Increase default effective_cache_size?

From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To: pgsql-hackers(at)postgreSQL(dot)org
Cc: Russ Brown <pickscrape(at)gmail(dot)com>
Subject: Increase default effective_cache_size?
Date: 2006-09-23 23:10:33
Message-ID: 29442.1159053033@sss.pgh.pa.us
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Russ Brown <pickscrape(at)gmail(dot)com> writes on pgsql-general:
> On Thu, 2006-09-21 at 23:39 -0400, Jim Nasby wrote:
>> Also make sure that you've set effective_cache_size
>> correctly (I generally set it to total memory - 1G, assuming the
>> server has at least 4G in it).

> Thank you: the problem was the effective_cache_size (which I hadn't
> changed from the default of 1000). This machine doesn't have loads of
> RAM, but I knocked it up to 65536 and now the query uses the index,
> without having to change the statistics.

Considering recent discussion about how 8.2 is probably noticeably more
sensitive to effective_cache_size than prior releases, I wonder whether
it's not time to adopt a larger default value for that setting. The
current default of 1000 pages (8Mb) seems really pretty silly for modern
machines; we could certainly set it to 10 times that without problems,
and maybe much more. Thoughts?

regards, tom lane

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