Disk performance analysis

hpuxsa — Sun, 20 Mar 2005 04:38:20 GMT

I was comparing a measureware output for disk performance. The disk mentioned below is a 34GB Meta disk in an EMC array and is made of 4 * 8GB slices. If you see below the same disk has Disk util% as 88% when it has low values for reads, IO's, Bytes transferred only writes is high. Could some one explain how the disk util% is calculated.

Path Phy rd Phy wr Phy IO Phy KB Disk%
X.X.7.6 88025 328 88474 826286 88.56
X.X.7.6 128430 270 128790 1198080 55.17

Please find below another disk which is also a 34GB meta disk made of 4 * 8GB slices

X.X.8.1 92959 119 93168 979763 100

but here the disk util% is 100 but the values are very less compared to the previous output of 55% utilization. How is this possible.

Also find below another output just to show that high write does not change the utilization % too much.
X.X.8.1 38152 3348 41590 411872 40.29
X.X.8.1 27930 690 28710 278970 50.87

Does anyone have some optimum values for the stats we get from mwa for disk, network, mem, cpu etc. I know this depends a lot on our config but for some general stuff like for the disk mentioned above or for example for a 1GB NIC etc..

Re: Disk performance analysis

harry d brown jr — Sun, 20 Mar 2005 06:57:23 GMT

CACHE

disk utilization is based upon cache hits, not amount of IO

live free or die
harry d brown jr

topic Re: Disk performance analysis in Operating System - HP-UX

Disk performance analysis

Re: Disk performance analysis