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From: Josh Berkus <josh@agliodbs.com>
To: postgres performance list <pgsql-performance@postgresql.org>
Subject: Re: PostgreSQL as a local in-memory cache
Date: Thu, 24 Jun 2010 14:37:35 -0700
Message-ID: <4C23D01F.5060607@agliodbs.com> (raw)
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> this is similar MySQL's memory tables. Personally, I don't see any
> practical sense do same work on PostgreSQL now, when memcached exists.

Thing is, if you only have one table (say, a sessions table) which you
don't want logged, you don't necessarily want to fire up a 2nd software
application just for that.  Plus, recent testing seems to show that with
no logging, memcached isn't really faster than PG.

Also, like for asynch_commit, this is something where users are
currently turning off fsync.  Any option where we can present users with
controlled, predictable data loss instead of random corruption is a good
one.

> Much more important is smarter cache controlling then we have now -
> maybe with priorities for some tables and some operations
> (applications) - sometimes we don't need use cache for extra large
> scans.

Well, that would be good *too*.  You working on it?  ;-)

-- 
                                  -- Josh Berkus
                                     PostgreSQL Experts Inc.
                                     http://www.pgexperts.com



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