From: Josh Berkus <josh@agliodbs.com>
To: pgsql-performance@postgresql.org
Cc: Ulrich Wisser <ulrich.wisser@relevanttraffic.se>
Subject: Re: Need for speed
Date: Wed, 17 Aug 2005 10:28:04 -0700
Message-ID: <200508171028.05028.josh@agliodbs.com> (raw)
In-Reply-To: <4303003B.3020407@relevanttraffic.se>
References: <Pine.LNX.4.44.0508162045480.2995-100000@zigo.dhs.org>
<4303003B.3020407@relevanttraffic.se>
Ulrich,
> I believe the biggest problem is disc io. Reports for very recent data
> are quite fast, these are used very often and therefor already in the
> cache. But reports can contain (and regulary do) very old data. In that
> case the whole system slows down. To me this sounds like the recent data
> is flushed out of the cache and now all data for all queries has to be
> fetched from disc.
How large is the database on disk?
> My machine has 2GB memory, please find postgresql.conf below.
hmmmm ...
effective_cache_size?
random_page_cost?
cpu_tuple_cost?
etc.
--
Josh Berkus
Aglio Database Solutions
San Francisco
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To: pgsql-performance@postgresql.org
Cc: josh@agliodbs.com, ulrich.wisser@relevanttraffic.se
Subject: Re: Need for speed
In-Reply-To: <200508171028.05028.josh@agliodbs.com>
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