We are running Gerrit 2.11.4 and have recently had a problem in that Gerrit couldn't read one of our repositories making it totally unusable. We tried running flush-caches --all but that did not fix the problem. The only way we were able to fix it was to do a Gerrit restart. I was wondering if anybody else has run into this issue or might know why this would be happening?
[2016-03-27 05:41:19,448] WARN org.eclipse.jgit.internal.storage.file.ObjectDirectory : Pack file /home/gerrit2/review_site/git/openstack/ec2-api.git/objects/pack/pack-3a686787179a5e70d4c53e9be6897ec5ed0821b2.pack was deleted, removing it from pack list
[2016-03-27 05:41:19,450] WARN com.google.gerrit.server.project.ProjectCacheImpl : Cannot read project openstack/ec2-api
java.util.concurrent.ExecutionException: org.eclipse.jgit.errors.MissingObjectException: Missing unknown 72803eb8013ff25d7751b4a7c6cd6571d6631435
at com.google.common.util.concurrent.AbstractFuture$Sync.getValue(AbstractFuture.java:299)
at com.google.common.util.concurrent.AbstractFuture$Sync.get(AbstractFuture.java:286)
at com.google.common.util.concurrent.AbstractFuture.get(AbstractFuture.java:116)
at com.google.common.util.concurrent.Uninterruptibles.getUninterruptibly(Uninterruptibles.java:137)
at com.google.common.cache.LocalCache$Segment.getAndRecordStats(LocalCache.java:2348)
at com.google.common.cache.LocalCache$Segment.loadSync(LocalCache.java:2320)
at com.google.common.cache.LocalCache$Segment.lockedGetOrLoad(LocalCache.java:2282)
at com.google.common.cache.LocalCache$Segment.get(LocalCache.java:2197)
at com.google.common.cache.LocalCache.get(LocalCache.java:3937)
at com.google.common.cache.LocalCache.getOrLoad(LocalCache.java:3941)
at com.google.common.cache.LocalCache$LocalLoadingCache.get(LocalCache.java:4824)
at com.google.gerrit.server.project.ProjectCacheImpl.checkedGet(ProjectCacheImpl.java:141)
at com.google.gerrit.server.project.ProjectCacheImpl.get(ProjectCacheImpl.java:128)
at com.google.gerrit.server.project.ListProjects.display(ListProjects.java:268)
at com.google.gerrit.sshd.commands.ListProjectsCommand.run(ListProjectsCommand.java:43)
at com.google.gerrit.sshd.SshCommand$1.run(SshCommand.java:35)
at com.google.gerrit.sshd.BaseCommand$TaskThunk.run(BaseCommand.java:445)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471)
at java.util.concurrent.FutureTask.run(FutureTask.java:262)
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$201(ScheduledThreadPoolExecutor.java:178)
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:292)
at com.google.gerrit.server.git.WorkQueue$Task.run(WorkQueue.java:379)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at java.lang.Thread.run(Thread.java:745)
Caused by: org.eclipse.jgit.errors.MissingObjectException: Missing unknown 72803eb8013ff25d7751b4a7c6cd6571d6631435
at org.eclipse.jgit.internal.storage.file.WindowCursor.open(WindowCursor.java:145)
at org.eclipse.jgit.lib.ObjectReader.open(ObjectReader.java:226)
at org.eclipse.jgit.revwalk.RevWalk.parseAny(RevWalk.java:859)
at org.eclipse.jgit.revwalk.RevWalk.parseCommit(RevWalk.java:772)
at com.google.gerrit.server.git.VersionedMetaData.load(VersionedMetaData.java:123)
at com.google.gerrit.server.git.VersionedMetaData.load(VersionedMetaData.java:100)
at com.google.gerrit.server.project.ProjectCacheImpl$Loader.load(ProjectCacheImpl.java:294)
at com.google.gerrit.server.project.ProjectCacheImpl$Loader.load(ProjectCacheImpl.java:278)
at com.google.common.cache.LocalCache$LoadingValueReference.loadFuture(LocalCache.java:3527)
at com.google.common.cache.LocalCache$Segment.loadSync(LocalCache.java:2319)
... 19 more