Comment 248 for bug 187313

On 2009-02-11 17:47, Benjamin Geer wrote :
> Alexander, what's your definition of a "slow system"?
Memory is the most important.
I bought 2 bargain Tecra 8000 with 256 KB max for kids to run Xfce4.
I finally found that Gnome could run too @400 MHz up to some limit.
Firefox makes the highest memory usage and is the limit.
(no other program I use, eg Gimp, is such a bottleneck)
FF seems to overuse (probably fragment) virtual memory over time.
When that happens, thrashing starts.
Thrashing is page swapping preventing normal use of the CPU.
It can last from a few to sometimes 15 seconds or even more.
If Firefox is stopped/restarted, it runs fast for some more time.
(I mean restarting the same pages, of course)

In contrast, I used a 512 MB 850 MHz WITHOUT SWAP for some time.
Even Firefox would run very decently in that config.
Which, of course, is thrashing-free.

When thrashing occurs, the mouse movements are jerky.
Mouse management seems to be slowed down.

So, if you want to make yourself a slow system...
Boot with mem=256M on the kernel command.