Re: Advice sought : new database server

On 08/03/12, Ants Aasma (ants(dot)aasma(at)eesti(dot)ee) wrote:

> So regardless if the benchmark is a good representation of the target
> workload or not, it definitely isn't benchmarking the IO system.

At the risk of hijacking the thread I started, I'd be grateful for
comments on the following system IO results. Rather than using pgbench
(which Ants responded about above), this uses fio. 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. Is this IO respectable?

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

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
--------------------------------------

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Rory Campbell-Lange
rory(at)campbell-lange(dot)net

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