Performance using MSA1500cs with MSA20 in ADG configuration.

[Ingemar Fällman]

Hi

What is the minimum and maximum write and read performance I should get from a raid 6 configuration?

In our configuration we get about 49Mb/s peak performance and about 30Mb/s in average.

Show tech_support output is attached.

The server is connected via fibre channel, and the fibre channel switch is only used for this server.

Server information:

Model: ProLiant DL380 G4
Serial numer: GB86111KLN
OS: Redhat / Red Hat Enterprise Linux AS release 4 (Nahant Update 5) / #1 SMP Fri Apr 20 17:03:35 EDT 2007
Fibre Channel: QLogic Corp. ISP2312-based 2Gb Fibre Channel to PCI-X HBA

Units are created using:

add unit 0 raid_level=ADG stripe_size=64 size=1572GB data="Disk101-Disk111"
add unit 1 raid_level=ADG stripe_size=64 size=1572GB data="Disk101-Disk111"
add unit 2 raid_level=ADG stripe_size=64 size=1572GB data="Disk101-Disk111"
add unit 3 raid_level=ADG stripe_size=64 size=1609159MB data="Disk101-Disk111"
add spare unit=0 "Disk112"

Filesystems are created with:

mkfs.ext3 -b 4096 -T largefile4 -m 0 -O sparse_super -O dir_index -R stride=16 -j -J size=400 /dev/sdm1
tune2fs -i 0 -c 0 /dev/sdm1
mkfs.ext3 -b 4096 -T largefile4 -m 0 -O sparse_super -O dir_index -R stride=16 -j -J size=400 /dev/sdn1
tune2fs -i 0 -c 0 /dev/sdn1
mkfs.ext3 -b 4096 -T largefile4 -m 0 -O sparse_super -O dir_index -R stride=16 -j -J size=400 /dev/sdo1
tune2fs -i 0 -c 0 /dev/sdo1
mkfs.ext3 -b 4096 -T largefile4 -m 0 -O sparse_super -O dir_index -R stride=16 -j -J size=400 /dev/sdp1
tune2fs -i 0 -c 0 /dev/sdp1


We performed the benchmark using dd, with direct file write to prevent write cache in Linux.

# cat /home/bigfile00 > /dev/null; sync; /bin/nice -n -10 /home/dd if=/home/bigfile00 of=/fc/unit200/fot/bigfile02 oflag=direct bs=1024k; sync
1024+0 records in
1024+0 records out
1073741824 bytes (1.1 GB) copied, 24.4965 seconds, 43.8 MB/s

[Ingemar Fällman]

Did not realize that this was a public forum, can a moderatior please remove the serialnumber from my post.

[Megan Moore]

How and why are you specifing the stride size?

I though you may have an alignment problem.