Re: [QUICKLIST 0/6] Arch independent quicklists V1

[Andrew Morton <akpm@linux-foundation.org>]

> On Mon, 12 Mar 2007 19:32:11 -0700 (PDT) David Miller <davem@davemloft.net> wrote:
> From: David Miller <davem@davemloft.net>
> Date: Mon, 12 Mar 2007 19:26:16 -0700 (PDT)
> 
> > From: Paul Mackerras <paulus@samba.org>
> > Date: Tue, 13 Mar 2007 11:37:32 +1100
> > 
> > > David Miller writes:
> > > 
> > > > I ported this to sparc64 as per the patch below, tested on
> > > > UP SunBlade1500 and 24 cpu Niagara T1000.
> > > 
> > > Did you see any performance improvement?  We used to have quicklists
> > > on ppc, but I remain to be convinced that they actually help.
> > 
> > It shaved about 3 or 4 seconds consistently off of my kernel
> > build on Niagara which usually clocks in just over 4 minutes
> > on this 24 thread machine.
> 
> I want to quantify this with the fact that all the cache false sharing
> issues are irrelevant in this test because the L2 cache is shared
> between all of the cpu threads on Niagara.
> 
> It was fast just because the quicklists were lighter weight than the
> SLAB stuff.

So...  what would happen if sparc64 were to use neither quicklists nor
slab?  Just grab these pages from the page allocator and clear them?