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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Ravi Krishna <s.ravikrishna@aim.com>
cc: pgsql-admin@postgresql.org
Subject: Re: WAL and O_DIRECT
In-reply-to: <14d530df35f-2108-30ce7@webstg-m03.mail.aol.com>
References: <14d530df35f-2108-30ce7@webstg-m03.mail.aol.com>
Comments: In-reply-to Ravi Krishna <s.ravikrishna@aim.com>
 message dated "Thu, 14 May 2015 11:32:12 -0400"
Date: Thu, 14 May 2015 11:55:33 -0400
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Ravi Krishna <s.ravikrishna@aim.com> writes:
> However our DB2 folks are raising a concern that PG WAL writes may not be crash safe, unless we are using write back technology in SAN or SSD , which we are using.

What's your point exactly?  If the underlying hardware does not provide
durable writes, there's nothing PG (or DB2) can do to fix that.

			regards, tom lane


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