[sugar] Memory pressure (Re: Signed candidate-765 and gg-765-2 builds available for testing.)

[Marco Pesenti Gritti]

Since everyone major concern is memory pressure especially with
Browse, I did some comparison tests with Update.1. The results are
somewhat surprising:

os711 + g1g1 activity pack

Startup: free 127 mb
Min Browse: free 91 mb
Max Browse: free 61 mb

gg-765-2

Startup: free 129 mb
Min Browse: free 91 mb
Max Browse: free 63 mb

Notes:

* I have not repeated the tests yet (I intend to do so), so there is
the possibility of measurement errors. From my experience so far I'd
say +/- 5 mb.
* Free memory is measured with free, after having dropped the caches
with echo 3 >/proc/sys/vm/drop_caches
* Min Browse is free memory just after having started browse, no navigation.
* Max Browse is the maximum amount of memory I could get Browse to use
while navigating randomly inside wikipedia (starting from Moon).
Browse memory usage normally grows up quickly when you load the first
few pages and then it stabilizes and does not grow anymore.
* I tested on clean copy-nand installations of both images, without any reboot.

Marco