How long ago was this? There's been a number of memory usage improvements since 3.5.

I had 40 tabs open for the better part of last week and didn't notice a performance hit; and I've only got 2Gb RAM.

I have the latest version and my long running high count tab sessions slow down my system tremendously. OSX 8GB RAM.

I have memory-hemorrhaging problems under various versions of Windows as well. I need to restart at least once a day (I typically have ~8 tabs in use).

But the clincher that made me switch to Chrome a couple weeks ago was that every couple of hours it would decide of its own accord to tear off a tab into a new window, and then hang. This solved the memory leakage, but not in a useful way.

I'm pretty sure that my problems are related to badly-behaving addins. But Firefox doesn't provide any good way to troubleshoot addins (compare to Chrome), and it seemed to me that the process to track down the culprit given that the problem is nondeterministic and takes a couple of hours to manifest would be more difficult than the switch to Chrome.

That said, I'm having some compatibility problems with Chrome. Like, last night the CAPTCHA in the free annual credit report site wouldn't work.

Yeah. I had the same problem with chrome as well. Same setup. Maybe web browsers can't handle how I work with them at the moment. Maybe I'll go down the rabbit hole and try to fix some of the bugs myself.

Earlier this year. Can't remember exactly when. OSX.

I'm running Firefox 7.01 on a 4 year old machine with Ubuntu 11.04. I routinely have 30+ tabs open an never had a problem with speed. Maybe your friend's computer has other woes

These "I have X tabs open" comparisons are very unhelpful. Different sites take hugely different amounts of memory in just the same way that different desktop applications do.

If you want to make a even-slightly quantitative comparison you need to at least start by loading the same set of sites. Then you need to worry about them sending different content (e.g. different adverts) to different browsers.

In the end most people go by metrics like "how responsive does the UI feel", which is fine, although since it's a perception thing it can be influenced by factors other than the actual speed e.g. preconceived notions set by marketing.

Also, the browser plugins in use (e.g. adobe acrobat) have a huge impact.

I have a different problem. Firefox now aggressively trims memory usage - over-aggressively trims it, to the point that switching tabs incurs a 0.5 second pause as it reallocates memory it had thrown away. This is Firefox 7, and is most noticeable in image-heavy websites.

This is just discarding of decoded images; the issue there is not reallocating but having to redecode the image...

There is work ongoing to limit the redecoding to only the things that are visible in the viewport to alleviate this problem.

QFT

Though it's having both IceWeasel and Chromium that's pigging my box.

But yes, with aggressive browsing habits, 4GB simply wasn't enough memory.

40 tabs is a pretty low count for me.

I've got an Asus EEEpc with 2GB of RAM and 4GB swap and I always have Firefox open with 80+ tabs in 4+ windows. After a week or so it'll get really slow when loading and would crash in a day or two if usage continued, so I just kill it and it reloads everything.

This "more than a few tabs" or "more than an hour or two" is craziness? What is your friend running?

See, the problem here is that I do that with Opera on my EEEpc too, except I only have a gig of ram, no swap, and I don't have to kill it every week.

Firefox just doesn't cut it.

Sure, that I'd believe.

What OS are you in? How long do you keep it running like this? Sounds good.

I'm using Fedora 15^, and I think Opera has been running for approximately 3 weeks right now (my current uptime).

^ with Awesome WM, not those gnome/unity/kde memory pigs ;)