From: PFC <lists@peufeu.com>
To: pgsql-performance@postgresql.org
Subject: Re: wal sync method
Date: Wed, 01 Mar 2006 12:58:21 +0100
Message-ID: <op.s5qgvjilcigqcu@apollo13> (raw)
In-Reply-To: <3867.1141170306@sss.pgh.pa.us>
References: <200602280114.k1S1EAQ17159@candle.pha.pa.us>
<op.s5piavelcigqcu@apollo13>
<3867.1141170306@sss.pgh.pa.us>
Hm, i seem to have mixed fwrite() (which buffers data in userspace) and
write() (which apparently doesnt !)
Sorry !
> PFC <lists@peufeu.com> writes:
>> Just a stupid question about the various fsync settings.
>> There is fsync=off, but is there fsync=fflush ?
>> fflush would mean only an OS crash could cause data loss,
>> I think.it could be useful for some applications where you need a speed
>> boost (like testing database import scripts...) without being as scary
>> as
>> fsync=off...
>
> I think you misunderstand. There aren't any scenarios where a PG crash
> (without hardware/OS crash) risks data, because we always at least
> write() data before commit. The only issue is how hard do we try to get
> the OS+hardware to push that data down to disk.
>
> regards, tom lane
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To: pgsql-performance@postgresql.org
Cc: lists@peufeu.com
Subject: Re: wal sync method
In-Reply-To: <op.s5qgvjilcigqcu@apollo13>
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