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From: Bijieshan <bijieshan@huawei.com>
To: "user@hbase.apache.org" <user@hbase.apache.org>
CC: Zhouxunmiao <zhouxunmiao@huawei.com>
Subject: RE: scan is slower after bulk load
Thread-Topic: scan is slower after bulk load
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Date: Tue, 13 Nov 2012 00:29:06 +0000
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I think one possible reason is block caching. Have you turned the block cac=
hing off during scanning?

Regards,
  Jieshan
________________________________________
From: Mohammad Tariq [dontariq@gmail.com]
Sent: Tuesday, November 13, 2012 1:04
To: user@hbase.apache.org
Subject: Re: scan is slower after bulk load

may be because bulk load writes to the same region thus putting the entire
load on a single region server.

Regards,
    Mohammad Tariq


On Mon, Nov 12, 2012 at 9:15 PM, Michael Segel <michael_segel@hotmail.com>w=
rote:

> Just a guess... have you done any compactions on the table post bulk load=
?
>
> On Nov 12, 2012, at 8:44 AM, Marcos Ortiz <mlortiz@uci.cu> wrote:
>
> > Regards, Amit.
> > Did you tuned the RegionServer where you has that data range hosted?
> > Why do you say that scans are slower after a bulk load?
> > Did you test it before bulk load?
> >
> > HBase version?
> >
> > On 11/12/2012 09:39 AM, Amit Sela wrote:
> >> Hi all,
> >>
> >> Anyone has any idea why scanning over specific range in a table is abo=
ut
> >> 20% slower if that data (that specific range) was just inserted into
> HBase
> >> using bulk load ?
> >>
> >> I do the bulk load programmatically with  LoadIncrementalHFiles.
> >>
> >> Thanks.
> >>
> >
> > --
> >
> > Marcos Luis Ort=EDz Valmaseda
> > about.me/marcosortiz <http://about.me/marcosortiz>
> > @marcosluis2186 <http://twitter.com/marcosluis2186>
> >
> >
> >
> > 10mo. ANIVERSARIO DE LA CREACION DE LA UNIVERSIDAD DE LAS CIENCIAS
> INFORMATICAS...
> > CONECTADOS AL FUTURO, CONECTADOS A LA REVOLUCION
> >
> > http://www.uci.cu
> > http://www.facebook.com/universidad.uci
> > http://www.flickr.com/photos/universidad_uci
>
>