Re: more 10K disks or less 15K disks

Iñigo Martinez Lasala <imartinez@xxxxxxxxxxxx> · Wed, 28 Apr 2010 22:29:14 +0200

Supposing a 50% performance increase disk-by-disk with 15.000rpm vs 10.000rpm you would get better performance (100%) by doubling number of disks versus using 15K rpm disk (50%).

However, you have to check other parameters, for example, if your RAID controller can deal with such a high bandwidth or the disk cache size. 

Do you have benchmarks about these hard disk models ?

How about using SSD? ;-)

-----Original Message-----

From: Anj Adu <fotographs@xxxxxxxxx>

To: pgsql-admin@xxxxxxxxxxxxxx

Subject:  more 10K disks or less 15K disks

Date: Wed, 28 Apr 2010 11:27:26 -0700

I am faced with a  hardware choice for a postgres data warehouse
(extremely high volume inserts..over 200 million records a day) with a
total storage of either

12 x 600G disks (15K)  (the new Dell Poweredge C server)

or

24 x 600G  (10K disks)

ALL direct attached storage.

I am leaning toward the 24 disks as I expect the higher number of
disks to provide overall better performance under high loads

Does anyone have any experience with a mixed 10K / 15K DAS storage
that you can share.

Thank you

Sriram