-Re: observation while running hbase under load
Ted Yu 2013-08-30, 00:02
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
> > 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
> > in performance of insert or update . I thought even insert should have
> > blocked while read or scan is happening on the same rowkey , a lock will
> > 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