Re: wal_buffers = -1 - Mailing list pgsql-hackers

From Magnus Hagander
Subject Re: wal_buffers = -1
Date
Msg-id CABUevEwuMFf+5KwbrsRY_mh88up6e2iErKeamzS6Yiv-i8LHEw@mail.gmail.com
Whole thread Raw
In response to Re: wal_buffers = -1  (Thom Brown <thom@linux.com>)
Responses Re: wal_buffers = -1  (Thom Brown <thom@linux.com>)
Re: wal_buffers = -1  (Robert Haas <robertmhaas@gmail.com>)
List pgsql-hackers
On Fri, Jan 17, 2014 at 2:07 PM, Thom Brown <thom@linux.com> wrote:
On 17 January 2014 13:01, Magnus Hagander <magnus@hagander.net> wrote:
> Is there any real use-case for not setting wal_buffers to -1 these days?
>
> Or should we just remove it and use the -1 behaviour at all times?
>
> IIRC we discussed not keeping it at all when the autotune behavior was
> introduced, but said we wanted to keep it "just in case". If we're not ready
> to remove it, then does that just mean that we need to fix it so we can?

Robert Haas reported that setting it to 32MB can yield a considerable
performance benefit:

http://www.postgresql.org/message-id/CA+TgmobgMv_aaakLoasBt=5iYfi=kdcOUz0X9TdYe0c2SZ=2Pg@mail.gmail.com

In that case, sholdn't the autotuning be changed to not limit it at 16MB? :) 

--
 Magnus Hagander
 Me: http://www.hagander.net/
 Work: http://www.redpill-linpro.com/

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