                    try {
                        if (DbLsn.compareTo(logLsn, location.childLsn) == 0) {
                            /* DupCountLN needs replacing. */
                            duplicateRoot.
                                updateDupCountLNRefAndNullTarget(abortLsn);
                            replaced = true;
                        }
                    } finally {
                        duplicateRoot.releaseLatch();
                    }
                }
            } else {
                if (found) {
                    /* This LN is in the tree. See if it needs replacing. */
                    if (info != null) {
                        info.lnFound++;
                    }
                    boolean updateEntry =
                        DbLsn.compareTo(logLsn, location.childLsn) == 0;
                    if (updateEntry) {
                        if (abortLsn == DbLsn.NULL_LSN) {

                            /*
                             * To undo a node that was created by this txn,
                             * remove it.  If this entry is deleted, put it on
                             * the compressor queue.  Set KnownDeleted to
                             * prevent fetching a cleaned LN.
                             */
                            location.bin.
                                setKnownDeletedLeaveTarget(location.index);
                            byte[] deletedKey =
                                location.bin.containsDuplicates() ?
                                dupKey : mainKey;
                            db.getDbEnvironment().addToCompressorQueue
                                (location.bin,
                                 new Key(deletedKey),
                                 false); // don't wakeup compressor

                        } else {

			    /*
			     * Apply the log record by updating the in memory
			     * tree slot to contain the abort LSN and abort
			     * Known Deleted flag.  The LN is set to null so
                             * that it will be fetched later by abort LSN.
                             *
                             * Also, the LN must be left null to ensure the
                             * key in the BIN slot is transactionally correct
                             * (the key is updated if necessary when the LN is
                             * fetched).  [#15704]
			     */
			    if (info != null) {
				info.lnReplaced++;
			    }
			    replaced = true;
			    location.bin.updateNode(location.index,
						    null /*node*/,
						    abortLsn,
                                                    null /*lnSlotKey*/);
			    if (abortKnownDeleted) {
				location.bin.setKnownDeleted(location.index);
			    } else {
				location.bin.clearKnownDeleted(location.index);
			    }
			}

                        /*
                         * We must clear the PendingDeleted flag for
                         * non-deleted entries.  Clear it unconditionally,
                         * since KnownDeleted will be set above for a deleted
                         * entry. [#12885]
                         */
                        location.bin.clearPendingDeleted(location.index);
                    }

                } else {

                    /*
                     * This LN is not in the tree.  Just make a note of it.
                     */
                    if (info != null) {
                        info.lnNotFound++;
                    }
                }
            }

            success = true;
        } finally {

	    if (location.bin != null) {
		location.bin.releaseLatch();
	    }

            trace(traceLevel, db, TRACE_LN_UNDO, success, lnFromLog,
                  logLsn, location.bin, found, replaced, false,
                  location.childLsn, abortLsn, location.index);
        }
    }

    /**
     * Inserts a LN into the tree for recovery redo processing.  In this
     * case, we know we don't have to lock when checking child LNs for deleted
     * status (there can be no other thread running on this tree) and we don't
     * have to log the new entry. (it's in the log already)
     *
     * @param db
     * @param location this embodies the parent bin, the index, the key that
     * represents this entry in the bin.
     * @param logLsn LSN of this current ln
     * @param key to use when creating a new ChildReference object.
     * @return true if LN was inserted, false if it was a duplicate
     * duplicate or if an attempt was made to insert a duplicate when
     * allowDuplicates was false.
     */
    private static boolean insertRecovery(DatabaseImpl db,
                                          TreeLocation location,
                                          long logLsn)
        throws DatabaseException {

        /*
         * Make a child reference as a candidate for insertion.  The LN is null
         * to avoid pulling the entire tree into memory.
         *
         * Also, the LN must be left null to ensure the key in the BIN slot is
         * transactionally correct (keys are updated if necessary when the LN
         * is fetched).  [#15704]
         */
        ChildReference newLNRef =
            new ChildReference(null, location.lnKey, logLsn);

        BIN parentBIN = location.bin;
        int entryIndex = parentBIN.insertEntry1(newLNRef);

        if ((entryIndex & IN.INSERT_SUCCESS) == 0) {

            /*
             * Entry may have been a duplicate. Insertion was not successful.
             */
            entryIndex &= ~IN.EXACT_MATCH;

            boolean canOverwrite = false;
            if (parentBIN.isEntryKnownDeleted(entryIndex)) {
                canOverwrite = true;
            } else {

                /*
                 * Read the LN that's in this slot to check for deleted
                 * status.  No need to lock, since this is recovery.  If
                 * fetchTarget returns null, a deleted LN was cleaned.
                 */
                LN currentLN = (LN) parentBIN.fetchTarget(entryIndex);

                if (currentLN == null || currentLN.isDeleted()) {
                    canOverwrite = true;
                }

                /*
                 * Evict the target again manually, to reduce memory
                 * consumption while the evictor is not running.
                 */
                parentBIN.updateNode(entryIndex, null /*node*/,
                                     null /*lnSlotKey*/);
            }

            if (canOverwrite) {

                /*
                 * Note that the LN must be left null to ensure the key in the
                 * BIN slot is transactionally correct (keys are updated if
                 * necessary when the LN is fetched).  [#15704]
                 */
                parentBIN.updateEntry(entryIndex, null, logLsn,
                                      location.lnKey);
                parentBIN.clearKnownDeleted(entryIndex);
                location.index = entryIndex;
                return true;
            } else {
                return false;
            }
        }
        location.index = entryIndex & ~IN.INSERT_SUCCESS;
        return true;
    }

    /**
     * Update utilization info during redo.
     *
     * There are cases where we do not count the previous version of an LN as
     * obsolete when that obsolete LN occurs prior to the recovery interval.
     * This happens when a later version of the LN is current in the tree
     * because its parent IN has been flushed non-provisionally after it.  The
     * old version of the LN is not in the tree so we never encounter it during
     * recovery and cannot count it as obsolete.  For example:
     *
     * 100 LN-A
     * checkpoint occurred (ckpt begin, flush, ckpt end)
     * 200 LN-A
     * 300 BIN parent of 200
     * 400 IN parent of 300, non-provisional via a sync
     *
     * no utilization info is flushed
     * no checkpoint
     * crash and recover
     *
     * 200 is the current LN-A in the tree.  When we redo 200 we do not count
     * anything as obsolete because the log and tree LSNs are equal.  100 is
     * never counted obsolete because it is not in the recovery interval.
     *
     * The same thing occurs when a deleted LN is replayed and the old version
     * is not found in the tree because it was compressed and the IN was
     * flushed non-provisionally.
     *
     * In these cases we may be able to count the abortLsn as obsolete but that
     * would not work for non-transactional entries.
     */
    private void redoUtilizationInfo(long logLsn,
                                     long treeLsn,
                                     long commitLsn,
                                     long abortLsn,
                                     boolean abortKnownDeleted,
                                     int logEntrySize,
                                     byte[] key,
                                     LN ln,
                                     DatabaseImpl db,
                                     TxnNodeId txnNodeId,
                                     Set<TxnNodeId> countedAbortLsnNodes)
        throws DatabaseException {

        /*
         * If the LN is marked deleted and its LSN follows the FileSummaryLN
         * for its file, count it as obsolete.
         *
         * Inexact counting is used to save resources because the cleaner knows
         * that all deleted LNs are obsolete.
         */
        if (ln.isDeleted()) {
            tracker.countObsoleteIfUncounted
                (logLsn, logLsn, null, logEntrySize, db.getId(),
                 false /*countExact*/);
        }

        /* Was the LN found in the tree? */
        if (treeLsn != DbLsn.NULL_LSN) {
            int cmpLogLsnToTreeLsn = DbLsn.compareTo(logLsn, treeLsn);

            /*
             * If the oldLsn and newLsn differ and the newLsn follows the
             * FileSummaryLN for the file of the oldLsn, count the oldLsn as
             * obsolete.
             *
             * Use exact counting only if the transaction is committed.  A
             * prepared or resurrected transaction may be committed or aborted
             * later on.  We perform obsolete counting as if a commit will
             * occur to ensure cleaning will occur, but we count inexact to
             * prevent LogFileNotFound in case an abort occurs.  [#17022]
             */
            if (cmpLogLsnToTreeLsn != 0) {
                long newLsn = (cmpLogLsnToTreeLsn < 0) ? treeLsn : logLsn;
                long oldLsn = (cmpLogLsnToTreeLsn > 0) ? treeLsn : logLsn;
                int oldSize = (oldLsn == logLsn) ? logEntrySize : 0;
                tracker.countObsoleteIfUncounted
                    (oldLsn, newLsn, null,
                     tracker.fetchLNSize(oldSize, oldLsn), db.getId(),
                     commitLsn != DbLsn.NULL_LSN /*countExact*/);
            }

            /*
             * If the logLsn is equal to or precedes the treeLsn and the entry
             * has an abortLsn that was not previously deleted, consider the
             * set of entries for the given node.  If the logLsn is the first
             * in the set that follows the FileSummaryLN of the abortLsn, count
             * the abortLsn as obsolete.
             */
            if (cmpLogLsnToTreeLsn <= 0 &&
                abortLsn != DbLsn.NULL_LSN &&
                !abortKnownDeleted &&
                !countedAbortLsnNodes.contains(txnNodeId)) {

                /*
                 * We have not counted this abortLsn yet.  Count abortLsn as
                 * obsolete if commitLsn follows the FileSummaryLN of the
                 * abortLsn, since the abortLsn is counted obsolete at commit.
                 * The abortLsn is only an approximation of the prior LSN, so
                 * use inexact counting.  Since this is relatively rare, a zero
                 * entry size (use average size) is acceptable.
                 *
                 * Note that commitLsn may be null if this is a prepared or
                 * resurrected HA Txn. [#16375]
                 */
                if (commitLsn != DbLsn.NULL_LSN) {
                    tracker.countObsoleteIfUncounted
                            (abortLsn, commitLsn, null, 0, db.getId(),
                             false /*countExact*/);
                    /* Don't count this abortLsn (this node) again. */
                    countedAbortLsnNodes.add(txnNodeId);
                }
            }
        }
    }

    /**
     * Update utilization info during recovery undo (not abort undo).
     */
    private void undoUtilizationInfo(LN ln,
                                     DatabaseImpl db,
                                     long logLsn,
                                     long abortLsn,
                                     boolean abortKnownDeleted,
                                     int logEntrySize,
                                     TxnNodeId txnNodeId,
                                     Map<TxnNodeId,Long> countedFileSummaries,
                                     Set<TxnNodeId> countedAbortLsnNodes) {
        /*
         * Count the logLsn as obsolete if it follows the FileSummaryLN for the
         * file of its Lsn.
         */
        boolean counted = tracker.countObsoleteIfUncounted
            (logLsn, logLsn, null, logEntrySize, db.getId(),
             true /*countExact*/);

        /*
         * Consider the latest LSN for the given node that precedes the
         * FileSummaryLN for the file of its LSN.  Count this LSN as obsolete
         * if it is not a deleted LN.
         */
        if (!counted) {
            Long logFileNum = Long.valueOf(DbLsn.getFileNumber(logLsn));
            Long countedFile = countedFileSummaries.get(txnNodeId);
            if (countedFile == null ||
                countedFile.longValue() > logFileNum.longValue()) {

                /*
                 * We encountered a new file number and the FsLsn follows the
                 * logLsn.
                 */
                if (!ln.isDeleted()) {
                    tracker.countObsoleteUnconditional
                        (logLsn, null, logEntrySize, db.getId(),
                         true /*countExact*/);
                }
                /* Don't count this file again. */
                countedFileSummaries.put(txnNodeId, logFileNum);
            }
        }
    }

    /**
     * Remove all temporary databases that were encountered as MapLNs during
     * recovery undo/redo.  A temp DB needs to be removed when it is not closed
     * (closing a temp DB removes it) prior to a crash.  We ensure that the
     * MapLN for every open temp DBs is logged each checkpoint interval.
     */
    private void removeTempDbs()
        throws DatabaseException {

        DbTree dbMapTree = env.getDbTree();
        BasicLocker locker =
	    BasicLocker.createBasicLocker(env, false /*noWait*/,
					  true /*noAPIReadLock*/);
        boolean operationOk = false;
        try {
            Iterator<DatabaseId> removeDbs = tempDbIds.iterator();
            while (removeDbs.hasNext()) {
                DatabaseId dbId = removeDbs.next();
                DatabaseImpl db = dbMapTree.getDb(dbId);
                dbMapTree.releaseDb(db); // Decrement use count.
                if (db != null) {
                    assert db.isTemporary();
                    if (!db.isDeleted()) {
                        env.getDbTree().dbRemove(locker,
                                                 db.getName(),
                                                 db.getId());
                    }
                }
            }
            operationOk = true;
        } catch (Error E) {
            env.invalidate(E);
            throw E;
        } finally {
            locker.operationEnd(operationOk);
        }
    }

    /**
     * Concoct a header for the recovery pass trace info.
     */
    private String passStartHeader(int passNum) {
        return "Recovery Pass " + passNum + " start: ";
    }

    /**
     * Concoct a header for the recovery pass trace info.
     */
    private String passEndHeader(int passNum, long start, long end) {
        return "Recovery Pass " + passNum + " end (" +
            (end-start) + "): ";
    }

    /**
     * Send trace messages to the java.util.logger. Don't rely on the logger
     * alone to conditionalize whether we send this message, we don't even want
     * to construct the message if the level is not enabled. This is used to
     * construct verbose trace messages for individual log entry processing.
     */
    private static void trace(Level level,
                              DatabaseImpl database,
                              String debugType,
                              boolean success,
                              Node node,
                              long logLsn,
                              IN parent,
                              boolean found,
                              boolean replaced,
                              boolean inserted,
                              long replacedLsn,
                              long abortLsn,
                              int index) {
        Logger logger = database.getDbEnvironment().getLogger();
        Level useLevel= level;
        if (!success) {
            useLevel = Level.SEVERE;
        }
        if (logger.isLoggable(useLevel)) {
            StringBuffer sb = new StringBuffer();
            sb.append(debugType);
            sb.append(" success=").append(success);
            sb.append(" node=");
            sb.append(node.getNodeId());
            sb.append(" lsn=");
            sb.append(DbLsn.getNoFormatString(logLsn));
            if (parent != null) {
                sb.append(" parent=").append(parent.getNodeId());
            }
            sb.append(" found=");
            sb.append(found);
            sb.append(" replaced=");
            sb.append(replaced);
            sb.append(" inserted=");
            sb.append(inserted);
            if (replacedLsn != DbLsn.NULL_LSN) {
                sb.append(" replacedLsn=");
                sb.append(DbLsn.getNoFormatString(replacedLsn));
            }
            if (abortLsn != DbLsn.NULL_LSN) {
                sb.append(" abortLsn=");
                sb.append(DbLsn.getNoFormatString(abortLsn));
            }
            sb.append(" index=").append(index);
            logger.log(useLevel, sb.toString());
        }
    }

    /**
     * Send trace messages to the java.util.logger. Don't rely on the logger
     * alone to conditionalize whether we send this message, we don't even want
     * to construct the message if the level is not enabled.
     */
    private void traceINDeleteReplay(long nodeId,
                                     long logLsn,
                                     boolean found,
                                     boolean deleted,
                                     int index,
                                     boolean isDuplicate) {
        Logger logger = env.getLogger();
        if (logger.isLoggable(detailedTraceLevel)) {
            StringBuffer sb = new StringBuffer();
            sb.append((isDuplicate) ?
                      TRACE_IN_DUPDEL_REPLAY :
                      TRACE_IN_DEL_REPLAY);
            sb.append(" node=").append(nodeId);
            sb.append(" lsn=").append(DbLsn.getNoFormatString(logLsn));
            sb.append(" found=").append(found);
            sb.append(" deleted=").append(deleted);
            sb.append(" index=").append(index);
            logger.log(detailedTraceLevel, sb.toString());
        }
    }

    private void traceAndThrowException(long badLsn,
                                        String method,
                                        Exception originalException)
        throws DatabaseException {
        String badLsnString = DbLsn.getNoFormatString(badLsn);
        Tracer.trace(env,
                     "RecoveryManager",
                     method,
                     "last LSN = " + badLsnString,
                     originalException);
        throw new DatabaseException("last LSN=" + badLsnString,
                                    originalException);
    }

    /**
     * Log trace information about root deletions, called by INCompressor and
     * recovery.
     */
    public static void traceRootDeletion(Level level, DatabaseImpl database) {
        Logger logger = database.getDbEnvironment().getLogger();
        if (logger.isLoggable(level)) {
            StringBuffer sb = new StringBuffer();
            sb.append(TRACE_ROOT_DELETE);
            sb.append(" Dbid=").append(database.getId());
            logger.log(level, sb.toString());
        }
    }
}
