Thanks for pointing about setCacheBlocks() ,
its HBase default value will provide better performance for following
Filters as well as for Kevin's multiple Facet search.

-Alok

On Fri, Apr 20, 2012 at 7:02 AM, Kevin M <[email protected]> wrote:

> Thanks for pointing me towards setCacheBlocks() and explaining the
> difference between those two types of caching in HBase.
>
> According to the API documentation, setCacheBlocks defaults to true, so it
> looks like HBase will take care of what I am looking for automatically.
> Thanks so much for your answer, Alex.
>
> -Kevin
>
> On Thu, Apr 19, 2012 at 9:03 PM, Alex Baranau <[email protected]
> >wrote:
>
> > Regarding caching during scans there are two types of caches:
> > * caching (bufferring) the records before returning them to the client,
> > enabled via scan.setCaching(numRows)
> > * block cache on a regionserver, enabled via setCacheBlocks(true)
> >
> > The latter one (block cache) is what you are looking for.
> >
> > Note: setCacheBlocks(true) will not override your columnfamily settings,
> so
> > do not disable it on that level.
> >
> > Alex Baranau
> > ------
> > Sematext :: http://blog.sematext.com/ :: Solr - Lucene - Hadoop - HBase
> >
> > On Thu, Apr 19, 2012 at 12:52 PM, Kevin M <[email protected]>
> > wrote:
> >
> > > Thanks for the reply.
> > >
> > > I see. Would HBase cache the results of the first scan so it wouldn't
> > take
> > > as
> > > long to collect the results? Say there were 5 facets selected one after
> > > another.
> > > A new scan would take place with more strict filtering each time on the
> > > whole
> > > table rather than to use the results of the previous scan?
> > >
> > > Thank you.
> > >
> > >
> > >
> > >
> >
>

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