En la página de iostat
manual he encontrado estas dos columnas similares:
await
The average time (in milliseconds) for I/O requests issued to the device to be served. This
includes the time spent by the requests in queue and the time spent servicing them.
svctm
The average service time (in milliseconds) for I/O requests that were issued to the device.
Warning! Do not trust this field any more. This field will be removed in a future sysstat
version.
¿Estas columnas están destinadas a representar lo mismo? Parece que a veces están de acuerdo, pero a veces no:
avg-cpu: %user %nice %system %iowait %steal %idle
4.44 0.02 1.00 0.36 0.00 94.19
Device: rrqm/s wrqm/s r/s w/s rkB/s wkB/s avgrq-sz avgqu-sz await r_await w_await svctm %util
sda 0.07 0.96 0.28 1.28 8.98 47.45 72.13 0.02 11.36 11.49 11.34 5.71 0.89
avg-cpu: %user %nice %system %iowait %steal %idle
8.00 0.00 2.50 2.50 0.00 87.00
Device: rrqm/s wrqm/s r/s w/s rkB/s wkB/s avgrq-sz avgqu-sz await r_await w_await svctm %util
sda 0.00 9.00 2.00 6.00 12.00 68.00 20.00 0.05 6.00 2.00 7.33 6.00 4.80
avg-cpu: %user %nice %system %iowait %steal %idle
4.57 0.00 0.51 0.00 0.00 94.92
Device: rrqm/s wrqm/s r/s w/s rkB/s wkB/s avgrq-sz avgqu-sz await r_await w_await svctm %util
sda 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
avg-cpu: %user %nice %system %iowait %steal %idle
13.93 0.00 1.99 1.49 0.00 82.59
Device: rrqm/s wrqm/s r/s w/s rkB/s wkB/s avgrq-sz avgqu-sz await r_await w_await svctm %util
sda 0.00 29.00 0.00 4.00 0.00 132.00 66.00 0.03 7.00 0.00 7.00 7.00 2.80
Además de la advertencia obvia que svctm
se deprecia, ¿cuál es la diferencia entre estas dos columnas ?
await
=svctm
+however_long_in_queue
, tal como dice el excelente manual!