Re: RAID 0 not as fast as expected - Mailing list pgsql-performance

Alan Hodgson wrote:
> On Thursday 14 September 2006 11:05, "Craig A. James"
> <cjames@modgraph-usa.com> wrote:
>> I'm experiment with RAID, looking for an inexpensive way to boost
>> performance.  I bought 4 Seagate 7200.9 120 GB SATA drives and two SIIG
>> dual-port SATA cards.  (NB: I don't plan to run RAID 0 in production,
>> probably RAID 10, so no need to comment on the failure rate of RAID 0.)
>>
>
> Are those PCI cards?  If yes, it's just a bus bandwidth limit.

Ok, that makes sense.

   One SATA disk = 52 MB/sec
   4-disk RAID0  = 106 MB/sec

   PCI at 33 MHz x 32 bits (4 bytes) = 132 MB/sec.

I guess getting to 80% of the theoretical speed is as much as I should expect.

Thanks,
Craig