hadoop-mapreduce-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Jean-Daniel Cryans <jdcry...@apache.org>
Subject Client hanging 20 seconds after job's over (WAS: Re: Can I run HBase 0.20.6 on Hadoop 0.21?)
Date Mon, 27 Sep 2010 19:18:17 GMT
(adding mapreduce-user@ and re-scoping title)

Can you jstack the client while it's waiting 20 seconds? Is it still
waiting for the job to come back or it's something else? Is the job
itself done cleaning 20 seconds before the call returns on the client
side (check the web ui)?


On Mon, Sep 27, 2010 at 12:10 PM, Pete Tyler <peteralantyler@gmail.com> wrote:
> Thanks for the offer, much appreciated I have a very simple mapreduce job on a pseudo
distributed system. I have a very small amount of persisted data.
> Running locally the mapreduce job runs very quickly, less than three seconds.
> When I run the job against the pseudo distributed hadoop, still on the same machine,
as the client then I see the following,
> - the map and reduce classes run very quickly, a matter of mills in total ... sweet
> - the client, blocks waiting for the job to finish for about 20 seconds ... very slow
> I'm trying to understand why I have this 20 second overhead and what I can do about it.
> My map and reduce classes are in my Hadoop classpath.
> On Sep 27, 2010, at 11:32 AM, Jean-Daniel Cryans <jdcryans@apache.org> wrote:
>> Using 0.21.0 may reveal newer bugs rather than fixing your older ones.
>> Maybe we can help you debugging 0.20.2, what are you seeing?
>> J-D

View raw message