no idle CPU ... system hogging it all ...

[Marc G. Fournier]

On Mon, 14 Apr 2003, David Schultz wrote:

> On Fri, Apr 11, 2003, Marc G. Fournier wrote:
> >
> > Its been looking like this pretty much all day ... top shows nothing
> > major, and the drive looks reaonably quiet ... there is nothing in
> > messages to indicate a problem that I can see (even those enclosure
> > messages have been reasonably quiet) ...
>
> You can profile the kernel to find out, although at this hour I
> probably can't recall all the necessary details.  I believe you
> need to say 'make buildkernel CONFIGARGS=-p', then use kgmon(8)
> and gprof(1) to extract and analyze the data.
>
> Based on the ps output you gave, it looks like vmdaemon and syncer
> are taking up most of the time.  This suggests that perhaps there
> is a hardware or driver problem with disk I/O.  Some drivers
> perform very small delays to wait for the hardware by spinning
> instead of eating the overhead of a context switch.  It could be
> that one of these drivers has a bug, or the hardware is taking
> longer than expected to respond.

That was/is kinda what I'm expecting ... so far, luck/experience with this
Adaptec 2120S controller hasn't been great :(  Scott got rid of the
TIMEOUT issue, but now the server hangs solid every few days to the point
that the keyboard is unresponsive to either a ctl-alt-esc or ctl-alt-del
:(