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HBase >> mail # user >> Hbase CopyTable timeout on scanner

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Re: Hbase CopyTable timeout on scanner

One thing you might want to watch out for is that if you are starting with
421 regions on the source but the dest table isn't pre-split then it's
going to try to slam all the data into one region and then have to split
(and split and split, etc.).


On 5/7/12 8:22 AM, "Damien HARDY" <[EMAIL PROTECTED]> wrote:

>I try to copy a table from on cluster to another.
>source is a 2 nodes cluster 16cpu / 32GoRAM (hadoop001, hadoop002).
>destination is a 3 nodes cluster 16cpu /64GoRAM (hbase01, hbase02,
>nodes are all implementing datanode, regionserver,masterserver and
>zookeeper of CDH3u3
>region size is 2G on source and 4G on destination
>Max Heap is 8G on region server
>There is 421 regions on source (80% is empty because of TTL and time
>based rowkey)
>about 400k rows of syslogs (1 or 2ko).
>My problem is that when I performe au MR job with
>hbase org.apache.hadoop.hbase.mapreduce.CopyTable
>--peer.adr=hbase01,hbase02,hbase04:2181:/hbase <table>
>on the source cluster. Nodes seems not doing so much (load average is
>low) and load on regionservers is unconstant (going from 0 to 60k
>request/sec with bursts)
>12/05/07 12:08:17 INFO mapred.JobClient: Task Id :
>attempt_201204241409_0005_m_000343_0, Status : FAILED
>org.apache.hadoop.hbase.client.ScannerTimeoutException: 184008ms passed
>since the last invocation, timeout is currently set to 120000
>    at
>    at
>    at
>    at
>    at
>    at org.apache.hadoop.mapreduce.Mapper.run(Mapper.java:143)
>    at org.apache.hadoop.mapred.MapTask.runNewMapper(MapTask.java:647)
>    at org.apache.hadoop.mapred.MapTask.run(MapTask.java:323)
>    at org.apache.hadoop.mapred.Child$4.run(Child.java:270)
>    at java.security.AccessController.doPrivileged(Native Method)
>    at javax.security.auth.Subject.doAs(Subject.java:396)
>    at
>After some retries the tasks seems to succeed but it's very long.
>parameters that I tryied to change on submiting job:
>hbase.client.scanner.caching is 2000
>hbase.regionserver.lease.period is 120000
>What other parameters could be helpfull to maximise the use of the
>cluster resources for this simple copy.
>I can't see where is bootleneck.
>Thank you.