I hope they use a more up to date version of Chromium. Last time I checked a few months ago the newest version of Chromium in most Linux repositories was 18.x
I'm not sure which distribution you're using, but the version of Chromium in Debian 7
is currently 27.0.1453.93-1~deb7u1
, the version in Ubuntu 12.04
, the version in Ubuntu 13.04
, and the stable upstream
version is 27.0.1453.94
. While the version of Chromium in Ubuntu is a little old, the version in Debian is up-to-date, and neither is anywhere close to as old as you supposed. I'm sure the situation is similar in other GNU/Linux distributions.
In every machine I've used them on chrome consistantly uses far more memory than firefox, especially with many tabs. And recent versions of firefox don't really have the memory leak issues of old, if your firefox is truly "leaking" memory its likely nor normal behavior, perhaps an extension and/or plugin issue.
That has always been my experience as well. I am using Firefox 21 with 7 addons and it consistently uses less memory and CPU time than Chromium 27 without any addons when I have the same pages open, which typically numbers 8 or 9.