Have you also increased the maximum number of processes ("nproc" in the same
file)? I have definitely seen this kind of error as a result of in
insufficiently large process limit.
Some more details, maybe, on these pages:
http://ww2.cs.fsu.edu/~czhang/errors.html
http://incubator.apache.org/ambari/1.2.0/installing-hadoop-using-ambari/content/ambari-chap5-3-1.html
-Krishmin
On Mar 12, 2013, at 1:52 PM, Mike Hugo wrote:
> Eventually it will be 4 nodes, this particular test was running on a single
> node
>
> hadoop version is 1.0.4
>
> we already upped the limits in /etc/security/limits.conf to:
>
> usernamehere hard nofile 16384
>
> Mike
>
>
> On Tue, Mar 12, 2013 at 12:49 PM, Krishmin Rai <[email protected]> wrote:
> Hi Mike,
> This could be related to the maximum number of processes or files allowed
> for your linux user. You might try bumping these values up (e.g via
> /etc/security/limits.conf).
>
> -Krishmin
>
> On Mar 12, 2013, at 1:35 PM, Mike Hugo wrote:
>
> > Hello,
> >
> > I'm setting up accumulo on a small cluster where each node has 96GB of ram
> > and 24 cores. Any recommendations on what memory settings to use for the
> > accumulo processes, as well as what to use for the hadoop processes (e.g.
> > datanode, etc)?
> >
> > I did a small test just to try some things standalone on a single node,
> > setting the accumulo processes to 2GB of ram and the HADOOP_HEAPSIZE=2000.
> > While running a map reduce job with 4 workers (each allocated 1GB of RAM),
> > the datanode runs out of memory about 25% of the way into the job and dies.
> > The job is basically building an index, iterating over data in one table
> > and applying mutations to another - nothing too fancy.
> >
> > Since I'm dealing with a subset of data, I set the table split threshold to
> > 128M for testing purposes, there are currently about 170 tablets so we not
> > dealing with a ton of data here. Might this low split threshold be a
> > contributing factor?
> >
> > Should I increase the HADDOP_HEAPSIZE even further? Or will that just
> > delay the inevitable OOM error?
> >
> > The exception we are seeing is below.
> >
> > ERROR org.apache.hadoop.hdfs.server.datanode.DataNode:
> > DatanodeRegistration(...):DataXceiveServer: Exiting due
> > to:java.lang.OutOfMemoryError: unable to create new native thread
> > at java.lang.Thread.start0(Native Method)
> > at java.lang.Thread.start(Unknown Source)
> > at
> > org.apache.hadoop.hdfs.server.datanode.DataXceiverServer.run(DataXceiverServer.java:133)
> > at java.lang.Thread.run(Unknown Source)
> >
> >
> > Thanks for your help!
> >
> > Mike
>
>