public OCachePointer load(long fileId, long pageIndex) throws IOException {
synchronized (syncObject) {
final GroupKey groupKey = new GroupKey(fileId, pageIndex >>> 4);
lockManager.acquireLock(Thread.currentThread(), groupKey, OLockManager.LOCK.SHARED);
try {
final WriteGroup writeGroup = writeGroups.get(groupKey);
OCachePointer pagePointer;
if (writeGroup == null) {
pagePointer = cacheFileContent(fileId, pageIndex);
pagePointer.incrementReferrer();
return pagePointer;
}
final int entryIndex = (int) (pageIndex & 15);
pagePointer = writeGroup.pages[entryIndex];
if (pagePointer == null) pagePointer = cacheFileContent(fileId, pageIndex);
pagePointer.incrementReferrer();
return pagePointer;
} finally {
lockManager.releaseLock(Thread.currentThread(), groupKey, OLockManager.LOCK.SHARED);
}
}
}
public Future store(final long fileId, final long pageIndex, final OCachePointer dataPointer) {
Future future = null;
synchronized (syncObject) {
final GroupKey groupKey = new GroupKey(fileId, pageIndex >>> 4);
lockManager.acquireLock(Thread.currentThread(), groupKey, OLockManager.LOCK.EXCLUSIVE);
try {
WriteGroup writeGroup = writeGroups.get(groupKey);
if (writeGroup == null) {
writeGroup = new WriteGroup(System.currentTimeMillis());
writeGroups.put(groupKey, writeGroup);
}
int entryIndex = (int) (pageIndex & 15);
if (writeGroup.pages[entryIndex] == null) {
dataPointer.incrementReferrer();
writeGroup.pages[entryIndex] = dataPointer;
cacheSize.incrementAndGet();
} else {
if (!writeGroup.pages[entryIndex].equals(dataPointer)) {
writeGroup.pages[entryIndex].decrementReferrer();
dataPointer.incrementReferrer();
writeGroup.pages[entryIndex] = dataPointer;
}
}
writeGroup.recencyBit = true;
} finally {
lockManager.releaseLock(Thread.currentThread(), groupKey, OLockManager.LOCK.EXCLUSIVE);
}
if (cacheSize.get() > cacheMaxSize) {
future = commitExecutor.submit(new PeriodicFlushTask());
}
return future;
}
}
