lkml.org 
[lkml]   [2010]   [Aug]   [9]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
SubjectRe: [PATCH 07/10] Increase compressed page size threshold
From
Hi Nitin,

On Mon, Aug 9, 2010 at 8:26 PM, Nitin Gupta <ngupta@vflare.org> wrote:
> Compression takes much more time than decompression. So, its quite
> wasteful in terms of both CPU cycles and memory usage to have a very
> low compressed page size threshold and thereby storing such not-so-well
> compressible pages as-is (uncompressed). So, increasing it from
> PAGE_SIZE/2 to PAGE_SIZE/8*7. A low threshold was useful when we had
> "backing swap" support where we could forward such pages to the backing
> device (applicable only when zram was used as swap disk).
>
> It is not yet configurable through sysfs but may be exported in future,
> along with threshold for average compression ratio.
>
> Signed-off-by: Nitin Gupta <ngupta@vflare.org>

The description makes sense but lacks any real data. What kind of
workloads did you test this with? Where does it help most? How much?

Pekka


\
 
 \ /
  Last update: 2010-08-09 20:35    [from the cache]
©2003-2014 Jasper Spaans. Advertise on this site