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HBase, mail # user - What is causing my mappers to execute so damn slow?


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Pavan Sudheendra 2013-09-27, 17:33
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Jean-Daniel Cryans 2013-09-27, 17:42
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Pavan Sudheendra 2013-09-27, 18:07
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Re: What is causing my mappers to execute so damn slow?
Jean-Daniel Cryans 2013-09-27, 18:30
I don't think there's a CDH that includes Hadoop 1.2.1

So either your code is doing something slow or it's the reading itself. For
the latter, make sure you go through
http://hbase.apache.org/book.html#perf.reading and we also recently had
this thread on the list were you can see some "live" performance debugging
http://www.mail-archive.com/[EMAIL PROTECTED]/msg27174.html. For
example, make sure you're not running on the local job tracker.

J-D
On Fri, Sep 27, 2013 at 11:07 AM, Pavan Sudheendra <[EMAIL PROTECTED]>wrote:

> Hi Jean,
> HBase 0.94.6 and Hadoop 1.2.1 Cloudera Distributions..
>
> I infact tried that out, in place of doing the get operations , i created
> stub data and returned that instead.. It was practically at the same speed.
>
> Nothing changed.. After 20 mins or so when i check the job status.. It
> hardly reached 1,000,000 rows..
>
>
> On Fri, Sep 27, 2013 at 11:12 PM, Jean-Daniel Cryans <[EMAIL PROTECTED]
> >wrote:
>
> > Your details are missing important bits like you configurations,
> > Hadoop/HBase versions, etc.
> >
> > Doing those random reads inside your MR job, especially if they are
> reading
> > cold data, will indeed make it slower. Just to get an idea, if you skip
> > doing the Gets, how fast does it became?
> >
> > J-D
> >
> >
> > On Fri, Sep 27, 2013 at 10:33 AM, Pavan Sudheendra <[EMAIL PROTECTED]
> > >wrote:
> >
> > > Hi everyone,
> > > I posted this question many time before and i've given full details on
> > > stackoverflow..
> > >
> > > http://stackoverflow.com/q/19056712/938959
> > >
> > > Please i need someone to guide me in the right direction here.
> > >
> > > Help much appreciated!
> > >
> > > --
> > > Regards-
> > > Pavan
> > >
> >
>
>
>
> --
> Regards-
> Pavan
>