2 files changed, 44 insertions, 28 deletions

diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/pack/DeltaTask.java b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/pack/DeltaTask.java
index 218696eef6..cc212fb818 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/pack/DeltaTask.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/pack/DeltaTask.java
@@ -76,23 +76,24 @@ final class DeltaTask implements Callable<Object> {
 		}
 
 		synchronized Slice stealWork() {
-			for (int attempts = 0; attempts < 2; attempts++) {
+			for (;;) {
 				DeltaTask maxTask = null;
+				Slice maxSlice = null;
 				int maxWork = 0;
+
 				for (DeltaTask task : tasks) {
-					int r = task.remaining();
-					if (maxWork < r) {
+					Slice s = task.remaining();
+					if (s != null && maxWork < s.size()) {
 						maxTask = task;
-						maxWork = r;
+						maxSlice = s;
+						maxWork = s.size();
 					}
 				}
 				if (maxTask == null)
 					return null;
-				Slice s = maxTask.stealWork();
-				if (s != null)
-					return s;
+				if (maxTask.tryStealWork(maxSlice))
+					return maxSlice;
 			}
-			return null;
 		}
 	}
 
@@ -104,6 +105,10 @@ final class DeltaTask implements Callable<Object> {
 			beginIndex = b;
 			endIndex = e;
 		}
+
+		final int size() {
+			return endIndex - beginIndex;
+		}
 	}
 
 	private final Block block;
@@ -131,13 +136,13 @@ final class DeltaTask implements Callable<Object> {
 		return null;
 	}
 
-	int remaining() {
+	Slice remaining() {
 		DeltaWindow d = dw;
-		return d != null ? d.remaining() : 0;
+		return d != null ? d.remaining() : null;
 	}
 
-	Slice stealWork() {
+	boolean tryStealWork(Slice s) {
 		DeltaWindow d = dw;
-		return d != null ? d.stealWork() : null;
+		return d != null ? d.tryStealWork(s) : false;
 	}
 }
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/pack/DeltaWindow.java b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/pack/DeltaWindow.java
index 2eb1daf748..7688da395b 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/pack/DeltaWindow.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/pack/DeltaWindow.java
@@ -115,26 +115,37 @@ final class DeltaWindow {
 		res = DeltaWindowEntry.createWindow(config.getDeltaSearchWindowSize());
 	}
 
-	synchronized int remaining() {
-		return end - cur;
-	}
-
-	synchronized DeltaTask.Slice stealWork() {
+	synchronized DeltaTask.Slice remaining() {
 		int e = end;
-		int n = (e - cur) >>> 1;
-		if (0 == n)
+		int halfRemaining = (e - cur) >>> 1;
+		if (0 == halfRemaining)
 			return null;
 
-		int t = e - n;
-		int h = toSearch[t].getPathHash();
-		while (cur < t) {
-			if (h == toSearch[t - 1].getPathHash())
-				t--;
-			else
-				break;
+		int split = e - halfRemaining;
+		int h = toSearch[split].getPathHash();
+
+		// Attempt to split on the next path after the 50% split point.
+		for (int n = split + 1; n < e; n++) {
+			if (h != toSearch[n].getPathHash())
+				return new DeltaTask.Slice(n, e);
 		}
-		end = t;
-		return new DeltaTask.Slice(t, e);
+
+		if (h != toSearch[cur].getPathHash()) {
+			// Try to split on the path before the 50% split point.
+			// Do not split the path currently being processed.
+			for (int p = split - 1; cur < p; p--) {
+				if (h != toSearch[p].getPathHash())
+					return new DeltaTask.Slice(p + 1, e);
+			}
+		}
+		return null;
+	}
+
+	synchronized boolean tryStealWork(DeltaTask.Slice s) {
+		if (s.beginIndex <= cur)
+			return false;
+		end = s.beginIndex;
+		return true;
 	}
 
 	void search() throws IOException {