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From: Andreas Karlsson <andreas@proxel.se>
To: GR Vishwanath <grv144@gmail.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: Does fsync on/off for wal AND Checkpoint?
Date: Fri, 27 Dec 2013 17:27:14 +0100
Message-ID: <52BDAA62.9000600@proxel.se> (raw)
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On 12/27/2013 04:55 PM, GR Vishwanath wrote:
> Is fscnc off/on pertain only to writing WAL buffers to disk?
>
> Or is that also relevant to writing of dirty buffers to disk
> (checkpoint/bg)?
>
> Curious because in the docs fsync on/off is mentioned under WAL
> configuration.  Further there is a wal_sync_method but not a
> "checkpoint_sync_method".

The setting is for all uses of fsync within the PostgreSQL server, so if 
you turn it off PostgreSQL should never issue fsync. The only exceptions 
are some utility tools (eg. pg_basebackup) which do not read the 
configuration file.

-- 
Andreas Karlsson


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