Re: 2.4.17-pre2+ext3-0.9.16+anton's cache aligned smp

[Daniel Phillips]

On December 6, 2001 09:45 am, Andrew Morton wrote:
> Yusuf Goolamabbas wrote:
> > 
> > Running 2.4.17-pre2 + ext3-0.9.16 + Anton Blanchards
> > cacheline_aligned_smp patch available at
> > 
> > http://samba.org/~anton/linux/cacheline_aligned/
> 
> omigod look at that graph.
> 
> Excuse me while I get frustrated.  Will someone *please* send that
> damn patch to [e-mail]?
> 
> (It can be improved further by putting padding *behind* the lock
> but hey).
> 
> > ...
> > 
> > With Anton's patch, the number of ctx-swtch/sec drops by around 3000
> > from avg of 9000 (for 17-pre2+ext3) to avg of 6000 (with anton) as seen
> > by vmstat 1
> 
> Really?  The spinlock cacheline alignment alone made that
> difference?  I wonder why.

Before getting *too* excited, remember, it's dbench, so effects could easily 
be magnified.  Maybe test with something better behaved?

--
Daniel