lkml.org 
[lkml]   [2007]   [Oct]   [1]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [15/17] SLUB: Support virtual fallback via SLAB_VFALLBACK
On Fri, 28 Sep 2007, Mel Gorman wrote:

> Minimally, SLUB by default should continue to use order-0 pages. Peter has
> managed to bust order-1 pages with mem=128MB. Admittedly, it was a really
> hostile workload but the point remains. It was artifically worked around
> with min_free_kbytes (value set based on pageblock_order, could also have
> been artifically worked around by dropping pageblock_order) and he eventually
> caused order-0 failures so the workload is pretty damn hostile to everything.

SLAB default is order 1 so is SLUB default upstream.

SLAB does runtime detection of the amount of memory and configures the max
order correspondingly:

from mm/slab.c:

/*
* Fragmentation resistance on low memory - only use bigger
* page orders on machines with more than 32MB of memory.
*/
if (num_physpages > (32 << 20) >> PAGE_SHIFT)
slab_break_gfp_order = BREAK_GFP_ORDER_HI;

We could duplicate something like that for SLUB.


-
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: 2007-10-01 23:13    [from the cache]
©2003-2011 Jasper Spaans