Re: Postgresql Performance on an HP DL385 and

Luke,

I thought so. In my test, I tried to be fair/equal since my Sun box has two
4-disc arrays each on their own channel. So, I just used one of them which
should be a little slower than the 6-disc with 192MB cache.

Incidently, the two internal SCSI drives, which are on the 6i adapter,
generated a TPS of 18.

I thought this server would impressive from notes I've read in the group.
This is why I thought I might be doing something wrong. I stumped which way
to take this. There is no obvious fault but something isn't right.

Steve

On 8/8/06, Luke Lonergan <LLonergan(at)greenplum(dot)com> wrote:
>
> Steve,
>
> > Sun box with 4-disc array (4GB RAM. 4 167GB 10K SCSI RAID10
> > LSI MegaRAID 128MB). This is after 8 runs.
> >
> > dbserver-dual-opteron-centos,08/08/06,Tuesday,20,us,12,2,5
> > dbserver-dual-opteron-centos,08/08/06,Tuesday,20,sy,59,50,53
> > dbserver-dual-opteron-centos,08/08/06,Tuesday,20,wa,1,0,0
> > dbserver-dual-opteron-centos,08/08/06,Tuesday,20,id,45,26,38
> >
> > Average TPS is 75
> >
> > HP box with 8GB RAM. six disc array RAID10 on SmartArray 642
> > with 192MB RAM. After 8 runs, I see:
> >
> > intown-vetstar-amd64,08/09/06,Tuesday,23,us,31,0,3
> > intown-vetstar-amd64,08/09/06,Tuesday,23,sy,16,0,1
> > intown-vetstar-amd64,08/09/06,Tuesday,23,wa,99,6,50
> > intown-vetstar-amd64,08/09/06,Tuesday,23,id,78,0,42
> >
> > Average TPS is 31.
>
> Note that the I/O wait (wa) on the HP box high, low and average are all
> *much* higher than on the Sun box. The average I/O wait was 50% of one
> CPU, which is huge. By comparison there was virtually no I/O wait on
> the Sun machine.
>
> This is indicating that your HP machine is indeed I/O bound and
> furthermore is tying up a PG process waiting for the disk to return.
>
> - Luke
>
>