Re: Same stament sometime fast, something slow - Mailing list pgsql-performance

From Craig Ringer
Subject Re: Same stament sometime fast, something slow
Date
Msg-id 4D23C843.8040804@postnewspapers.com.au
Whole thread Raw
In response to Same stament sometime fast, something slow  (Fernando Mertins <fernando.mertins@gmail.com>)
List pgsql-performance
On 01/05/2011 05:03 AM, Fernando Mertins wrote:
> Hi there, this is my first post.
>
> I have a PostgreSQL 8.3.6, compiled by Visual C++ build 1400 running on
> Windows with virtual machine
           ^^^^^^^^^^^^^^^^^^^^

What kind of VM host? where? what else is on the same host?

Your most likely culprit is I/O contention from other guests on the same
host, possibly combined with I/O queuing policies on the host that
favour throughput over request latency.

Checkpoints might also be a factor.

--
Craig Ringer

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