[HBASE-4853] HBASE-4789 does overzealous pruning of seqids

• Type: Bug
• Status: Closed
• Priority: Critical
• Resolution: Fixed
• Fix Version/s: 0.92.0, 0.94.0
• Hadoop Flags: Reviewed
• Assignee: Michael Stack
• Reporter: Michael Stack
• Created: 22/Nov/11 23:53
• Updated: 12/Oct/12 05:34
• Resolved: 30/Nov/11 19:09

Description

Working w/ J-D on failing replication test turned up hole in seqids made by the patch over in hbase-4789. With this patch in place we see lots of instances of the suspicious: 'Last sequenceid written is empty. Deleting all old hlogs'

At a minimum, these lines need removing:

diff --git a/src/main/java/org/apache/hadoop/hbase/regionserver/wal/HLog.java b/src/main/java/org/apache/hadoop/hbase/regionserver/wal/HLog.java
index 623edbe..a0bbe01 100644
--- a/src/main/java/org/apache/hadoop/hbase/regionserver/wal/HLog.java
+++ b/src/main/java/org/apache/hadoop/hbase/regionserver/wal/HLog.java
@@ -1359,11 +1359,6 @@ public class HLog implements Syncable {
       // Cleaning up of lastSeqWritten is in the finally clause because we
       // don't want to confuse getOldestOutstandingSeqNum()
       this.lastSeqWritten.remove(getSnapshotName(encodedRegionName));
-      Long l = this.lastSeqWritten.remove(encodedRegionName);
-      if (l != null) {
-        LOG.warn("Why is there a raw encodedRegionName in lastSeqWritten? name=" +
-          Bytes.toString(encodedRegionName) + ", seqid=" + l);
-       }
       this.cacheFlushLock.unlock();
     }
   }

... but above is no good w/o figuring why WALs are not being rotated off.