Re: corelation between %iowait from top and %busy or avwait from sar -d

From: MikeHT (mike2.li_at_gmail.com)
Date: 10/10/05 

Date: 10 Oct 2005 07:48:55 -0700

Hi:
I checked the status of the server (Machine A) this am (10:33 EDT).
%idle is high, %busy is very low, %iowait is low too. Anyone has
experience with EMC PowerPath 3.03? Thanks.

last pid: 7309; load averages: 0.55, 1.02, 1.10
10:33:43
173 processes: 172 sleeping, 1 on cpu
CPU states: 97.2% idle, 0.6% user, 0.7% kernel, 1.6% iowait, 0.0%
swap
Memory: 6144M real, 1299M free, 3097M swap in use, 3062M swap free

SunOS MachineA 5.8 Generic_117350-25 sun4u 10/10/05
Did a sar -d
10:36:16 device %busy avque r+w/s blks/s avwait avserv
10:36:20 md0 0 0.0 0 4 0.0 8.8
10:36:24 md0 1 0.0 1 24 11.7 11.1
10:36:28 md0 0 0.0 0 16 0.0 9.5
10:36:32 md0 2 0.0 2 36 8.4 13.6
10:36:36 md0 1 0.0 1 16 10.9 16.1
Average md0 1 0.0 1 19 8.5 12.9

last pid: 8597; load averages: 0.36, 0.53, 0.74
10:47:45
181 processes: 179 sleeping, 2 on cpu
CPU states: 95.6% idle, 1.4% user, 2.8% kernel, 0.1% iowait, 0.0%
swap
Memory: 6144M real, 1303M free, 3097M swap in use, 3063M swap free

SunOS MachineA 5.8 Generic_117350-25 sun4u 10/10/05
10:48:03 device %busy avque r+w/s blks/s avwait avserv
10:48:07 md0 4 0.1 3 99 11.4 13.3
10:48:11 md0 2 0.0 2 40 11.2 12.6
10:48:15 md0 1 0.0 0 8 17.5 12.7
10:48:19 md0 3 0.1 3 52 12.7 18.9
10:48:23 md0 2 0.0 1 28 10.0 13.5
Average md0 2 0.1 2 45 11.8 14.7

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