Re: [9fans] Interrupt saturation

[erik quanstrom <quanstro@quanstro.net>]

On Sun Feb 28 04:57:09 EST 2010, lucio@proxima.alt.za wrote:
> The workstation I'm using presently seems to trigger as many
> interrupts as stats(1) can display, while the syscall graph is also
> extremely busy.
>
> I presume this is anomalous.  Killing the single instance of
> timesync(1) does not seem to make any difference at all.
>
> Any suggestions to where I should look?  I'm not running anything that
> would make me suspicious, but I'm going to restart the system just to
> check.

the exact number would be interesting.  i've added a field
to '#P/irqalloc' on my kernels that is the count of interrupts
per vector:

; cat '#P/irqalloc'
          3           0                    0 debugpt
          7           0                    0 mathemu
          8           0                    0 doublefault
          9           0                    0 mathover
         14           0                    0 fault386
         15           0                    0 unexpected
         16           0                    0 matherror
         50          18          18822033321 clock
         51          19                    0 lapicerror
         63          31                    0 lapicspurious
         65           1                    2 kbd
         73           9            772061679 ether0
         81          10              8689592 ether1
         89          11             11583013 ether2
         97           4                 5092 COM1
        105          14                    5 sdC (ata)

perhaps this would be useful.  you can pick it out
of ftp://ftp.quanstro.net/other/kernel.mkfs.bz2
in pc/trap.c.

- erik