Hi All,
I read this thread of someone else experiencing terrible RAID5 performance:
http://ohioloco.ubuntuforums.org/sho....php?t=1643094
Mine is also terrible but didn't want to hijack the other thread.
Does anyone have any suggestions on what I can do to troubleshoot the issue further?
- Software Raid (MDADM)
- Performance is terrible locally, not just over the network. Can often > 60seconds to create a folder or to list files in a directory.
- 3GB RAM, E6300CPU
- 9.10 Karmic
- Low CPU utilisation during slow performance
- Low Memory utilisation during slow performance
Disks that make up the RAID5 array:
Code:
root@server:~# hdparm -tT /dev/sda
/dev/sda:
Timing cached reads: 2172 MB in 2.00 seconds = 1086.12 MB/sec
Timing buffered disk reads: 266 MB in 3.02 seconds = 88.10 MB/sec
root@server:~# hdparm -tT /dev/sdb
/dev/sdb:
Timing cached reads: 1724 MB in 2.00 seconds = 861.43 MB/sec
Timing buffered disk reads: 20 MB in 4.02 seconds = 4.98 MB/sec
root@server:~# hdparm -tT /dev/sdc
/dev/sdc:
Timing cached reads: 2536 MB in 2.00 seconds = 1268.59 MB/sec
Timing buffered disk reads: 280 MB in 3.02 seconds = 92.72 MB/sec
root@server:~# hdparm -tT /dev/sdd
/dev/sdd:
Timing cached reads: 1344 MB in 2.00 seconds = 671.60 MB/sec
Timing buffered disk reads: 20 MB in 4.21 seconds = 4.76 MB/sec
root@server:~# hdparm -tT /dev/sde
/dev/sde:
Timing cached reads: 2198 MB in 2.00 seconds = 1099.45 MB/sec
Timing buffered disk reads: 300 MB in 3.01 seconds = 99.60 MB/sec
root@server:~# hdparm -tT /dev/sdf
/dev/sdf:
Timing cached reads: 2532 MB in 2.00 seconds = 1266.33 MB/sec
Timing buffered disk reads: 290 MB in 3.02 seconds = 96.18 MB/sec
root@server:~# hdparm -tT /dev/sdg
Stand-alone Disks (system and one other)
Code:
root@server:~# hdparm -tT /dev/sdg
/dev/sdg:
Timing cached reads: 2210 MB in 2.00 seconds = 1104.42 MB/sec
Timing buffered disk reads: 262 MB in 3.01 seconds = 86.91 MB/sec
root@server:~# hdparm -tT /dev/sdh
/dev/sdh:
Timing cached reads: 2514 MB in 2.00 seconds = 1256.91 MB/sec
Timing buffered disk reads: 194 MB in 3.00 seconds = 64.64 MB/sec
root@server:~# hdparm -tT /dev/md0
The Actual MDADM array
Code:
/dev/md0:
Timing cached reads: 2518 MB in 2.00 seconds = 1259.05 MB/sec
Timing buffered disk reads: 14 MB in 3.84 seconds = 3.64 MB/sec
