Re: race condition in sync rep

On Sat, Mar 26, 2011 at 4:24 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Simon Riggs <simon@2ndQuadrant.com> writes:
>> On Sat, Mar 26, 2011 at 4:04 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>>> In particular, in view of today's fix, shouldn't this commit be reverted?
>>>
>>> http://git.postgresql.org/gitweb?p=postgresql.git;a=commitdiff;h=6e8e7cc580665ddd43c8ca2acc6d60f345570a57
>>>
>>> I thought at the time that that was nothing more than documenting a
>>> known bug, and now it is documenting a dead bug.
>
>> No, that doc change is still accurate.
>
> Well, in that case, it should be on the open-items list.  If the system
> is still behaving that way, it's a bug.

Is it? Sync rep requires fsync on the standby. If you then explicitly
turn off fsync on the standby then it has a performance impact, as
documented.

Setting shared_buffers very low also reduces performance.

--
 Simon Riggs                   http://www.2ndQuadrant.com/
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