threads / patch / 19091

patchFix performance problem recently introduced to DeltaPackedObjectLoader

Subject: [JGIT PATCH] Fix performance problem recently introduced to DeltaPackedObjectLoader

## tl;dr

One message between Apr 27, 2009 and Apr 27, 2009. Diffs are folded; open one to read it.

replies: 0people: 1as markdown or json

Shawn O. Pearce· Apr 27, 2009, 21:44 UTC · lore

In fe6c8248e1ed6bd9db76a8314103081a02d55393 ("Fully materialize an ObjectLoader before returning it from ObjectDatabase") I missed a crucial return call here in DeltaPackedObjectLoadeder. That one missing line caused cache hits in the UnpackedObjectCache to then fall through and unpack the delta base, and apply the delta onto it, ignoring the fact that we had a successful cache hit.

When packing and serving e.g. the Linux kernel repository this resulted in a 10x increase in the number of WindowCache.get() invocations we saw, as the UnpackedObjectCache was useless.

Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
---
 .../spearce/jgit/lib/DeltaPackedObjectLoader.java  |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
Show changes to org.spearce.jgit/src/org/spearce/jgit/lib/DeltaPackedObjectLoader.java +1 −0
diff --git a/org.spearce.jgit/src/org/spearce/jgit/lib/DeltaPackedObjectLoader.java b/org.spearce.jgit/src/org/spearce/jgit/lib/DeltaPackedObjectLoader.java
index 8194d94..7d3f30d 100644
--- a/org.spearce.jgit/src/org/spearce/jgit/lib/DeltaPackedObjectLoader.java
+++ b/org.spearce.jgit/src/org/spearce/jgit/lib/DeltaPackedObjectLoader.java
@@ -69,6 +69,7 @@ public void materialize(final WindowCursor curs) throws IOException {
 				objectType = cache.type;
 				objectSize = cache.data.length;
 				cachedBytes = cache.data;
+				return;
 			}
 		}
 
-- 
1.6.3.rc1.205.g37f8

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