[sugar] prefork hack and memory usage

[Tomeu Vizoso]

Hi,

today did some quick experiments in order to see if preforking gives
us any improvements regarding memory usage. I launched 5 instances of
a very simple pygtk activity
(http://dev.laptop.org/git?p=users/marco/edit-activity;a=summary) and
executed 'free' before and after, along with ps_mem.py.

I would like to do more interesting experiments in the near future
(different activities, etc), but any comments about this data will be
appreciated. From my unexperienced look, we are saving around 3.8MB
per instance.

http://www.pixelbeat.org/scripts/ps_mem.py

Normal:
             total       used       free     shared    buffers     cached
Mem:        237836     183240      54596          0          0      79420
-/+ buffers/cache:     103820     134016

  8.6 MiB +  10.3 MiB =  18.9 MiB       Edit <db74d9451
  9.0 MiB +  10.4 MiB =  19.4 MiB       Edit <f28c569d2
  9.0 MiB +  10.4 MiB =  19.4 MiB       Edit <f6f10dcc6
  9.0 MiB +  10.4 MiB =  19.4 MiB       Edit <f0b1f10b7
  9.0 MiB +  10.4 MiB =  19.4 MiB       Edit <672d9cb6f

             total       used       free     shared    buffers     cached
Mem:        237836     228948       8888          0          0      81940
-/+ buffers/cache:     147008      90828


Preforking:
             total       used       free     shared    buffers     cached
Mem:        237836     183396      54440          0          0      80324
-/+ buffers/cache:     103072     134764

  4.4 MiB +  13.7 MiB =  18.0 MiB       Edit <040689fe6
  4.8 MiB +  13.8 MiB =  18.6 MiB       Edit <e97d30e3a
  4.8 MiB +  13.8 MiB =  18.6 MiB       Edit <0d80eebf8
  4.9 MiB +  13.8 MiB =  18.6 MiB       Edit <ceff1fd08
  4.9 MiB +  13.8 MiB =  18.6 MiB       Edit <dd5d72fb3

             total       used       free     shared    buffers     cached
Mem:        237836     208924      28912          0          0      80780
-/+ buffers/cache:     128144     109692


Thanks,

Tomeu