[HBASE-1352] incrementColumnValue/Memcache bug

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 0.19.1
• Fix Version/s: 0.19.2
• Component/s: regionserver

Environment

Ubuntu 8.10

• Assignee: Unassigned
• Reporter: atppp
• Created: 27/Apr/09 22:36
• Updated: 13/Sep/09 22:31
• Resolved: 03/May/09 21:27

Description

When I do a large amount of incrementColumnValue(), I got NullPointerException thrown from Memcache.java:

2009-04-27 14:59:03,620 INFO org.apache.hadoop.ipc.HBaseServer: IPC Server handler 1 on 59710, call incrementColumnValue([B@1317bfb, [B@1c2a074, [B@b427c1, 1) from 127.0.0.1:52296: error: java.io.IOException: java.lang.NullPointerException
java.io.IOException: java.lang.NullPointerException
at org.apache.hadoop.hbase.regionserver.Memcache.get(Memcache.java:609)
at org.apache.hadoop.hbase.regionserver.Memcache.get(Memcache.java:244)
at org.apache.hadoop.hbase.regionserver.Memcache.get(Memcache.java:226)
at org.apache.hadoop.hbase.regionserver.HRegion.incrementColumnValue(HRegion.java:2636)
at org.apache.hadoop.hbase.regionserver.HRegionServer.incrementColumnValue(HRegionServer.java:2299)
at sun.reflect.GeneratedMethodAccessor13.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.apache.hadoop.hbase.ipc.HBaseRPC$Server.call(HBaseRPC.java:632)
at org.apache.hadoop.hbase.ipc.HBaseServer$Handler.run(HBaseServer.java:912)
(called from thrift interface)

I consistently hit this exception after restarting Hbase (exactly the same location in my code)

Quick fix is (with HBASE-1319.patch applied) at Memcache.java:609, say if (deletes != null) deletes.add(itKey);

but probably better to change Memcache.java:226. Also the trunk already changed the StoreKey format and doesn't have this bug.