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Re: observation while running hbase under load
This JIRA is related: HBASE-8836
On Thu, Aug 29, 2013 at 2:22 PM, RK S <[EMAIL PROTECTED]> wrote:

> Does Hbase gives higher Preference to Writes than Reads , if  one tries to
> do both operation for the same rowkey at the same time???
> My scenario
>
> Iam new to Hbase and Iam testing Hbase for our datawarehouse solution. Iam
> trying following 2 scenarios.
>
> >
> > 100000 Rows
> > Each of the Rowkey has 5000 Columns Qualifiers spread across 3 Column
> > families.
> >
> > I generate following 2 kinds of load.
> >
> > 1.
> >   1.1  Generate 100000 of rows , with sequential INSERT. By sequential
> > INSERT I mean
> >          Each time I do a insert of rowkey  also insert all  of the 5000
> > Column qualifiers . each insert also does some READS as some of the
> column
> > families act like Index.
> >   1.2  After Generation of Table using above , I perform READ , SCAN and
> > INSERT randomly column qualifier in random fashion.
> >
> > 2.
> >    Doing both Generation of Load (1.1 ) and doing read ,scan and insert
> > random column qualifier (1.2) in parallel
> >
> > Observed Behavior.
> >
> > While 2 is happening I can see that read ,scan take more than what they
> > use to take in 1 . This is fine as when  insert is happening read is
> > blocked as whole row is locked. But I do not see any significant
> difference
> > in performance of insert or update . I thought even insert should have
> been
> > blocked while read or scan is happening on the same rowkey , a lock will
> be
> > held for a given ROWKEY.
> > Please remember READ,SCAN and INSERT happen on the same Rowkeys.
> >
> > Question: Does hbase give preference to write than read or am I missing
> > something ?
> >
> > regards,
> > rks
> >
>