Home | About | Sematext search-lucene.com search-hadoop.com
 Search Hadoop and all its subprojects:

Switch to Threaded View
HBase, mail # user - Excessive .META scans


Copy link to this message
-
Re: Excessive .META scans
Nicolas Liochon 2013-07-29, 17:43
It could be HBASE-6870?
On Mon, Jul 29, 2013 at 7:37 PM, Jean-Daniel Cryans <[EMAIL PROTECTED]>wrote:

> Can you tell who's doing it? You could enable IPC debug for a few secs
> to see who's coming in with scans.
>
> You could also try to disable pre-fetching, set
> hbase.client.prefetch.limit to 0
>
> Also, is it even causing a problem or you're just worried it might
> since it doesn't look "normal"?
>
> J-D
>
> On Mon, Jul 29, 2013 at 10:32 AM, Varun Sharma <[EMAIL PROTECTED]>
> wrote:
> > Hi folks,
> >
> > We are seeing an issue with hbase 0.94.3 on CDH 4.2.0 with excessive
> .META.
> > reads...
> >
> > In the steady state where there are no client crashes and there are no
> > region server crashes/region movement, the server holding .META. is
> serving
> > an incredibly large # of read requests on the .META. table.
> >
> > From my understanding, in the steady state, region locations should be
> > indefinitely cached in the client. The client is running a work load of
> > multiput(s), puts, gets and coprocessor calls.
> >
> > Thanks
> > Varun
>