DS3200
DS3200 performance tests #1
today I made some tests at DS3200, I’m fully dissapointed of it’s power, but maybe I do sth wrong? Take a look:
# mount |grep reiser
/dev/sde1 on /tmp/test type reiserfs (rw,noatime,nodiratime)
/dev/sdf1 on /tmp/test2 type reiserfs (rw,noatime,nodiratime)
/dev/sdg1 on /tmp/test3 type reiserfs (rw,noatime,nodiratime)
everything connected from dual controller IBM DS3200 (SAS), with SATA 750GB disks.
/dev/sde1 is raid0 at 4 disks
/dev/sdf1 is raid10 at 4 disks
/dev/sdg1 is raid5 at 4 disks
and the tests:
# dd if=/dev/zero of=/tmp/test/pliczek count=5000 bs=1M 5000+0 records in
5000+0 records out
5242880000 bytes (5.2 GB) copied, 66.6999 s, 78.6 MB/s
# dd if=/dev/zero of=/tmp/test2/pliczek count=5000 bs=1M
5000+0 records in
5000+0 records out
5242880000 bytes (5.2 GB) copied, 191.962 s, 27.3 MB/s
# dd if=/dev/zero of=/tmp/test3/pliczek count=5000 bs=1M
5000+0 records in
5000+0 records out
5242880000 bytes (5.2 GB) copied, 130.41 s, 40.2 MB/s
raid5 looks better than raid10?????
now read tests:
# dd if=/tmp/test/pliczek of=/dev/null count=5000 bs=1M
5000+0 records in
5000+0 records out
5242880000 bytes (5.2 GB) copied, 21.179 s, 248 MB/s
# dd if=/tmp/test2/pliczek of=/dev/null count=5000 bs=1M
5000+0 records in
5000+0 records out
5242880000 bytes (5.2 GB) copied, 33.007 s, 159 MB/s
# dd if=/tmp/test3/pliczek of=/dev/null count=5000 bs=1M
5000+0 records in
5000+0 records out
5242880000 bytes (5.2 GB) copied, 22.7079 s, 231 MB/s
why raid10 is much slower than raid5?
raid 10 at DS3200,3300,3400
In every marketing documentation I can find, that IBM TotalStorage DS3xxx series support RAID10. But reality is not always such nice as the marketing shit. The official ds3200 documenation says that It can do raid 10. Because as you can see below it is not listed:
I tried to do two raid 1 arrays and make a raid 0 from them, but it is imposible… So i have to read and search a lot of IBM Redbooks, and finaly find that:
When RAID level 1 is implemented and the number of drives increases to more than two, RAID level 10 is automatically implemented.
Very good news 
and it really works:
