[ROCKETMQ-45] Delete consume queue hang file

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 4.1.0-incubating
• Fix Version/s: 4.0.0-incubating
• Component/s: rocketmq-store
• Assignee: Xinyu Zhou
• Reporter: Zhanhui Li
• Created: 12/Jan/17 06:41
• Updated: 23/Jan/17 09:25
• Resolved: 23/Jan/17 09:10

Description

Consume queue file may hang and stop further deleting under concurrent scenario.

If the consume queue file is concurrently held by another thread, mappedFile.destroy(interval) will only set firstShutdownTimestamp to current timestamp and available false, then return false directly.
Check MappedFileQueue.java#deleteExpiredFileByOffset,

if (destroy && mappedFile.destroy(1000 * 60)) {
files.add(mappedFile);
deleteCount++;
} else {
break;
}
the current round of deletion will be stopped and current mapped file becomes handed.

Next time trying to delete mapped file of this mapped file queue, MappedFileQueue.java#deleteExpiredFileByOffset(offset, unitSize) line No.390
MappedFile mappedFile = (MappedFile) mfs[i];
SelectMappedBufferResult result = mappedFile.selectMappedBuffer(this.mappedFileSize - unitSize);
will always return null as the mapped file is no longer available and cannot hold. Current implementation will only log a warn and exit.

Issue Links

• links to: GitHub Pull Request #39