SCHED_4BSD: More than 1 process running on UP machine?

Astrodog astrodog at
Sat Jun 30 17:06:44 UTC 2007

On 6/30/07, Ulrich Spoerlein <uspoerlein at> wrote:
> Hi all,
> I upgraded to -CURRENT and am running with SCHED_BSD on an UP machine
> (where ULE has no advantage over BSD, right?)
> Anyway, I never noticed top(1) under 6.x reporting more than 1 running
> process, which is only natural, considering this is an UP machine. Under
> 7.x however, top(1) reports up to 7-8 running processes, depending on
> how much stuff is going on.
> Is top(1) lying, or is/was my assumption about UP wrong all along?

Keep in mind, technically speaking, on a  UP system, when top refreshes....
its the only running process, and  its using 100% of the CPU. ;)

top/uptime/etc all use a small period of time, I believe, and under UP, the
maximum number of running processes under top would be topsampletime /
min_slice - 1. A process waiting in the run queue is reported as "running"
as well, as I recall, in which case the number of "running" processes under
top would be, at most, the maximum size of the run queue.

Hopefully this is helpful (and correct), I haven't looked inside top in
quite awhile.

--- Harrison

> Ulrich Spoerlein
> PS: whats the new state 'ucond' all about?
> --
> "The trouble with the dictionary is you have to know how the word is
> spelled before you can look it up to see how it is spelled."
> -- Will Cuppy
> _______________________________________________
> freebsd-current at mailing list
> To unsubscribe, send any mail to "freebsd-current-unsubscribe at"

More information about the freebsd-current mailing list