filesystem performance

[Florian Smeets]

On 05.05.09 07:30, Mark Wong wrote:
> Hi everyone,
>
> We (PostgreSQL community) have a HP DL380 G5 that we were using to do
> some very basic filesystem characterizations as part of a database
> performance tuning project, so we wanted to give FreeBSD a try out of
> the box.  For this set of data we used 7.1.  We're (us few that are
> running the tests) are fairly unfamiliar with the community here, so
> I'll be as brief as I can.  We're basically wondering if the data
> we're getting out of the box is expected, and any tuning guidelines
> including what changes we should expect to see in the performance.
>

I guess you are using the ciss driver in this box? There was a 
performance regression in this driver in 7.1. This should be fixed in 
7.2, which came out recently. It is believed that you should get a whole 
lot better IO performance with 7.2 if you are using the ciss driver.

 From the 7.2 release notes:

A bug in the ciss(4) driver which caused low “max device openings” count 
and led to poor performance has been fixed.

HTH,
Florian