From: Heikki Linnakangas <heikki@enterprisedb.com>
To: Dimitri <dimitrik.fr@gmail.com>
Cc: PostgreSQL Performance <pgsql-performance@postgresql.org>
Subject: Re: Filesystem Direct I/O and WAL sync option
Date: Tue, 03 Jul 2007 16:06:29 +0100
Message-ID: <468A65F5.8020800@enterprisedb.com> (raw)
In-Reply-To: <5482c80a0707030754o740c82b6s4598dc668720d014@mail.gmail.com>
References: <5482c80a0707030754o740c82b6s4598dc668720d014@mail.gmail.com>
Dimitri wrote:
> I'm very curious to know if we may expect or guarantee any data
> consistency with WAL sync=OFF but using file system mounted in Direct
> I/O mode (means every write() system call called by PG really writes
> to disk before return)...
You'd have to turn that mode on on the data drives as well to get
consistency, because fsync=off disables checkpoint fsyncs of the data
files as well.
--
Heikki Linnakangas
EnterpriseDB http://www.enterprisedb.com
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To: pgsql-performance@postgresql.org
Cc: heikki@enterprisedb.com, dimitrik.fr@gmail.com
Subject: Re: Filesystem Direct I/O and WAL sync option
In-Reply-To: <468A65F5.8020800@enterprisedb.com>
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