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From: n keywal <nkeywal@gmail.com>
Date: Thu, 13 Sep 2012 18:42:41 +0200
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Subject: Re: read short circuit
To: dev@hbase.apache.org
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It's all in the "pretty much" :-)
Should we make it the default (i.e. recommending it in the doc, emitting a
warning if it's not set) for all installation ?
Or would it make sense to separate the store and wal cases, meaning that we
need a change in hdfs to make this possible?


On Thu, Sep 13, 2012 at 6:30 PM, Jean-Daniel Cryans <jdcryans@apache.org>wrote:

> On Thu, Sep 13, 2012 at 7:58 AM, n keywal <nkeywal@gmail.com> wrote:
> > Hi,
> >
> > Is there any known counter indication for read short circuit?
> > I had a look at JD's presentation from January. It was tested vs. HBase
> as
> > a whole; and still recommended for nearly all cases.
>
> Pretty much.
>
> >
> > We could make it at least the default when reading HLog files (even if it
> > seems it's a 'per client" config, there is may be something to look at as
> > well)?
>
> You have to add 2 configs in hdfs-site.xml, which we can't do from HBase.
>
> J-D
>

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