Stability and Memory Pressure in 8.2

[Gary C Martin]

On 10 Sep 2008, at 21:02, Michael Stone wrote:

> A more accurate test would be to disable the preloading itself rather
> than disabling isolation but leaving rainbow loading the libraries. :)

:-)

> To do that, see lines 31-32 of
>
>  /usr/lib/python2.5/site_packages/rainbow/service.py
>
> You want to set self.preloader_hint = False and comment out the call  
> to
> self.preload_common_modules() by putting '#' at the beginning.

OK, retested build 759 with above change, otherwise same test  
procedure as before:

All five Activities launched, free buffers/cache reports 186Mb, an  
increase of 15Mb relative to when the rainbow fork trick is active,  
and 7Mb less than when /etc/olpc-security is just roughly removed.  
Write-51 and Record-57 are still better off without the rainbow trick,  
with Calculate-23, Paint-22, and Moon-4 gaining a slight memory  
benefit from the fork trick.

(By the way the % figures shown are the %MEM as reported by top)

Write-57
trick -> 15.5% (RES=35m, SHR=13m, DATA=20m)
no trick -> 13.5% (RES=31m, SHR=11m, DATA=18m)

Record-57
trick -> 14.2% (RES=32m, SHR=14m, DATA=64m)
no trick -> 11.4% (RES=26m, SHR=12m, DATA=62m)

Calculate-23
trick -> 10.6% (RES=24m, SHR=8m, DATA=15m)
no trick -> 11% (RES=25m, SHR=11m, DATA=13m)

Paint-22
trick -> 10.1% (RES=23m, SHR=8m, DATA=14m)
no trick -> 10.4% (RES=23m, SHR=11m, DATA=11m)

Moon-4
trick -> 9.7% (RES=22m, SHR=8m, DATA=13m)
no trick -> 10.4% (RES=23m, SHR=11m, DATA=11m)

/usr/bin/X
trick -> 7.5% (RES=17m, SHR=13m, DATA=9m)
no trick -> 5.6% (RES=12m, SHR=9m, DATA=9m)

Any more for any more?

BTW: I still haven't spotted where the overall (~15Mb in this case)  
savings of the rainbow fork trick are coming from.

--Gary