From: Luke Lonergan <llonergan@greenplum.com>
To: Vivek Khera <vivek@khera.org>
To: Postgresql Performance <pgsql-performance@postgresql.org>
Subject: Re: Hardware/OS recommendations for large databases (
Date: Fri, 18 Nov 2005 08:16:39 -0800
Message-ID: <BFA33E67.1404D%llonergan@greenplum.com> (raw)
In-Reply-To: <1F5BD2B1-8A75-498E-ADB7-8CB661066013@khera.org>
Vivek,
On 11/18/05 8:07 AM, "Vivek Khera" <vivek@khera.org> wrote:
>
> On Nov 18, 2005, at 10:13 AM, Luke Lonergan wrote:
>
>> Still, there is a CPU limit here this is not I/O bound, it is CPU limited
>> as evidenced by the sensitivity to readahead settings. If the filesystem
>> could do 1GB/s, you wouldn¹t go any faster than 244MB/s.
>
> Yeah, and mysql would probably be faster on your trivial queries. Try
> concurrent large joins and updates and see which system is faster.
That¹s what we do to make a living. And it¹s Oracle that a lot faster
because they implemented a much tighter, optimized I/O path to disk than
Postgres.
Since you asked, we bought the 5 systems as a cluster and with Bizgres MPP
we get close to 400MB/s per machine on complex queries.
- Luke
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To: pgsql-performance@postgresql.org
Cc: llonergan@greenplum.com, vivek@khera.org
Subject: Re: Hardware/OS recommendations for large databases (
In-Reply-To: <BFA33E67.1404D%llonergan@greenplum.com>
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