Re: I/O Performance and Disk Size

Just get the read/write seeks speeds for the disks to see how they compare. Should be able to get those from the manufacturers. Disk cache may be able to help speeds as well.

The big mistake made by most people when going to bigger drives is that they don't get enough of them. Someone needs 40GB of storage, so they get 2 or 3 18GB drives instead of 4 or 5 9GB drives (even better to get 7 or 8 9GB drives to spread things out better).

When it comes to disks, the throughput of I/O is just as important as the amount of storage. If your system needs to perform 2000 reads/seconds, and you have 4 disks that can each perform 300 reads per second (or 1200 reads per second total), then you have a bottleneck.

enjoy,

dave

In article <8fhnea$lig$1_at_nnrp1.deja.com>,   gary_arvan_at_my-deja.com wrote:
> Howdy, I'm a new Oracle DBA and I'm already in a debate with my
 developer
> friends regarding Disk I/O and Disk Size. Customer says the 1 Gig
 SCSI drives
> that are 5+ years old have quicker response than the newer and larger
 hard
> drives of today. He references performance data and magazine
 articles that
> are 5 or more years old that clearly show 1gig out performed the 10gig
> drives. But no current data! Consequently, we use 30 refurbished 1
 gig
> drives, and yes they do fail rather frequently.
>
> I'm thinking todays 10, 15 or 20 gig drives will out perform these
 older
> drives, but I have no performance data to back up my claim. Does
 anybody out
> there have metrics that I could use to justify my claim?
>
> Thanks
>
> Sent via Deja.com http://www.deja.com/
> Before you buy.
>

Sent via Deja.com http://www.deja.com/
Before you buy. Received on Fri May 12 2000 - 00:00:00 CDT