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Re: Memory config for Hadoop cluster
Hi,

>
> I'm not using any scheduler.. Dont have multiple jobs running at the same
> time on the cluster.

That probably means you are using the default scheduler. Please note
that the default scheduler does not have the ability to schedule tasks
intelligently using the memory configuration parameters you specify.
Could you tell us what you'd like to achieve ?

The documentation here: http://bit.ly/cCbAab (and the link it has to
similar documentation in the Cluster Setup guide) will probably shed
more light on how the parameters should be used. Note that this is in
Hadoop 0.21, and the names of the parameters are different, though you
can see the correspondence with similar variables in Hadoop 0.20.

Thanks
Hemanth
>
> -Amandeep
>
> On Fri, Nov 5, 2010 at 12:21 AM, Hemanth Yamijala <[EMAIL PROTECTED]>wrote:
>
>> Amadeep,
>>
>> Which scheduler are you using ?
>>
>> Thanks
>> hemanth
>>
>> On Tue, Nov 2, 2010 at 2:44 AM, Amandeep Khurana <[EMAIL PROTECTED]> wrote:
>> > How are the following configs supposed to be used?
>> >
>> > mapred.cluster.map.memory.mb
>> > mapred.cluster.reduce.memory.mb
>> > mapred.cluster.max.map.memory.mb
>> > mapred.cluster.max.reduce.memory.mb
>> > mapred.job.map.memory.mb
>> > mapred.job.reduce.memory.mb
>> >
>> > These were included in 0.20 in HADOOP-5881.
>> >
>> > Now, here's what I'm setting only the following out of the above in my
>> > mapred-site.xml:
>> >
>> > mapred.cluster.map.memory.mb=896
>> > mapred.cluster.reduce.memory.mb=1024
>> >
>> > When I run job, I get the following error:
>> >
>> >
>> > TaskTree [pid=1958,tipID=attempt_201011012101_0001_m_000000_0] is
>> > running beyond memory-limits. Current usage : 1358553088bytes. Limit :
>> > -1048576bytes. Killing task.
>> >
>> > I'm not sure how it got the Limit as -1048576bytes... Also, what are the
>> > cluster.max params supposed to be set as? Are they the max on the entire
>> > cluster or on a particular node?
>> >
>> > -Amandeep
>> >
>>
>