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[JGIT PATCH 05/23] Change walker based fetch to use TreeWalk's MutableObjectId accessor

From
Shawn O. Pearce <spearce@spearce.org>
Date
Dec 25, 2008, 02:11 UTC
Message-ID
<1230171079-17156-6-git-send-email-spearce@spearce.org>
In-Reply-To
<1230171079-17156-5-git-send-email-spearce@spearce.org>

Fetch time is usually dominated by network traffic, but while marking objects reachable locally we can still benefit from the reduction in object allocations this variant of getObjectId offers.

Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
---
 .../jgit/transport/WalkFetchConnection.java        |   29 +++++++++++--------
 1 files changed, 17 insertions(+), 12 deletions(-)
diff --git a/org.spearce.jgit/src/org/spearce/jgit/transport/WalkFetchConnection.java b/org.spearce.jgit/src/org/spearce/jgit/transport/WalkFetchConnection.java
index 91c5ea8..6300f10 100644
--- a/org.spearce.jgit/src/org/spearce/jgit/transport/WalkFetchConnection.java
+++ b/org.spearce.jgit/src/org/spearce/jgit/transport/WalkFetchConnection.java
@@ -59,6 +59,7 @@
 import org.spearce.jgit.lib.AnyObjectId;
 import org.spearce.jgit.lib.Constants;
 import org.spearce.jgit.lib.FileMode;
+import org.spearce.jgit.lib.MutableObjectId;
 import org.spearce.jgit.lib.ObjectChecker;
 import org.spearce.jgit.lib.ObjectId;
 import org.spearce.jgit.lib.PackIndex;
@@ -152,6 +153,8 @@
 	 */
 	private final Set<String> packsConsidered;
 
+	private final MutableObjectId idBuffer = new MutableObjectId();
+
 	/**
 	 * Errors received while trying to obtain an object.
 	 * <p>
@@ -300,16 +303,17 @@ private void processTree(final RevObject obj) throws TransportException {
 
 				switch (sType) {
 				case Constants.OBJ_BLOB:
-				case Constants.OBJ_TREE: {
-					final ObjectId sId = treeWalk.getObjectId(0);
-					needs(revWalk.lookupAny(sId, sType));
+				case Constants.OBJ_TREE:
+					treeWalk.getObjectId(idBuffer, 0);
+					needs(revWalk.lookupAny(idBuffer, sType));
 					continue;
-				}
+
 				default:
 					if (FileMode.GITLINK.equals(mode))
 						continue;
+					treeWalk.getObjectId(idBuffer, 0);
 					throw new CorruptObjectException("Invalid mode " + mode
-							+ " for " + treeWalk.getObjectId(0).name() + " "
+							+ " for " + idBuffer.name() + " "
 							+ treeWalk.getPathString() + " in "
 							+ obj.getId().name() + ".");
 				}
@@ -722,14 +726,14 @@ private void markTreeComplete(final RevTree tree) throws IOException {
 			final int sType = mode.getObjectType();
 
 			switch (sType) {
-			case Constants.OBJ_BLOB: {
-				final ObjectId sid = treeWalk.getObjectId(0);
-				revWalk.lookupAny(sid, sType).add(COMPLETE);
+			case Constants.OBJ_BLOB:
+				treeWalk.getObjectId(idBuffer, 0);
+				revWalk.lookupAny(idBuffer, sType).add(COMPLETE);
 				continue;
-			}
+
 			case Constants.OBJ_TREE: {
-				final ObjectId sid = treeWalk.getObjectId(0);
-				final RevObject o = revWalk.lookupAny(sid, sType);
+				treeWalk.getObjectId(idBuffer, 0);
+				final RevObject o = revWalk.lookupAny(idBuffer, sType);
 				if (!o.has(COMPLETE)) {
 					o.add(COMPLETE);
 					treeWalk.enterSubtree();
@@ -739,8 +743,9 @@ private void markTreeComplete(final RevTree tree) throws IOException {
 			default:
 				if (FileMode.GITLINK.equals(mode))
 					continue;
+				treeWalk.getObjectId(idBuffer, 0);
 				throw new CorruptObjectException("Invalid mode " + mode
-						+ " for " + treeWalk.getObjectId(0).name() + " "
+						+ " for " + idBuffer.name() + " "
 						+ treeWalk.getPathString() + " in " + tree.name() + ".");
 			}
 		}

-- 
1.6.1.rc4.301.g5497a
Previous: Shawn O. PearceNext: Shawn O. Pearce
Message 6 of 26 in “Misc. performance tweaks”
  1. 00/18 Misc. performance tweaksShawn O. Pearce, Dec 25, 2008
  2. 01/23 Improve hit performance on the UnpackedObjectCacheShawn O. Pearce, Dec 25, 2008
  3. 02/23 Add MutableObjectId.clear() to set the id to zeroIdShawn O. Pearce, Dec 25, 2008
  4. 03/23 Allow TreeWalk callers to pass a MutableObjectId to get the current idShawn O. Pearce, Dec 25, 2008
  5. 04/23 Switch ObjectWalk to use the new MutableObjectId form in TreeWalkShawn O. Pearce, Dec 25, 2008
  6. 05/23 Change walker based fetch to use TreeWalk's MutableObjectId accessorShawn O. Pearce, Dec 25, 2008
  7. 06/23 Reduce garbage allocation when using TreeWalkShawn O. Pearce, Dec 25, 2008
  8. 07/23 Switch ObjectWalk to use a naked CanonicalTreeParser because its fasterShawn O. Pearce, Dec 25, 2008
  9. 08/23 Remove the unused PackFile.get(ObjectId) formShawn O. Pearce, Dec 25, 2008
  10. 09/23 Remove getId from ObjectLoader API as its unnecessary overheadShawn O. Pearce, Dec 25, 2008
  11. 10/23 Make mmap mode more reliable by forcing GC at the correct spotShawn O. Pearce, Dec 25, 2008
  12. 11/23 Rewrite WindowCache to use a hash tableShawn O. Pearce, Dec 25, 2008
  13. 12/23 Change ByteArrayWindow to read content outside of WindowCache's lockShawn O. Pearce, Dec 25, 2008
  14. 13/23 Dispose of RevCommit buffers when they aren't used in PackWriterShawn O. Pearce, Dec 25, 2008
  15. 14/23 Don't unpack delta chains while writing a pack from a pack v1 indexShawn O. Pearce, Dec 25, 2008
  16. 15/23 Don't unpack delta chains while converting delta to whole objectShawn O. Pearce, Dec 25, 2008
  17. 16/23 Defer parsing of the ObjectId while walking a PackIndex IteratorShawn O. Pearce, Dec 25, 2008
  18. 17/23 Only do one getCachedBytes per whole object writtenShawn O. Pearce, Dec 25, 2008
  19. 18/23 Correctly use a long for the offsets within a generated packShawn O. Pearce, Dec 25, 2008
  20. 19/23 Allow more direct access to determine isWrittenShawn O. Pearce, Dec 25, 2008
  21. 20/23 Move "wantWrite" field of ObjectToPack into the flags fieldShawn O. Pearce, Dec 25, 2008
  22. 21/23 Use an ArrayList for the reuseLoader collection in PackWriterShawn O. Pearce, Dec 25, 2008
  23. 22/23 Don't cut off existing delta chains if we are reusing deltasShawn O. Pearce, Dec 25, 2008
  24. 23/23 Correctly honor the thin parameter to PackWriter.writePackShawn O. Pearce, Dec 25, 2008
  25. Robin RosenbergDec 27, 2008
  26. 11/23 Rewrite WindowCache to use a hash tableShawn O. Pearce, Dec 27, 2008

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