/**
* Create a database environment to represent the data in envHome. dbHome. Properties from the
* je.properties file in that directory are used to initialize the system wide property bag.
* Properties passed to this method are used to influence the open itself.
*
* @param envHome absolute path of the database environment home directory
* @param envConfig
* @throws DatabaseException on all other failures
*/
public EnvironmentImpl(File envHome, EnvironmentConfig envConfig) throws DatabaseException {
try {
this.envHome = envHome;
envState = DbEnvState.INIT;
/* Set up configuration parameters */
configManager = new DbConfigManager(envConfig);
configObservers = new ArrayList();
addConfigObserver(this);
/*
* Decide on memory budgets based on environment config params and
* memory available to this process.
*/
memoryBudget = new LogBufferBudget(this, configManager);
/*
* Set up debug logging. Depending on configuration, add handlers,
* set logging level.
*/
// envLogger = initLogger(envHome);
/*
* Essential services. These must exist before recovery.
*/
hook_readProperties(configManager);
forcedYield = configManager.getBoolean(EnvironmentParams.ENV_FORCED_YIELD);
isNoLocking = !(configManager.getBoolean(EnvironmentParams.ENV_INIT_LOCKING));
isReadOnly = configManager.getBoolean(EnvironmentParams.ENV_RDONLY);
fileManager = new FileManager(this, envHome, isReadOnly);
if (!envConfig.getAllowCreate() && !fileManager.filesExist()) {
throw new DatabaseException(
"Enviroment creation isn't allowed, "
+ " but there is no pre-existing "
+ " environment in "
+ envHome);
}
logManager = new SyncedLogManager(this, isReadOnly);
inMemoryINs = new INList(this);
txnManager = new TxnManager(this);
/*
* Make sure that either log-size-based or time-based checkpointing is
* enabled.
*/
checkpointer = new Checkpointer(this);
cleaner = new Cleaner(this, "Cleaner");
/*
* Daemons are always made here, but only started after recovery. We
* want them to exist so we can call them programatically even if
* the daemon thread is not started.
*/
createDaemons();
/*
* Recovery will recreate the dbMapTree from the log if it exists.
*/
dbMapTree = new DbTree(this);
referenceCount = 0;
/*
* Do not do recovery and start daemons if this environment is for a
* utility.
*/
if (configManager.getBoolean(EnvironmentParams.ENV_RECOVERY)) {
/*
* Run recovery. Note that debug logging to the database log is
* disabled until recovery is finished.
*/
try {
RecoveryManager recoveryManager = new RecoveryManager(this);
lastRecoveryInfo = recoveryManager.recover(isReadOnly);
} finally {
try {
/* Flush to get all exception tracing out to the log. */
logManager.flush();
fileManager.clear();
} catch (IOException e) {
throw new DatabaseException(e.getMessage());
}
}
} else {
isReadOnly = true;
noComparators = true;
}
/* Start daemons after recovery. */
runOrPauseDaemons(configManager);
/*
* Cache a few critical values. We keep our timeout in millis
* instead of microseconds because Object.wait takes millis.
*/
lockTimeout = PropUtil.microsToMillis(configManager.getLong(EnvironmentParams.LOCK_TIMEOUT));
txnTimeout = PropUtil.microsToMillis(configManager.getLong(EnvironmentParams.TXN_TIMEOUT));
/* Mark as open. */
open();
} catch (DatabaseException e) {
/* Release any environment locks if there was a problem. */
if (fileManager != null) {
try {
fileManager.close();
} catch (IOException IOE) {
/*
* Klockwork - ok Eat it, we want to throw the original
* exception.
*/
}
}
throw e;
}
}
/**
* Rollback the changes to this txn's write locked nodes up to but not including the entry at the
* specified matchpoint. When we log a transactional entry, we record the LSN of the original,
* before-this-transaction version as the abort LSN. This means that if there are multiple updates
* to a given record in a single transaction, each update only references that original version
* and its true predecessor.
*
* <p>This was done to streamline abort processing, so that an undo reverts directly to the
* original version rather than stepping through all the intermediates. The intermediates are
* skipped. However, undo to a matchpoint may need to stop at an intermediate point, so we need to
* create a true chain of versions.
*
* <p>To do so, we read the transaction backwards from the last logged LSN to reconstruct a
* transaction chain that links intermediate versions of records. For example, suppose our
* transaction looks like this and that we are undoing up to LSN 250
*
* <p>lsn=100 node=A (version 1) lsn=200 node=B (version 1) <-- matchpointLsn lsn=300 node=C
* (version 1) lsn=400 node=A (version 2) lsn=500 node=B (version 2) lsn=600 node=A (version 3)
* lsn=700 node=A (version 4)
*
* <p>To setup the old versions, We walk from LSN 700 -> 100 700 (A) rolls back to 600 600 (A)
* rolls back to 400 500 (B) rolls back to 200 400 (A) rolls back to 100 300 (C) rolls back to an
* empty slot (NULL_LSN).
*
* <p>A partial rollback also requires resetting the lastLoggedLsn field, because these operations
* are no longer in the btree and their on-disk entries are no longer valid.
*
* <p>Lastly, the appropriate write locks must be released.
*
* @param matchpointLsn the rollback should go up to but not include this LSN.
*/
private void undoWrites(long matchpointLsn, List<Long> rollbackLsns) throws DatabaseException {
/*
* Generate a map of nodeId->List of intermediate LSNs for this node.
* to re-create the transaction chain.
*/
TreeLocation location = new TreeLocation();
Long undoLsn = lastLoggedLsn;
TxnChain chain = new TxnChain(undoLsn, id, matchpointLsn, undoDatabases, envImpl);
try {
while ((undoLsn != DbLsn.NULL_LSN) && DbLsn.compareTo(undoLsn, matchpointLsn) > 0) {
UndoReader undo = new UndoReader(envImpl, undoLsn, undoDatabases);
RevertInfo revertTo = chain.pop();
logFinest(undoLsn, undo, revertTo);
/*
* When we undo this log entry, we've logically truncated
* it from the log. Remove it from the btree and mark it
* obsolete.
*/
RecoveryManager.rollbackUndo(logger, Level.FINER, undo, revertTo, location, undoLsn);
countObsoleteInexact(undoLsn, undo);
rollbackLsns.add(undoLsn);
/*
* Move on to the previous log entry for this txn and update
* what is considered to be the end of the transaction chain.
*/
undoLsn = undo.logEntry.getUserTxn().getLastLsn();
lastLoggedLsn = undoLsn;
}
/*
* Correct the fields which hold LSN and VLSN state that may
* now be changed.
*/
lastApplied = chain.getLastValidVLSN();
if (!updateLoggedForTxn()) {
firstLoggedLsn = NULL_LSN;
}
} catch (DatabaseException e) {
LoggerUtils.traceAndLogException(
envImpl, "Txn", "undo", "For LSN=" + DbLsn.getNoFormatString(undoLsn), e);
throw e;
} catch (RuntimeException e) {
throw EnvironmentFailureException.unexpectedException(
"Txn undo for LSN=" + DbLsn.getNoFormatString(undoLsn), e);
}
if (lastLoggedLsn == DbLsn.NULL_LSN) {
/*
* The whole txn is rolled back, and it may not appear again. This
* is the equivalent of an abort. Do any delete processing for an
* abort which is needed.
*
* Set database state for deletes before releasing any write
* locks.
*/
setDeletedDatabaseState(false);
}
/* Clear any write locks that are no longer needed. */
clearWriteLocks(chain.getRemainingLockedNodes());
}
