Experiences with RELENG_7

[Kris Kennaway]

Roland Smith wrote:
> On Sun, Oct 28, 2007 at 01:44:21AM +0200, Kris Kennaway wrote:
>> Roland Smith wrote:
>>> Hovewer, sometimes a program seems to hog the CPU for a couple of
>>> seconds (as seen in top(1))
>> Can you please explain (with supporting paste of command output) what you 
>> mean by this?
> 
> I'll save some top output next time. But what happened was this; all of
> a sudden the mouse pointer started moving erratically, and the music
> playing in audacious started skipping. All other X programs started
> responding erratically as well. It looked like the X server wasn't
> getting any CPU time. After starting top in a terminal I saw that telak
> was at 99% WCPU. That is odd, because it's job is to keep a couple of
> pictures on the X root window updated every minute. I've used the same
> port (same version even) on 6-STABLE with SCHED_4BSD without these
> symptoms. It is started from my ~/.xinitrc.
> 
> After killing telak, the situation returned to normal. I restarted
> telak, and a couple of hours later it happened again.

Sounds like the issue is that telak is misbehaving.  The scheduler will 
not cause it to suddenly chew up CPU when it should be sleeping.

> It also happened with cc1 when I was compiling a port. In that case the
> situation returned to normal when that particular instance was
> finished. That compilation was running in a terminal window that was
> iconified at the time.

This may be unrelated.  The new version of gcc has higher memory 
requirements, and it is common for it to access swap during compilation 
when the system is also busy running other tasks.  If you see it 
happening with cc again, make sure to check this.

> In case I forgot to mention it, I deleted and recompiled all ports after
> the 6->7 update to make sure there was no old cruft lying around. I am
> running a custom kernel because I'm using GEOM_ELI. Do you need to see
> my kernel config?

What are you using GELI for?  If it's encrypting data used by those 
processes that will of course add to the load.

Kris