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MapReduce >> mail # user >> Memory based scheduling

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Re: Memory based scheduling
Not true, take a look at my prev. response.

On Oct 30, 2012, at 9:08 AM, lohit wrote:

> As far as I recall this is not possible. Per job or per user configurations like these are little difficult in existing version.
> What you could try is to set max map per job to be say half of cluster capacity. (This is possible with FairSchedule, I do not know of CapacityScheduler)
> For eg, if you have 10 nodes with 4 slots each. You would create pool and set max maps to be 20.
> JobTracker will try its best to spread tasks across nodes provided they are empty slots. But again, this is not guaranteed.
> 2012/10/30 Marco Zühlke <[EMAIL PROTECTED]>
> Hi,
> on our cluster our jobs usually satisfied with less than 2 GB of heap space.
> so we have on our 8 GB computers 3 maps maximum and on our 16 GB
> computers 4 maps maximum (we only have quad core CPUs and to have
> memory left for reducers). This works very well.
> But now we have a new kind of jobs. Each mapper requires at lest 4 GB
> of heap space.
> Is it possible to limit the number of tasks (mapper) per computer to 1 or 2 for
> these kinds of jobs ?
> Regards,
> Marco
> --
> Have a Nice Day!
> Lohit

Arun C. Murthy
Hortonworks Inc.