Re: dell versus hp - Mailing list pgsql-performance

On Wed, 14 Nov 2007, Merlin Moncure wrote:

> On Nov 14, 2007 5:24 PM, Alan Hodgson <ahodgson@simkin.ca> wrote:
>> On Tuesday 13 November 2007, Jeff Frost <jeff@frostconsultingllc.com> wrote:
>>> Ok, Areca ARC1261ML.  Note that results were similar for an 8 drive RAID6
>>> vs 8 drive RAID10, but I don't have those bonnie results any longer.
>>>
>>> Version  1.03       ------Sequential Output------ --Sequential Input-
>>> --Random- -Per Chr- --Block-- -Rewrite- -Per Chr- --Block-- --Seeks--
>>> Machine        Size K/sec %CP K/sec %CP K/sec %CP K/sec %CP K/sec %CP
>>> /sec %CP 14xRAID6        63G 73967  99 455162  58 164543  23 77637  99
>>> 438570  31 912.2   1 ------Sequential Create------ --------Random
>>> Create-------- -Create-- --Read--- -Delete-- -Create-- --Read---
>>> -Delete-- files  /sec %CP  /sec %CP  /sec %CP  /sec %CP  /sec %CP  /sec
>>> %CP 16 12815  63 +++++ +++ 13041  61 12846  67 +++++ +++ 12871  59
>>>
>>>
>>> Version  1.03       ------Sequential Output------ --Sequential Input-
>>> --Random- -Per Chr- --Block-- -Rewrite- -Per Chr- --Block-- --Seeks--
>>> Machine        Size K/sec %CP K/sec %CP K/sec %CP K/sec %CP K/sec %CP
>>> /sec %CP 14xRAID10       63G 63968  92 246143  68 140634  30 77722  99
>>> 510904 36 607.8   0 ------Sequential Create------ --------Random
>>> Create-------- -Create-- --Read--- -Delete-- -Create-- --Read---
>>> -Delete-- files  /sec %CP  /sec %CP  /sec %CP  /sec %CP  /sec %CP /sec
>>> %CP 16  6655  16 +++++ +++  5755  12  7259  17 +++++ +++ 5550  12
>>
>> OK, impressive RAID-6 performance (not so impressive RAID-10 performance,
>> but that could be a filesystem issue). Note to self; try an Areca
>> controller in next storage server.
>
> 607 seeks/sec on a 8 drive raid 10 is terrible...this is not as
> dependant on filesystem as sequential performance...

Then this must be horrible since it's a 14 drive raid 10. :-/  If we had more
time for the testing, I would have tried a bunch of RAID1 volumes and
used software RAID0 to add the +0 bit and see how that performed.

Merlin, what sort of seeks/sec from bonnie++ do you normally see from your
RAID10 volumes?

On an 8xRAID10 volume with the smaller Areca controller we were seeing around
450 seeks/sec.

--
Jeff Frost, Owner     <jeff@frostconsultingllc.com>
Frost Consulting, LLC     http://www.frostconsultingllc.com/
Phone: 650-780-7908    FAX: 650-649-1954