[HBASE-5702] MasterSchemaChangeTracker.excludeRegionServerForSchemaChanges leaks a MonitoredTask per call

• Type: Bug
• Status: Closed
• Priority: Critical
• Resolution: Not A Problem
• Affects Version/s: 0.94.0
• Assignee: Unassigned
• Reporter: Jean-Daniel Cryans
• Created: 02/Apr/12 22:22
• Updated: 13/Jun/22 16:02
• Resolved: 11/Apr/15 01:24

Description

This bug is so easy to reproduce I'm wondering why it hasn't been reported yet. Stop any number of region servers on a 0.94/6 cluster and you'll see in the master interface one task per stopped region server saying the following:

Processing schema change exclusion for region server = sv4r27s44,62023,1333402175340

RUNNING (since 5sec ago)

No schema change in progress. Skipping exclusion for server = sv4r27s44,62023,1333402175340 (since 5sec ago)

It's gonna stay there until the master cleans it:

WARN org.apache.hadoop.hbase.monitoring.TaskMonitor: Status Processing schema change exclusion for region server = sv4r27s44,62023,1333402175340: status=No schema change in progress. Skipping exclusion for server = sv4r27s44,62023,1333402175340, state=RUNNING, startTime=1333404636419, completionTime=-1 appears to have been leaked

It's not clear to me why it's using a MonitoredTask in the first place.

Issue Links

• is related to: HBASE-5715 Revert 'Instant schema alter' for now, HBASE-4213