Re: requested shared memory size overflows size_t - Mailing list pgsql-performance

From Robert Haas
Subject Re: requested shared memory size overflows size_t
Date
Msg-id AANLkTinl1XU1IYUv2lmBXeKPKk37TKutBSNbcGvPmjJI@mail.gmail.com
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In response to Re: requested shared memory size overflows size_t  (Tom Wilcox <hungrytom@gmail.com>)
Responses Re: requested shared memory size overflows size_t
List pgsql-performance
On Mon, Jun 14, 2010 at 2:53 PM, Tom Wilcox <hungrytom@gmail.com> wrote:
> maintenance_work_mem=4GB
> work_mem=4GB
> shared_buffers=4GB
> effective_cache_size=4GB
> wal_buffers=1GB

It's pretty easy to drive your system into swap with such a large
value for work_mem - you'd better monitor that carefully.

The default value for wal_buffers is 64kB.  I can't imagine why you'd
need to increase that by four orders of magnitude.  I'm not sure
whether it will cause you a problem or not, but you're allocating
quite a lot of shared memory that way that you might not really need.

--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise Postgres Company

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