RepoCommand: Retry commit on LockFailure
When the target repository is receiving commits from other sources,
the repo command commit can fail with a LOCK_FAILURE. We could let
callers retry, but then the command needs to redo all the work (opening
all subrepos to recreate the tree).
Retry the commit in LOCK_FAILURE inside the command. The commit
rewrites the whole tree, so it shouldn't have merge errors. Use an
exponential delay with jitter for the retries.
Change-Id: I517b6f2afd16a4b695e6cf471b5d6cf492024ec4
Signed-off-by: Ivan Frade <ifrade@google.com>
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/gitrepo/RepoCommand.java b/org.eclipse.jgit/src/org/eclipse/jgit/gitrepo/RepoCommand.java
index 5bf95de..552315d 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/gitrepo/RepoCommand.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/gitrepo/RepoCommand.java
@@ -80,6 +80,13 @@
* @since 3.4
*/
public class RepoCommand extends GitCommand<RevCommit> {
+ private static final int LOCK_FAILURE_MAX_RETRIES = 5;
+
+ // Retry exponentially with delays in this range
+ private static final int LOCK_FAILURE_MIN_RETRY_DELAY_MILLIS = 50;
+
+ private static final int LOCK_FAILURE_MAX_RETRY_DELAY_MILLIS = 5000;
+
private String manifestPath;
private String baseUri;
private URI targetUri;
@@ -686,50 +693,22 @@
builder.finish();
ObjectId treeId = index.writeTree(inserter);
- // Create a Commit object, populate it and write it
- ObjectId headId = repo.resolve(targetBranch + "^{commit}"); //$NON-NLS-1$
- if (headId != null && rw.parseCommit(headId).getTree().getId().equals(treeId)) {
- // No change. Do nothing.
- return rw.parseCommit(headId);
+ long prevDelay = 0;
+ for (int i = 0; i < LOCK_FAILURE_MAX_RETRIES - 1; i++) {
+ try {
+ return commitTreeOnCurrentTip(
+ inserter, rw, treeId);
+ } catch (ConcurrentRefUpdateException e) {
+ prevDelay = FileUtils.delay(prevDelay,
+ LOCK_FAILURE_MIN_RETRY_DELAY_MILLIS,
+ LOCK_FAILURE_MAX_RETRY_DELAY_MILLIS);
+ Thread.sleep(prevDelay);
+ repo.getRefDatabase().refresh();
+ }
}
-
- CommitBuilder commit = new CommitBuilder();
- commit.setTreeId(treeId);
- if (headId != null)
- commit.setParentIds(headId);
- commit.setAuthor(author);
- commit.setCommitter(author);
- commit.setMessage(RepoText.get().repoCommitMessage);
-
- ObjectId commitId = inserter.insert(commit);
- inserter.flush();
-
- RefUpdate ru = repo.updateRef(targetBranch);
- ru.setNewObjectId(commitId);
- ru.setExpectedOldObjectId(headId != null ? headId : ObjectId.zeroId());
- Result rc = ru.update(rw);
-
- switch (rc) {
- case NEW:
- case FORCED:
- case FAST_FORWARD:
- // Successful. Do nothing.
- break;
- case REJECTED:
- case LOCK_FAILURE:
- throw new ConcurrentRefUpdateException(
- MessageFormat.format(
- JGitText.get().cannotLock, targetBranch),
- ru.getRef(),
- rc);
- default:
- throw new JGitInternalException(MessageFormat.format(
- JGitText.get().updatingRefFailed,
- targetBranch, commitId.name(), rc));
- }
-
- return rw.parseCommit(commitId);
- } catch (GitAPIException | IOException e) {
+ // In the last try, just propagate the exceptions
+ return commitTreeOnCurrentTip(inserter, rw, treeId);
+ } catch (GitAPIException | IOException | InterruptedException e) {
throw new ManifestErrorException(e);
}
}
@@ -746,6 +725,51 @@
}
}
+
+ private RevCommit commitTreeOnCurrentTip(ObjectInserter inserter,
+ RevWalk rw, ObjectId treeId)
+ throws IOException, ConcurrentRefUpdateException {
+ ObjectId headId = repo.resolve(targetBranch + "^{commit}"); //$NON-NLS-1$
+ if (headId != null && rw.parseCommit(headId).getTree().getId().equals(treeId)) {
+ // No change. Do nothing.
+ return rw.parseCommit(headId);
+ }
+
+ CommitBuilder commit = new CommitBuilder();
+ commit.setTreeId(treeId);
+ if (headId != null)
+ commit.setParentIds(headId);
+ commit.setAuthor(author);
+ commit.setCommitter(author);
+ commit.setMessage(RepoText.get().repoCommitMessage);
+
+ ObjectId commitId = inserter.insert(commit);
+ inserter.flush();
+
+ RefUpdate ru = repo.updateRef(targetBranch);
+ ru.setNewObjectId(commitId);
+ ru.setExpectedOldObjectId(headId != null ? headId : ObjectId.zeroId());
+ Result rc = ru.update(rw);
+ switch (rc) {
+ case NEW:
+ case FORCED:
+ case FAST_FORWARD:
+ // Successful. Do nothing.
+ break;
+ case REJECTED:
+ case LOCK_FAILURE:
+ throw new ConcurrentRefUpdateException(MessageFormat
+ .format(JGitText.get().cannotLock, targetBranch),
+ ru.getRef(), rc);
+ default:
+ throw new JGitInternalException(MessageFormat.format(
+ JGitText.get().updatingRefFailed,
+ targetBranch, commitId.name(), rc));
+ }
+
+ return rw.parseCommit(commitId);
+ }
+
private void addSubmodule(String name, String url, String path,
String revision, List<CopyFile> copyfiles, List<LinkFile> linkfiles,
Git git) throws GitAPIException, IOException {
