Re: cvs commit: src/sys/kern kern_spinlock.c src/sys/platform/vkernel/i386 cpu_regs.c src/sys/sys systm.h src/sys/platform/pc32/i386 machdep.c

[Matthew Dillon <dillon@xxxxxxxxxxxxxxxxxxxx>]

:Very nice.  I've been meaning to do this.  We could use monitor/mwait on core2duo CPUs for power reduction for example (also when waiting for the mplock/scheduler changes in the idle loop).
:
:cheers
:  simon

    I totally forgot about monitor/mwait, that's a very good idea.

    I put in these calls mainly so a virtual kernel does not completely
    destroy the performance the real kernel it is running under by spinning.

    The virtual kernel is not the most efficient thing in the world with
    all the MP lock contention we have, but even so it's not half bad!

    Another thing we can do is use the usched_set() system call (which needs
    documentation by the way!) to map each of the virtual kernel's cpus
    onto particular real-kernel cpus, instead of letting them float like
    they do now.  I dunno if that would improve performance at all though.

					-Matt
					Matthew Dillon 
					<dillon@backplane.com>