interrupt threads CPU usage in FreeBSD 8.0

[Igor Sysoev]

On Tue, Nov 03, 2009 at 05:36:55PM +0100, Attilio Rao wrote:

> 2009/10/21 Igor Sysoev <is at rambler-co.ru>:
> > Hi,
> >
> > for some reason in 8.0 top always shows 0% CPU usage for intr kernel
> > process and active interrupt thread, "irq19 bge0" in my case.
> >
> > 8-0 RC1 top -PS:
> >
> > CPU 0: 27.8% user,  0.0% nice,  7.1% system,  0.0% interrupt, 65.0% idle
> > CPU 1:  3.0% user,  0.0% nice,  2.3% system,  7.1% interrupt, 87.6% idle
> >
> >  PID USERNAME     THR PRI NICE   SIZE    RES STATE   C   TIME   WCPU COMMAND
> >   11 root           2 171 ki31     0K    32K RUN     0 140.7H 152.54% idle
> > 61371 nobody         1  69  -10   384M   289M kqread  0 105:56 17.77% nginx
> > 61372 nobody         1  67  -10   384M   293M CPU0    0 106:15 16.99% nginx
> >   12 root          15 -60    -     0K   240K WAIT    0  54:50  0.00% intr
> >
> > 8.0 RC1 top -PSH:
> >
> >  PID USERNAME    PRI NICE   SIZE    RES STATE   C   TIME   WCPU COMMAND
> >   11 root        171 ki31     0K    32K RUN     1  71.5H 81.05% {idle: cpu1}
> >   11 root        171 ki31     0K    32K CPU0    0  69.3H 69.19% {idle: cpu0}
> > 61372 nobody       68  -10   384M   294M kqread  0 107:06 18.99% nginx
> > 61371 nobody       68  -10   384M   291M kqread  0 106:45 16.99% nginx
> >   12 root        -68    -     0K   240K WAIT    1  50:48  0.00% {irq19: bge0}
> >   17 root         44    -     0K    16K syncer  1   5:23  0.00% syncer
> >   12 root        -32    -     0K   240K WAIT    1   3:06  0.00% {swi4: clock}
> >
> > 7.2-STABLE top -PS:
> >
> > CPU 0:  9.0% user,  0.0% nice,  7.9% system,  9.0% interrupt, 74.1% idle
> > CPU 1: 23.3% user,  0.0% nice,  8.3% system,  0.0% interrupt, 68.4% idle
> >
> >  PID USERNAME  THR PRI NICE   SIZE    RES STATE   C   TIME   WCPU COMMAND
> >   12 root        1 171 ki31     0K    16K RUN     0 275.0H 83.59% idle: cpu0
> >   11 root        1 171 ki31     0K    16K RUN     1 264.2H 76.27% idle: cpu1
> > 16109 nobody      1  68  -10   376M   307M CPU0    1  28:05 21.97% nginx
> > 16110 nobody      1   4  -10   376M   316M RUN     0  28:05 20.17% nginx
> >   26 root        1 -68    -     0K    16K WAIT    0 902:39  6.69% irq19: bge0
> 
> How old is your 7.2-STABLE?

I saw this on 7.0-7.2. One of 7.2-S is, for example, from 2009.10.04.23.59.59.
I believe I saw the same CPU usage on FreeBSD-6 too.


-- 
Igor Sysoev
http://sysoev.ru/en/