Re: Locking comment on shrink_caches()

Vojtech Pavlik
2001-09-27T01:34:10Z

On Thu, Sep 27, 2001 at 03:29:27AM +0200, Trond Eivind Glomsr?d wrote:

> Vojtech Pavlik <vojtech@suse.cz> writes:
>
> > On Wed, Sep 26, 2001 at 10:20:21PM +0200, Vojtech Pavlik wrote:
> >
> > > > generic Athlon is
> > > >
> > > > nothing: 11 cycles
> > > > locked add: 11 cycles
> > > > cpuid: 64 cycles
> > >
> > > Interestingly enough, my TBird 1.1G insist on cpuid being somewhat
> > > slower:
> > >
> > > nothing: 11 cycles
> > > locked add: 11 cycles
> > > cpuid: 87 cycles
> >
> > Oops, this is indeed just a difference in compiler options.
>
> No, it's not:
>
> [teg@xyzzy teg]$ ./t
> nothing: 11 cycles
> locked add: 11 cycles
> cpuid: 64 cycles
> [teg@xyzzy teg]$ ./t
> nothing: 11 cycles
> locked add: 11 cycles
> cpuid: 64 cycles
> [teg@xyzzy teg]$
> [teg@xyzzy teg]$ ./t
> nothing: 11 cycles
> locked add: 11 cycles
> cpuid: 87 cycles
> [teg@xyzzy teg]$ ./t
> nothing: 11 cycles
> locked add: 11 cycles
> cpuid: 87 cycles
> [teg@xyzzy teg]$ ./t
> nothing: 11 cycles
> locked add: 11 cycles
> cpuid: 64 cycles

Interesting: Try while true; do t; done and watch it change between 64
and 87 every 2.5 seconds ... :)

--
Vojtech Pavlik
SuSE Labs