Re: Postgresql Performance on an HP DL385 and

Steve,

On 8/8/06 9:57 AM, "Steve Poe" <steve(dot)poe(at)gmail(dot)com> wrote:

> On the Sun box, with 4 discs (RAID10) to one channel on the LSI RAID card, I
> see an average TPS around 70. If I ran this off of one disc, I see an average
> TPS of 32.
>
> on the HP box, with 6-discs in RAID10 and 1 spare. I see a TPS of 34. I don't
> have my vmstat reports with me, but I recall the CPU utilitization on the HP
> was about 50% higher. I need to check on this.

Sounds like there are a few moving parts here, one of which is the ODBC
driver.

First - using 7.4.x postgres is a big variable - not much experience on this
list with 7.4.x anymore.

What OS versions are on the two machines?

What is the network configuration of each - is a caching DNS server
available to each? What are the contents of /etc/resolv.conf?

Have you run "top" on the machines while the benchmark is running? What is
the top running process, what is it doing (RSS, swap, I/O wait, etc)?

Are any of the disks not healthy? Do you see any I/O errors in dmesg?

Note that tarring up the database directory and untarring it actually
changes the block layout of the files on the disk from what the database
might have done when it was created. When you create a tar archive of the
files in the DB directory, their contents will be packed in file name order
in the tar archive and unpacked that way as well. By comparison, the
ordering when the database lays them on disk might have been quite
different. This doesn't impact the problem you describe as you are
unpacking the tar file on both machines to start the process (right?).

- Luke