lkml.org 
[lkml]   [2006]   [Jan]   [1]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH 6/9] clockpro-clockpro.patch
From
Date
On Sat, 2005-12-31 at 20:40 -0200, Marcelo Tosatti wrote:
> On Fri, Dec 30, 2005 at 11:43:34PM +0100, Peter Zijlstra wrote:
> >
> > From: Peter Zijlstra <a.p.zijlstra@chello.nl>
>
> Peter,
>
> I tried your "scan-shared.c" proggy which loops over 140M of a file
> using mmap (on a 128MB box). The number of loops was configured to "5".
>
> The amount of major/minor pagefaults was exactly the same between
> vanilla and clockpro, isnt the clockpro algorithm supposed to be
> superior than LRU in such "sequential scan of MEMSIZE+1" cases?

yes it should, hmm, have to look at that then.

What should happen is that nr_cold_target should drop to the bare
minimum, which effectivly pins all hot pages and only rotates the few
cold pages.

> Oh well, to be sincere, I still haven't understood what makes CLOCK-Pro
> use inter reference distance instead of recency, given that its a simple
> CLOCK using reference bits (but with three clocks instead of one).
>
> But thats probably just my ignorance, need to study more.

The reuse distance is in PG_test. Please see the clockpro-documentation
patch, which should explain this. If its still not clear after that let
me know, I'll be more verbose then.

--
Peter Zijlstra <a.p.zijlstra@chello.nl>

-
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: 2006-01-01 11:42    [W:0.118 / U:6.836 seconds]
©2003-2017 Jasper Spaans. hosted at Digital OceanAdvertise on this site