Enforce max memory for DeltaWindow.

Previously, memory limits were enforced at the start of each iteration
of the delta search, based on objects that were currently loaded in
memory. However, new objects added to the window may be expanded in a
future iteration of the search and thus were not accounted for correctly
at the start of the search. To fix this, memory limits are now enforced
before each object is loaded.

Change-Id: I898ab43e7bf5ee7189831f3a68bb9385ae694b8f
This commit is contained in:
Colby Ranger 2012-12-27 08:48:39 -08:00
parent 03d50dc50b
commit 51beee5568
1 changed files with 24 additions and 0 deletions

View File

@ -164,6 +164,14 @@ private static long estimateSize(ObjectToPack ent) {
return DeltaIndex.estimateIndexSize(ent.getWeight());
}
private static long estimateIndexSize(DeltaWindowEntry ent) {
if (ent.buffer == null)
return estimateSize(ent.object);
int len = ent.buffer.length;
return DeltaIndex.estimateIndexSize(len) - len;
}
private void clear(DeltaWindowEntry ent) {
if (ent.index != null)
loaded -= ent.index.getIndexSize();
@ -420,6 +428,8 @@ private DeltaIndex index(DeltaWindowEntry ent)
IOException, LargeObjectException {
DeltaIndex idx = ent.index;
if (idx == null) {
checkLoadable(ent, estimateIndexSize(ent));
try {
idx = new DeltaIndex(buffer(ent));
} catch (OutOfMemoryError noMemory) {
@ -439,6 +449,8 @@ private byte[] buffer(DeltaWindowEntry ent) throws MissingObjectException,
IncorrectObjectTypeException, IOException, LargeObjectException {
byte[] buf = ent.buffer;
if (buf == null) {
checkLoadable(ent, ent.size());
buf = PackWriter.buffer(config, reader, ent.object);
if (0 < maxMemory)
loaded += buf.length;
@ -447,6 +459,18 @@ private byte[] buffer(DeltaWindowEntry ent) throws MissingObjectException,
return buf;
}
private void checkLoadable(DeltaWindowEntry ent, long need) {
int tail = next(resSlot);
while (maxMemory < loaded + need) {
DeltaWindowEntry cur = window[tail];
clear(cur);
if (cur == ent)
throw new LargeObjectException.ExceedsLimit(
maxMemory, loaded + need);
tail = next(tail);
}
}
private Deflater deflater() {
if (deflater == null)
deflater = new Deflater(config.getCompressionLevel());