topic How to get CCISS disk stats in Operating System - Linux

How to get CCISS disk stats

Marek Podmaka — Wed, 28 Jun 2006 06:27:44 GMT

Hello,
is there a way to get blocks read/written per second to disk when using HP SmartArray 532 (cciss driver in kernel)?
For IDE disks, this data is for example in /proc/diskstats, but for cciss, some numbers are simply zero.

For example:
104 0 cciss/c0d0 6068090 140796 0 59423472 6910399 7410784 0 756416616 0 57831244 815849076
104 1 cciss/c0d0p1 262104 3240564 1733149 3466298
104 2 cciss/c0d0p2 9311 74488 11293 90344
3 0 hda 1222417 14770 20531014 4574328 282550 2276383 20471632 31887560 0 5363868 36461880
3 1 hda1 17678 1631178 110626 884984
3 2 hda2 10937 130738 328066 2624472

Is there a way how to get this info? Or the cciss driver does not provide it?

Re: How to get CCISS disk stats

Ulf Zimmermann — Mon, 17 Jul 2006 19:32:00 GMT

iostat will show you stats:

iostat -d -x /dev/cciss/c0d0 1

Device: rrqm/s wrqm/s r/s w/s rsec/s wsec/s rkB/s wkB/s avgrq-sz avgqu-sz await svctm %util
cciss/c0d0 0.06 26.38 14.14 17.84 706.67 353.84 353.34 176.92 33.16 0.19 5.82 0.58 1.85

Device: rrqm/s wrqm/s r/s w/s rsec/s wsec/s rkB/s wkB/s avgrq-sz avgqu-sz await svctm %util
cciss/c0d0 0.00 0.00 0.00 3.96 0.00 31.68 0.00 15.84 8.00 0.01 3.50 1.50 0.59

Device: rrqm/s wrqm/s r/s w/s rsec/s wsec/s rkB/s wkB/s avgrq-sz avgqu-sz await svctm %util
cciss/c0d0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

This command will print out the stats once a second.

Re: How to get CCISS disk stats

Marek Podmaka — Mon, 17 Jul 2006 21:14:28 GMT

Thanks for your reply, but unfortunately the "iostat" command just takes the info from the /proc/diskstats file (see manpage for the -x option). So still I don't get some of the fields (the rsec/s or rkB/s are always zero).

Device: rrqm/s wrqm/s r/s w/s rsec/s wsec/s rkB/s wkB/s avgrq-sz avgqu-sz await svctm %util
cciss/c0d0 0.46 23.54 19.28 22.59 0.00 0.00 0.00 0.00 0.00 0.56 13.36 4.44 18.60

But it is strange as in your output I see every field is non-zero. I have official kernel 2.6.16.18 and this is information about the controller and cciss driver:

cartman:~:# cat /proc/driver/cciss/cciss0
cciss0: HP Smart Array 532 Controller
Board ID: 0x40820e11
Firmware Version: 2.62
IRQ: 169
Logical drives: 2
Current Q depth: 0
Current # commands on controller: 0
Max Q depth since init: 192
Max # commands on controller since init: 305
Max SG entries since init: 31

cciss/c0d0: 72.83GB RAID 1(1+0)
cciss/c0d1: 18.20GB RAID 1(1+0)