On Tue, Mar 31, 2009 at 3:37 AM, <Chris.Ellis@shropshire.gov.uk> wrote:
>
> Hi
>
> Been having interesting times with an IBM x3650 with 8 15k RPM 73GB drives
> in RAID 10 and a ServRAID 8K controller with Write-Back cache enabled
> (battery installed and working). Currently getting a pgbench score of 4.7
> transactions per second! After playing with the postgresql configuration
> file, I'm certain that this is not a postgresql problem. I have tried two
> different Linux distro's upon the server both with the same problems. I'm
> fairly certain that this is a problem with the hardware configuration /
> setup, however I'm still waiting for IBM to contact me!
>
> Initially I started with the OS on a RAID 1 array and a 6 drive RAID 10
> array for postgresql. With this setup I got 3tps, altering the RAID
> configuration to a single 8 drive array, running both the OS and postgresql.
> I was able to reach 700tps, however after upgrading to the latest RAID
> controller firmware this has now fallen back to 4tps.
>
> Benchmarking another server I have access to, 4 15k 73GB RPM disks with a
> Dell Perc 5/i controller. I consistently get a pgbench score of 1400tps.
> Therefore taking a linear extrapolation I expect the IBM x3650 to manage
> ~3000tps. Additionally my Laptop with a 5400 RPM sata disk was able to
> score ~200tps.
SNIP
> What SAS RAID controllers are people using?
>
> What RAID configurations are people using?
>
> What SAS RAID controllers would anyone recommend purchasing?
I am using an Areca 1680 series controller. 16 SAS 15k5 disks. 2
RAID-1, 12 RAID-10, 2 hot spares. 512Meg bbu. RHEL 5.2 I can sustain
around 3000 tps with pgbench and 30 minute runs.
I'd call IBM and ask them to come pick up their boat anchors.
