Disk Usage

Hi Experts,

glance is showing disk util 100% on of production domain and while collecting sar data using sar -d 5 5, avserv for some of the disks are more than 10 miliseconds. Need your advise on steps that needs to be taken to reduce the disk utilitzation.

device   %busy   avque   r+w/s  blks/s  avwait  avserv
Average  c63t11d6    3.12    0.50       1      27    0.00   35.10
Average   c80t8d1    0.12    0.50       0       4    0.00    2.58
Average  c42t14d6    0.04    0.50       0       0    0.00    2.57
Average   c82t8d6    0.64    0.50       0       4    0.00   26.92
Average  c58t15d5    0.32    0.50       0       4    0.00   12.41
Average   c42t3d3    0.24    0.50       1      44    0.00    4.61
Average   c52t9d6    0.04    0.50       0       0    0.00   15.81
Average   c47t9d6    0.04    0.50       0       0    0.00    2.32
Average   c52t9d7    0.08    0.50       0       0    0.00   15.90
 
prod:root:/# model
9000/800/SD32B
prod:root:/#
 

OS: HP-UX
Version :B.11.11

Is that the "Current", "Average" or "High" figure in Glance? How long were you running Glance for?

Looking at the disc system for 25 seconds isn't going to mean a lot. Try running sar for 30 mins if you are looking for a hot disc.

sar -d 10 180|egrep "Average|device"

As mentioned on your CPU thread, the disc figures are meaningless without knowing about your disc configuration, partition placement, mirroring etc., and more about your software.

1 Like

Hi Methly,

Thanks for the reply,will observe disk util for the 30 mins and will post the result.

glance showing average value of disk util as 98% and current in 100%.

I am simply using glance command.(without any options)

Considering my limited knowledge at sys admin level,if possbile request you to provide me commands/resources so that I can provide the required details like disc configuration, partition placement, mirroring etc.

Thanks Again...

---------- Post updated 06-27-12 at 03:07 AM ---------- Previous update was 06-26-12 at 07:38 AM ----------

Will increasing dynamic buffer cache provide any help in reducing the disk utilization?

System has 40G of RAM and currnet values of dynamic buffer cache tuneble is as mentioned below.

 
kmtune |grep dbc_min_pct
dbc_min_pct                 5  -  5
 
kmtune |grep dbc_max_pct
dbc_max_pct                 5  -  5