HTable is explicitly not thread-safe when using the write buffer.
> -----Original Message----- > From: Ryan Rawson [mailto:[email protected]] > Sent: Thursday, June 10, 2010 2:34 PM > To: [email protected] > Cc: hbase-user > Subject: Re: dead-lock at HTable flusCommits with multiple clients... > > I'd would need to see more of jstack to feel comfortable on calling > this a deadlock... However, HTable is not designed to be used by > multiple threads. Each thread should have it's own copy of HTable. > > -ryan > > On Thu, Jun 10, 2010 at 2:26 PM, Sujee Maniyam <[email protected]> wrote: > > I am importing data into Hbase with a client running 10 threads. I > > explicitly call 'flushCommit' from each thread (after a few thousand > puts) > > > > Here is the thread-dump: > > > > "pool-1-thread-20" prio=10 tid=0x0000000041072800 nid=0x17d8 in > > Object.wait() [0x00007fdaee6c8000] > > java.lang.Thread.State: WAITING (on object monitor) > > at java.lang.Object.wait(Native Method) > > at java.lang.Object.wait(Object.java:485) > > at > > org.apache.hadoop.hbase.ipc.HBaseClient.call(HBaseClient.java:721) > > - locked <0x00007fdb26342780> (a > > org.apache.hadoop.hbase.ipc.HBaseClient$Call) > > at > > > org.apache.hadoop.hbase.ipc.HBaseRPC$Invoker.invoke(HBaseRPC.java:333) > > at $Proxy0.put(Unknown Source) > > at > > > org.apache.hadoop.hbase.client.HConnectionManager$TableServers$3$1.call > (HConnectionManager.java:1243) > > at > > > org.apache.hadoop.hbase.client.HConnectionManager$TableServers$3$1.call > (HConnectionManager.java:1241) > > at > > > org.apache.hadoop.hbase.client.HConnectionManager$TableServers.getRegio > nServerWithRetries(HConnectionManager.java:1050) > > at > > > org.apache.hadoop.hbase.client.HConnectionManager$TableServers$3.doCall > (HConnectionManager.java:1240) > > at > > > org.apache.hadoop.hbase.client.HConnectionManager$TableServers$Batch.pr > ocess(HConnectionManager.java:1162) > > at > > > org.apache.hadoop.hbase.client.HConnectionManager$TableServers.processB > atchOfRows(HConnectionManager.java:1248) > > at > > org.apache.hadoop.hbase.client.HTable.flushCommits(HTable.java:666) > > at org.apache.hadoop.hbase.client.HTable.put(HTable.java:510) > > - locked <0x00007fdafc35da30> (a > > org.apache.hadoop.hbase.client.HTable) > > > > "pool-1-thread-19" prio=10 tid=0x000000004100c800 nid=0x17cd in > > Object.wait() [0x00007fdaee7c9000] > > java.lang.Thread.State: WAITING (on object monitor) > > at java.lang.Object.wait(Native Method) > > at java.lang.Object.wait(Object.java:485) > > at > > org.apache.hadoop.hbase.ipc.HBaseClient.call(HBaseClient.java:721) > > - locked <0x00007fdb25b487c0> (a > > org.apache.hadoop.hbase.ipc.HBaseClient$Call) > > at > > > org.apache.hadoop.hbase.ipc.HBaseRPC$Invoker.invoke(HBaseRPC.java:333) > > at $Proxy0.put(Unknown Source) > > at > > > org.apache.hadoop.hbase.client.HConnectionManager$TableServers$3$1.call > (HConnectionManager.java:1243) > > at > > > org.apache.hadoop.hbase.client.HConnectionManager$TableServers$3$1.call > (HConnectionManager.java:1241) > > at > > > org.apache.hadoop.hbase.client.HConnectionManager$TableServers.getRegio > nServerWithRetries(HConnectionManager.java:1050) > > at > > > org.apache.hadoop.hbase.client.HConnectionManager$TableServers$3.doCall > (HConnectionManager.java:1240) > > at > > > org.apache.hadoop.hbase.client.HConnectionManager$TableServers$Batch.pr > ocess(HConnectionManager.java:1162) > > at > > > org.apache.hadoop.hbase.client.HConnectionManager$TableServers.processB > atchOfRows(HConnectionManager.java:1248) > > at > > org.apache.hadoop.hbase.client.HTable.flushCommits(HTable.java:666) > > at org.apache.hadoop.hbase.client.HTable.put(HTable.java:510) > > - locked <0x00007fdafc69d290> (a > > org.apache.hadoop.hbase.client.HTable) > > > > > > and so on... > > > > Is this is a known issue? otherwise I can open a ticket. > > > > thanks > > Sujee > > > > http://sujee.net > >
