From: Rory Campbell-Lange <rory@campbell-lange.net>
To: pgsql-performance@postgresql.org
Subject: Comments requested on IO performance : new db server
Date: Fri, 9 Mar 2012 11:15:58 +0000
Message-ID: <20120309111558.GA22643@campbell-lange.net> (raw)
I've taken the liberty of reposting this message as my addendum to a
long thread that I started on the subject of adding a new db server to
our existing 4-year old workhorse got lost in discussion.
Our workload is several small databases totalling less than 40GB of disk
space. The proposed system has 48GB RAM, 2 * quad core E5620 @ 2.40GHz
and 4 WD Raptors behind an LSI SAS card. Our supplier has just run a set
of tests on the machine we intend to buy. The test rig had the following
setup:
LSI MegaRAID SAS 9260-8i
Firmware: 12.12.0-0090
Kernel: 2.6.39.4
Hard disks: 4x WD6000BLHX
Test done on 256GB volume
BS = blocksize in bytes
The test tool is fio. I'd be grateful to know if the results below are
considered acceptable. An ancillary question is whether a 4096 block
size is a good idea. I suppose we will be using XFS which I understand
has a default block size of 4096 bytes.
RAID 10
--------------------------------------
Read sequential
BS MB/s IOPs
512 0129.26 264730.80
1024 0229.75 235273.40
4096 0363.14 092965.50
16384 0475.02 030401.50
65536 0472.79 007564.65
131072 0428.15 003425.20
--------------------------------------
Write sequential
BS MB/s IOPs
512 0036.08 073908.00
1024 0065.61 067192.60
4096 0170.15 043560.40
16384 0219.80 014067.57
65536 0240.05 003840.91
131072 0243.96 001951.74
--------------------------------------
Random read
BS MB/s IOPs
512 0001.50 003077.20
1024 0002.91 002981.40
4096 0011.59 002968.30
16384 0044.50 002848.28
65536 0156.96 002511.41
131072 0170.65 001365.25
--------------------------------------
Random write
BS MB/s IOPs
512 0000.53 001103.60
1024 0001.15 001179.20
4096 0004.43 001135.30
16384 0017.61 001127.56
65536 0061.39 000982.39
131072 0079.27 000634.16
--------------------------------------
--
Rory Campbell-Lange
rory@campbell-lange.net
Campbell-Lange Workshop
www.campbell-lange.net
0207 6311 555
3 Tottenham Street London W1T 2AF
Registered in England No. 04551928
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Reply to all the recipients using the --to and --cc options:
reply via email
To: pgsql-performance@postgresql.org
Cc: rory@campbell-lange.net
Subject: Re: Comments requested on IO performance : new db server
In-Reply-To: <20120309111558.GA22643@campbell-lange.net>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox