/** @return true if the in-memory root was replaced. */
public IN doWork(ChildReference root) throws DatabaseException {
if (root == null) {
return null;
}
IN rootIN = (IN) root.fetchTarget(db, null);
rootIN.latch();
try {
if (rootIN.getNodeId() == target.getNodeId()) {
/*
* stillRoot handles race condition where root
* splits after target's latch is release.
*/
stillRoot = true;
if (rootIN.getDirty()) {
DbLsn newLsn = rootIN.log(logManager);
root.setLsn(newLsn);
flushed = true;
}
}
} finally {
rootIN.releaseLatch();
}
return null;
}
/**
* Flush the nodes in order, from the lowest level to highest level. As a flush dirties its
* parent, add it to the dirty map, thereby cascading the writes up the tree. If flushAll wasn't
* specified, we need only cascade up to the highest level that existed before the checkpointing
* started.
*
* <p>Note that all but the top level INs and the BINDeltas are logged provisionally. That's
* because we don't need to process lower INs because the higher INs will end up pointing at them.
*/
private void flushDirtyNodes(boolean flushAll, boolean allowDeltas, boolean flushExtraLevel)
throws DatabaseException {
LogManager logManager = envImpl.getLogManager();
SortedMap dirtyMap = selectDirtyINs(flushAll, flushExtraLevel);
while (dirtyMap.size() > 0) {
/* Work on one level's worth of nodes in ascending level order. */
Integer currentLevel = (Integer) dirtyMap.firstKey();
boolean logProvisionally = (currentLevel.intValue() != highestFlushLevel);
Set nodeSet = (Set) dirtyMap.get(currentLevel);
Iterator iter = nodeSet.iterator();
/* Flush all those nodes */
while (iter.hasNext()) {
IN target = (IN) iter.next();
target.latch();
boolean triedToFlush = false;
/*
* Only flush the ones that are still dirty -- some
* may have been written out by the evictor. Also
* check if the db is still valid -- since INs of
* deleted databases are left on the in-memory tree
* until the evictor lazily clears them out, there may
* be dead INs around.
*/
if (target.getDirty() && (!target.getDatabase().getIsDeleted())) {
flushIN(target, logManager, dirtyMap, logProvisionally, allowDeltas);
triedToFlush = true;
} else {
target.releaseLatch();
}
Tracer.trace(
Level.FINE,
envImpl,
"Checkpointer: node="
+ target.getNodeId()
+ " level="
+ Integer.toHexString(target.getLevel())
+ " flushed="
+ triedToFlush);
}
/* We're done with this level. */
dirtyMap.remove(currentLevel);
/* We can stop at this point. */
if (currentLevel.intValue() == highestFlushLevel) {
break;
}
}
}
/** Flush the target IN. */
private void flushIN(
IN target, LogManager logManager, Map dirtyMap, boolean logProvisionally, boolean allowDeltas)
throws DatabaseException {
DatabaseImpl db = target.getDatabase();
Tree tree = db.getTree();
boolean targetWasRoot = false;
if (target.isDbRoot()) {
/* We're trying to flush the root. */
target.releaseLatch();
RootFlusher flusher = new RootFlusher(db, logManager, target);
tree.withRootLatched(flusher);
boolean flushed = flusher.getFlushed();
/*
* We have to check if the root split between target.releaseLatch
* and the execution of the root flusher. If it did split, this
* target has to get handled like a regular node.
*/
targetWasRoot = flusher.stillRoot();
/*
* Update the tree's owner, whether it's the env root or the
* dbmapping tree.
*/
if (flushed) {
DbTree dbTree = db.getDbEnvironment().getDbMapTree();
dbTree.modifyDbRoot(db);
nFullINFlushThisRun++;
nFullINFlush++;
}
if (!targetWasRoot) {
/*
* re-latch for another attempt, now that this is no longer
* the root.
*/
target.latch();
}
}
if (!targetWasRoot) {
SearchResult result = tree.getParentINForChildIN(target, true);
/*
* Found a parent, do the flush. If no parent found, the
* compressor deleted this item before we got to processing it.
*/
if (result.exactParentFound) {
try {
ChildReference entry = result.parent.getEntry(result.index);
IN renewedTarget = (IN) entry.fetchTarget(db, result.parent);
renewedTarget.latch();
DbLsn newLsn = null;
try {
/* Still dirty? */
if (renewedTarget.getDirty()) {
if (allowDeltas) {
newLsn = renewedTarget.logAllowDeltas(logManager, logProvisionally);
if (newLsn == null) {
nDeltaINFlushThisRun++;
nDeltaINFlush++;
}
} else {
newLsn = renewedTarget.log(logManager, logProvisionally);
}
}
} finally {
renewedTarget.releaseLatch();
}
/* Update parent if logging occurred */
if (newLsn != null) {
nFullINFlushThisRun++;
nFullINFlush++;
if (renewedTarget instanceof BIN) {
nFullBINFlush++;
}
result.parent.updateEntry(result.index, newLsn);
addToDirtyMap(dirtyMap, result.parent);
}
} finally {
result.parent.releaseLatch();
}
}
}
}
/*
* Scan the INList for all dirty INs. Arrange them in level sorted
* map for level ordered flushing.
*/
private SortedMap selectDirtyINs(boolean flushAll, boolean flushExtraLevel)
throws DatabaseException {
SortedMap newDirtyMap = new TreeMap();
INList inMemINs = envImpl.getInMemoryINs();
inMemINs.latchMajor();
/*
* Opportunistically recalculate the environment wide memory
* count. Incurs no extra cost because we're walking the IN
* list anyway. Not the best in terms of encapsulation as
* prefereably all memory calculations are done in
* MemoryBudget, but done this way to avoid any extra
* latching.
*/
long totalSize = 0;
MemoryBudget mb = envImpl.getMemoryBudget();
try {
Iterator iter = inMemINs.iterator();
while (iter.hasNext()) {
IN in = (IN) iter.next();
in.latch();
totalSize = mb.accumulateNewUsage(in, totalSize);
boolean isDirty = in.getDirty();
in.releaseLatch();
if (isDirty) {
Integer level = new Integer(in.getLevel());
Set dirtySet;
if (newDirtyMap.containsKey(level)) {
dirtySet = (Set) newDirtyMap.get(level);
} else {
dirtySet = new HashSet();
newDirtyMap.put(level, dirtySet);
}
dirtySet.add(in);
}
}
// Later release: refresh env count.
// mb.refreshCacheMemoryUsage(totalSize);
/*
* If we're flushing all for cleaning, we must flush to
* the point that there are no nodes with LSNs in the
* cleaned files. We could figure this out by perusing
* every node to see what children it has, but that's so
* expensive that instead we'll flush to the root.
*/
if (newDirtyMap.size() > 0) {
if (flushAll) {
highestFlushLevel = envImpl.getDbMapTree().getHighestLevel();
} else {
highestFlushLevel = ((Integer) newDirtyMap.lastKey()).intValue();
if (flushExtraLevel) {
highestFlushLevel += 1;
}
}
}
} finally {
inMemINs.releaseMajorLatchIfHeld();
}
return newDirtyMap;
}