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  1. HBase
  2. HBASE-22902

At regionserver start there's a request to roll the WAL



    • Bug
    • Status: Resolved
    • Minor
    • Resolution: Fixed
    • 3.0.0-alpha-1, 1.5.0, 2.3.0
    • 1.5.0
    • wal
    • None
    • Reviewed


      See HBASE-22301 for logic that requests to roll the WAL if regionserver encounters a slow write pipeline. In the logs, during regionserver start, I see that the WAL is requested to roll once. It's strange that we roll the WAL because it wasn't a slow sync. It appears when this code executes, we haven't initialized the rollOnSyncNs variable to use for determining whether it's a slow sync. Current pipeline also shows empty in the logs.

      Disclaimer: I'm experiencing this after backporting this to 1.3.x and building it there - I haven't attempted in 1.5.x, though I'd expect similar results.

      Regionserver logs follow (notice threshold=0 ms, current pipeline: []):

      Tue Aug 20 23:29:50 GMT 2019 Starting regionserver
      2019-08-20 23:29:57,824 INFO  wal.FSHLog - WAL configuration: blocksize=256 MB, rollsize=243.20 MB, prefix=[truncated]%2C1566343792434, suffix=, logDir=hdfs://[truncated]/hbase/WALs/[truncated],1566343792434, archiveDir=hdfs://[truncated]/hbase/oldWALs
      2019-08-20 23:29:58,104 INFO  wal.FSHLog - Slow sync cost: 186 ms, current pipeline: []
      2019-08-20 23:29:58,104 WARN  wal.FSHLog - Requesting log roll because we exceeded slow sync threshold; time=186 ms, threshold=0 ms, current pipeline: []
      2019-08-20 23:29:58,107 DEBUG regionserver.ReplicationSourceManager - Start tracking logs for wal group [truncated]%2C1566343792434 for peer 1
      2019-08-20 23:29:58,107 INFO  wal.FSHLog - New WAL /hbase/WALs/[truncated],1566343792434/[truncated]%2C1566343792434.1566343797824
      2019-08-20 23:29:58,109 DEBUG regionserver.ReplicationSource - Starting up worker for wal group [truncated]%2C1566343792434


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              sandeep.pal Sandeep Pal
              dmanning David Manning
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