From: Josh Berkus <josh@agliodbs.com>
To: pgsql-performance@postgresql.org
Cc: Luke Lonergan <llonergan@greenplum.com>
Subject: Re: random_page_costs - are defaults of 4.0 realistic for SCSI RAID 1
Date: Mon, 10 Sep 2007 14:26:40 -0700
Message-ID: <200709101426.41424.josh@agliodbs.com> (raw)
In-Reply-To: <C30AF4C7.4230B%llonergan@greenplum.com>
References: <C30AF4C7.4230B%llonergan@greenplum.com>
Luke,
> We (GP) have implemented
> something we call "Adaptive Nested Loop" to replace a nested loop +
> index scan with a hash join when the selectivity estimates are off in
> order to improve this behavior. We also run with a
> "random_page_cost=100" because we generally run on machines with fast
> sequential I/O.
So, when is this getting contributed? ;-)
--
--Josh
Josh Berkus
PostgreSQL @ Sun
San Francisco
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To: pgsql-performance@postgresql.org
Cc: josh@agliodbs.com, llonergan@greenplum.com
Subject: Re: random_page_costs - are defaults of 4.0 realistic for SCSI RAID 1
In-Reply-To: <200709101426.41424.josh@agliodbs.com>
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