lkml.org 
[lkml]   [2007]   [Sep]   [5]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: tbench regression - Why process scheduler has impact on tbench and why small per-cpu slab (SLUB) cache creates the scenario?
On Wed, 5 Sep 2007, Zhang, Yanmin wrote:

> > > However, the approach treats the slabs in the same policy. Could we
> > > implement a per-slab specific approach like direct b)?
> >
> > I am not sure what you mean by same policy. Same configuration for all
> > slabs?
> Yes.

Ok. I could add the ability to specify parameters for some slabs.

> > Would it be possible to try the two other approaches that I suggested? I
> > think both of those may also solve the issue. Try booting with
> > slab_max_order=0
> 1) I tried slab_max_order=0 and the regression becomes 12.5%. It's still
> not good.
>
> 2) I apllied patch
> slub-direct-pass-through-of-page-size-or-higher-kmalloc.patch to kernel
> 2.6.23-rc4. The new testing result is much better, only 1% less than
> 2.6.22.

Ok. That seems to indicate that we should improve the alloc path in the
page allocator. The page allocator performance needs to be competitive on
page sized allocations. The problem will be largely going away when we
merge the pass through patch in 2.6.24.
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2007-09-05 12:49    [W:0.122 / U:0.120 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site