Slow I/O on RHEL 7.2
We are encountering slow disk I/O on RHEL 7.2. The OSW sample output is below? The DB is on disk xvdd. Can you please confirm if the "iostats" output point to slow disk I/O? We are using ACFS on Oracle Virtual Box. What is the ideal value of "await" and "svctm" ?
zzz ***Mon Jun 27 12:49:09 EDT 2016
avg-cpu: %user %nice %system %iowait %steal %idle
5.06 0.00 1.30 0.00 0.26 93.38
Device: rrqm/s wrqm/s r/s w/s rkB/s wkB/s avgrq-sz avgqu-sz await r_await w_await svctm %util
xvda 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
xvdb 0.00 0.00 0.00 4.00 0.00 20.00 10.00 0.00 0.00 0.00 0.00 0.00 0.00
xvdc 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
xvdd 0.00 0.00 84.00 26.00 712.00 267.00 17.80 0.93 8.39 10.82 0.54 3.95 43.40
xvde 0.00 0.00 0.00 10.00 0.00 123.00 24.60 0.00 0.40 0.00 0.40 0.40 0.40
xvdf 0.00 0.00 2.00 3.00 1.00 46.50 19.00 0.00 0.40 0.50 0.33 0.40 0.20
xvdg 0.00 0.00 0.00 1.00 0.00 4.00 8.00 0.00 0.00 0.00 0.00 0.00 0.00
dm-0 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
dm-1 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
dm-2 0.00 0.00 0.00 4.00 0.00 20.00 10.00 0.00 0.00 0.00 0.00 0.00 0.00
dm-3 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
dm-4 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
dm-5 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
dm-6 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
dm-7 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