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