FreeBSD support in SMP platform

[John Baldwin]

On Friday 02 July 2004 01:33 pm, Kevin A. Pieckiel wrote:
> On Fri, Jun 04, 2004 at 02:50:24PM -0400, John Baldwin wrote:
> > When a thread is made runnable the idle CPUs contest on sched_lock so
> > much that invariable one CPU ends up timing out on sched_lock and
> > panic'ing.  This will be fixed eventually but not in the near future.
>
> Obviously, this isn't considered a show stopper bug by the developers, but
> it does seem to be quite an egregious error IMO.  Afterall, multi-processor
> systems seem to be getting more commonplace, and especially with HTT
> getting its share of the market, I would think that in not too many years a
> system showing eight or more processors--virtual or otherwise--would be not
> unheard of.
>
> Why is fixing this such a low priority?  Is it a complicated fix, or simply
> a lack of hardware for testing?

The fix is not really complicated so much as largely mechanical and time 
consuming.  It also doesn't seem to kick in until at least 8 logical 
processors or so.  However, I don't think the fix will be very long in coming 
anyway.

-- 
John Baldwin <jhb at FreeBSD.org>  <><  http://www.FreeBSD.org/~jhb/
"Power Users Use the Power to Serve"  =  http://www.FreeBSD.org