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From: lars <lhofhansl@yahoo.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Kevin Grittner <Kevin.Grittner@wicourts.gov>
Cc: Ivan Voras <ivoras@freebsd.org>
Cc: pgsql-performance@postgresql.org
Subject: Re: UPDATEDs slowing SELECTs in a fully cached database
Date: Sat, 16 Jul 2011 19:12:47 -0700
Message-ID: <4E22451F.9070803@yahoo.com> (raw)
In-Reply-To: <464.1310658420@sss.pgh.pa.us>
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On 07/14/2011 08:47 AM, Tom Lane wrote:
>
> The implementation I was imagining was to define another bit in the info
> parameter for XLogInsert, say XLOG_NON_TRANSACTIONAL.  This could be a
> high-order bit that would not go to disk.  Anytime it was *not* set,
> XLogInsert would set a global boolean that would remember that the
> current transaction wrote a transactional WAL record.  This is the
> right default since the vast majority of call sites are writing records
> that we would want to have flushed at commit.  There are just a couple
> of places that would need to be changed to add this flag to their calls.
>
> 			regards, tom lane
>

If you have a patch in mind I'm happy to test it on my setup and report 
back.

-- Lars




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