Bug#584495: iceweasel: Iceweasel terribly sluggish

[Mike Hommey]

On Thu, Jun 03, 2010 at 07:49:59PM -0400, Stefan Monnier wrote:
> Package: iceweasel
> Version: 3.5.9-3
> Severity: normal
> 
> For a couple months now maybe, I've noticed that Iceweasel is very sluggish.
> The slowness seems to be local (i.e. unrelated to the speed of connection) and
> manifests itself for example when moving the mouse horizontally across the
> menubar, where the redraw of the menus has trouble keeping up with the mouse
> movement, or when switching from one tab to another, where there's a clear
> delay and I get to see the tab being redrawn about 0.5s-1s before the actual
> windo's content.
> 
> This is on a 2.4GHz Althon X2 with 4GB of RAM, so it's not due to swapping, nor
> to the machine being particularly slow.
> The X server is using `nv', so it's not super fast, but it's been quite
> sufficient until now and doesn't seem to justify this sluggishness.
> 
> It's even worse if I try to display from the same machine on some other
> machine's Xserver (a Thinkpad X201s laptop on the same 54Mb/s wifi network):
> such remote connection is completely unusable for iceweasel, whereas I've used
> such remote display in the past (maybe a year ago) where the slowdown was very
> acceptable.
> 
> I have tried "iceweasel -no-remote -P" and run with a brand new profile, and
> have also tried with "iceweasel -safe-mode", but they still suffer from the
> sluggish display.
> 
> The odd thing about it is that I use very similar Debian installs on many
> machines and don't notice this slowdown on all machines.  Also I've noticed it
> at times on one machine, and then a week later it seemed to have disappeared.
> So I feel like maybe it has something to do with the underlying libraries (poor
> performance when some libraries and iceweasel are not upgraded at the same
> time, maybe?).
> 
> I have not reported it until now specifically because it seemed somewhat
> transient, and because I cannot really point to something very specific about
> the sluggishness.  But since the problem seems to still be around, and since I
> recently noticed that the remote display is *really* slow, I felt it was time
> (and important) to report it.

Did you try disabling plugins, too? Did you give a try to the version in
experimental?

Mike