identifying cause of Consistent High IO Wait on RHEL 5.8 server
I have an RHEL 5.8 server that has been experiencing high io wait times as queried via snmp, or displayed via top. The wait time is hovering in the 35-50% range.
I've tried using ps to look for processes that go into a 'D' state, by using a snippet like this:
for x in `seq 1 1 10`; do ps -eo state,pid,cmd | grep "^D"; echo "----"; sleep 5; done
which gives me the following processes as being in a D state -
I don't see anything unusual being written to the syslogd. /var/log/messages is about 4 mb, after 4 days of being written to.
I'm not sure where to go next with this. Can anyone suggest what to look for next?