Re: SATA drives for DB?

In article <4176cbc9.789912524_at_localhost>, NetComrade <netcomradeNSPAM_at_bookexchange.net> wrote:
>All,
>
>I am trying to find some decent comparisons on 'budget' disk arrays.
>We are currently running on 4 Sun storegde a5200, and since we are

>Our shop is OLTP by day, batch by night. IO is really not an issue
>during the day, and we don't have any historical data on IO
>performance, other then statspack logs (taken hourly every day)

A fibre channel drive will do 300 IO operations per second and a SATA disk will maybe do 80. If you move from 88 Fibre channel disks to 10 SATA drives you will decrease system performace from 26400 IOPS to 800 IOPS. The SATA drive will do apx the same MB/s as the Fibre disk.

My guess is that the nightly batch jobs will take significantly longer using SATA.

Can I make 88 FC drives slower that 10 SATA drives using a RAID controller? Yes, but by using just insignificant brain power I can make 88FC drives 100xFASTER.

>'random IO that database generates'. Sun was trying to sell their
>3511FC Array (which also has a RAID controller). Currently our RAIDs
>are done via Veritas.

The Sun rep that tries to replace 4 5200:s with a 3511 is probably fired by now. However the 3510 can be a MUCH better solution.

/regards
Fredrik

-- 
Fredrik Lundholm   
dol @ ce.chalmers.se