hbase-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Jean-Daniel Cryans (JIRA)" <j...@apache.org>
Subject [jira] Created: (HBASE-2909) SoftValueSortedMap is broken, can generate NPEs
Date Wed, 11 Aug 2010 21:07:18 GMT
SoftValueSortedMap is broken, can generate NPEs
-----------------------------------------------

                 Key: HBASE-2909
                 URL: https://issues.apache.org/jira/browse/HBASE-2909
             Project: HBase
          Issue Type: Bug
          Components: client
    Affects Versions: 0.89.20100621, 0.20.6
            Reporter: Jean-Daniel Cryans
            Priority: Blocker
             Fix For: 0.20.7, 0.90.0


The way SoftValueSortedMap is using SoftValues, it looks like that it's able to get it's keys
garbage collected along with the values themselves. We got this issue in production but I
was also able to randomly generate it using YCSB with 300 threads. Here's an example on 0.20
with jdk 1.6u14:

{noformat}

java.lang.NullPointerException
        at org.apache.hadoop.hbase.util.Bytes.compareTo(Bytes.java:1036)
        at org.apache.hadoop.hbase.util.Bytes$ByteArrayComparator.compare(Bytes.java:104)
        at org.apache.hadoop.hbase.util.Bytes$ByteArrayComparator.compare(Bytes.java:96)
        at java.util.TreeMap.cmp(TreeMap.java:1911)
        at java.util.TreeMap.get(TreeMap.java:1835)
        at org.apache.hadoop.hbase.util.SoftValueSortedMap.get(SoftValueSortedMap.java:91)
        at org.apache.hadoop.hbase.client.HConnectionManager$TableServers.getCachedLocation(HConnectionManager.java:788)
        at org.apache.hadoop.hbase.client.HConnectionManager$TableServers.locateRegionInMeta(HConnectionManager.java:651)
        at org.apache.hadoop.hbase.client.HConnectionManager$TableServers.locateRegion(HConnectionManager.java:634)
        at org.apache.hadoop.hbase.client.HConnectionManager$TableServers.locateRegion(HConnectionManager.java:601)
        at org.apache.hadoop.hbase.client.HTable.<init>(HTable.java:128)
        at org.apache.hadoop.hbase.thrift.ThriftServer$HBaseHandler.getTable(ThriftServer.java:262)
        at org.apache.hadoop.hbase.thrift.ThriftServer$HBaseHandler.mutateRowTs(ThriftServer.java:585)
        at org.apache.hadoop.hbase.thrift.ThriftServer$HBaseHandler.mutateRow(ThriftServer.java:578)
        at org.apache.hadoop.hbase.thrift.generated.Hbase$Processor$mutateRow.process(Hbase.java:2345)
        at org.apache.hadoop.hbase.thrift.generated.Hbase$Processor.process(Hbase.java:1988)
        at org.apache.thrift.server.TThreadPoolServer$WorkerProcess.run(TThreadPoolServer.java:259)
        at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
        at java.lang.Thread.run(Thread.java:619)
{noformat}

In this specific case, the null cannot be the passed key because it's coming from HTable which
uses HConstants.EMPTY_START_ROW. It cannot be a null key that was inserted previously because
we would have got the NPE at insert time. This can only mean that some key *became* null.

-- 
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.


Mime
View raw message