Re: DragonFly-2.3.0.864.gc5b83 master sys/platform/pc32/apic mpapic.c sys/platform/pc32/isa clock.c sys/platform/pc64/isa clock.c sys/platform/vkernel/platform systimer.c sys/sys systimer.h

[Hasso Tepper <hasso@xxxxxxxxx>]

Matthew Dillon wrote:
> I think you can enable the lapic timer by default in a few days, or
> even now.  I'm running it on my test boxes and will report any issues
> but it appears to be solid as a rock.

It's not so simple. There is a problem when using deep sleep states in 
modern CPU's (C3 and deeper) - lapic timer is stopped when CPU enters 
into C3. And using C3 (or even C4) is obviously completely normal thing 
to do in laptops.

See these commits for more pointers/details:

http://permalink.gmane.org/gmane.os.freebsd.devel.cvs.src/105079
http://lists.xensource.com/archives/html/xen-changelog/2008-05/msg00221.html
http://bugzilla.kernel.org/show_bug.cgi?id=2560


-- 
Hasso Tepper