2010/11/18 Bruce Cran <bruce@cran.org.uk>:
>Have you tried increasing kern.sched.preempt_thresh? According to
>http://groups.google.com/group/mailing.freebsd.stable/browse_thread/thread/05a39f816fd8acc6/82affa9f195b747d?lnk=raot&fwc=1&pli=1
>a good value for desktop use would be 224.
Hmm, I though I tried this -- but this helps indeed. :-)
The browser, movie player etc. behave much better when a "make -j4
buildworld" is running on my 2-core machine in the background. Thank
you.
2010/11/18 Bruce Cran <bruce@cran.org.uk>:
> If you're using UFS, I've found it to be quite a bottleneck when
> doing parallel IO: I even ran a "svn up" in one terminal and tried to
> login on another a couple of days ago only to find the motd took over 5
> seconds to appear! That may be excessive since I was running a kernel
> with WITNESS and INVARIANTS, but I've found ZFS to be far better if you
> want good interactivity when reading/writing to disks.
This is indeed another issue, which I also encountered, but explicitly
left out since I don't blame the task scheduler for that. ;)
Unfortunately, I don't know how much SCHED_ULE's inability to cope
with more runnable threads than cores, as Steve mentioned, accounts to
the problem I observe. Time to switch back to SCHED_4BSD? *sigh*
Lucius