Why so slow? Why so memory-hungry?

[Kent Slimm]

I'm running the latest version of Firefox (80.0.1) on Windows 10 on a new computer with a fast processor and 8 MB of RAM. Yet browsing is often quite slow -- much slower than on Chrome -- and Task Manager shows that Firefox alone routinely uses 3.5-5 GB of memory. (Even writing this message is frustrating; I have to keep stopping and waiting for it to catch up.) At the moment I have 9 tabs open, most of them sites that don't auto-update. And no video. I find myself closing out of Firefox and restarting it periodically, which helps for awhile but is annoying.

Is it just me or is there a systemic problem here?

[LIMPET235]

Hello,
Well, we always suggest the following as a 1st thing to try...
Have you tried running in Firefox' Safe Mode yet?
Might be due to an extension or ?
ref; > http://kb.mozillazine.org/Safe_Mode

&...I'm sure that you meant that you have 8 Gigs of RAM.

[Kent Slimm]

Thanks for the quick reply. And, yes, I meant 8 GB of RAM. (Sorry about that.)

I wanted to get a sense of whether others are experiencing this same drain on memory and slow performance that I'm reporting before I assume the problem is only on my machine and then going through all the Safe Mode troubleshooting. FWIW, I use no themes and just four add-ons: Disconnect, LastPass (password manager), uBlock Origin, and Minimal Twitter. The first three are so popular and frequently updated that it's hard to imagine they'd be hogging memory. The last is very limited in scope; it just cleans up the Twitter interface.

Wouldn't the fact that things temporarily improve after I've restarted Firefox suggest that it's leaking memory? And this is what umpteen previous releases have claimed to improve.

[LIMPET235]

Firefox' Safe Mode does more than just disable the extensions.


NB: Be careful of the "Delete all bookmarks except for back-ups" option.

Don't add any extensions or themes until it's working O.K.
If Firefox is O.K. in Safe Mode then it's possibly an extension/theme...etc causing it.
Run Firefox in normal mode & disable them all. Re-start Firefox.
Enable each in turn, or by ½'s, re-starting Firefox each time, till the faulty extension is found.
Either update or un-install it.

See this incomplete list,
> http://kb.mozillazine.org/Problematic_extensions

When in Safe Mode...
* The status of plug-ins is not affected.
* Custom preferences are not affected.
* All extensions are disabled.
* The default theme is used, without a persona.
* userChrome.css and userContent.css are ignored.
* The JIT/Javascript compiler is disabled.
* The default toolbar layout is used.
* Hardware acceleration is disabled.

[skuddle]

I have a similar problem. I also have Bitdefender installed along with NoScript.

I'm too lazy at the moment to fiddle around trying to get Firefox (and a couple other apps as well) to load faster. I suspect there's a chance that one, or both, of those apps is the cause of the problem.

[Kent Slimm]

I just checked Firefox's own task manager and learned that all my plug-ins and open tabs *combined* use about 150 MB of memory, whereas Windows task manager shows me that Firefox overall is consistently using at least 20-30 times that amount (3.5-5.0 GB). It's infuriating even to write this message; after every few words, it stops and I have to wait until it's able to record my typing again. (I finally gave up, composed the rest of the message elsewhere and pasted it in.)

While you say that Safe Mode does more than block themes (of which I have none) and add-ons, your recommendation following the restart seems to assume that the problem is with the add-ons, which I think is unlikely in my case. I mean, if it's some other process or feature of Firefox that's slowing things down, how does a Safe Mode test help me if I don't plan to stay in that mode permanently?

Again, I'm not experiencing this memory drain in Chrome or in other programs.

@skuddle: Until last week I, too, had been using BitDefender, which I thought might be at fault. I uninstalled it and switched to Windows 10's native security program. No difference.

[RobertJ]

While you say that Safe Mode does more than block themes (of which I have none) and add-ons, your recommendation following the restart seems to assume that the problem is with the add-ons,

Not what was said.

how does a Safe Mode test help me if I don't plan to stay in that mode permanently?

It is the first step to debug your issue. Try it only takes a minute.

.

[skuddle]

>>@skuddle: Until last week I, too, had been using BitDefender, which I thought might be at fault. I uninstalled it and switched to Windows 10's native security program. No difference.<<

Thanks. I appreciate your reply and info. Hope we can find out what's happening here.

[Kent Slimm]

Update: Before trying Safe mode, I restarted Firefox in regular mode. Its memory use, according to Windows Task Manager, promptly dropped from 3.5-5.0 GB to 600 MB. (If I had done this in Safe mode, I would have attributed the drastic reduction to that!) After an hour of moderate (non-video) browsing, it climbed back to 1.4 GB. After another few hours -- same number of tabs open, same (limited) number of add-ons -- it was at 2.4 GB. Before long I expect it to be back to using so much memory that I experience slower performance again. (Point of reference: Chrome has stayed steady at ~ 350 MB this whole time.)

I suppose it's possible that memory use would have dropped a little more if I had restarted in Safe mode -- or would have taken a little longer to climb back up -- and I may yet try that experiment. (It's a bit of a pain for me to keep restarting because, for privacy reasons, I set my browsers to delete all cookies on restart.) But I'm doubtful that it will help much and in any case using Safe mode long term isn't feasible for me.

Isn't what I'm experiencing -- and I have to assume it's not just me -- called "memory leak"? Do the engineers working on updates know how bad it's gotten?

[tanstaafl]

Nobody is suggesting using safe mode as a long term solution, its just a way to determine if Firefox or an add-on is the culprit.

If the memory use didn't grow to several GB using safe mode then one of your add-ons (not Firefox) has a memory leak. Start Firefox in regular mode, but with one add-on disabled. See if the problem returns. If it doesn't re-enable the add-on and chose another one. Repeat until you isolated the culprit.

Alternatively pick the most complex add-on and uninstall all the others. Run in regular mode and see if the problem occurs. If it doesn't add another add-on, repeat...

[therube]

(Point of reference: Chrome has stayed steady at ~ 350 MB this whole time.)

Not so.
Open Chrome up, fresh, to a blank page, & it's probably using ~300 MB.
Then open up yahoo.com. Now you're likely ~600 MB.

Open new, clean instances of both browsers.
Throw one to the left side of your screen. Throw the other to the right side of your screen.
Duplicate actions, sites visited... in one to the other.

After a period of browsing, what are the memory usage numbers of each?


From what I have found, once a browser - any browser starts eating higher amounts of RAM, performance suffers, period. Where this happens & to what extent may differ, but they all suffer, and will differ (seemingly) by OS & system configurations.

On Windows x64, in general, once you get > ~4 GB of RAM, I'd think you'd see performance degradation.

Other then RAM, keep an eye on CPU usage. Also note that something as silly as an animated gif (or webpage background, or miner, or...) could be negatively affecting performance.

[Kent Slimm]

@therube: I certainly agree with you that performance will suffer on any browser when it starts using that amount of RAM.

But I can tell you that, at least on my machine, Chrome does not do so -- even after many days of varied use and even with roughly the same number of tabs open and roughly the same number of add-ons/extensions as Firefox (and, in fact, several of the *same* add-ons). I just checked again and Chrome's memory is using 215 MB, vs. Firefox's (which I restarted just a few days ago) 3200 MB. You, of course, may have a different experience, but I'm telling you what mine is ... and it reflects Chrome after lengthy use, not freshly opened.

[RobertJ]

.
IT IS ONE OF YOUR ADD-ONS!!

Figure which one and delete it.

I have NO problem with FF80.0.1 and 15 add-ons.

.

[Frank Lion]

I just checked again and Chrome's memory is using 215 MB.

No, it's not.

You need to learn how to read all of the Chrome processes either in Windows Task Manager or in the Chrome Task Manager.

You, of course, may have a different experience, but I'm telling you what mine is ... and it reflects Chrome after lengthy us

You're telling us what you think yours is. Some of us do also use the Chrome browser, you know.

[Kent Slimm]

.
IT IS ONE OF YOUR ADD-ONS!!

Figure which one and delete it.

I have NO problem with FF80.0.1 and 15 add-ons.

.

I use only four add-ons. Disconnect ("make the web faster...") and uBlock Origin ("easy on CPU & memory") are not only enormously popular and frequently updated but are said to *reduce* memory use by blocking trackers, ads, and whatnot. The third, also well-known, is the password manager LastPass. And the last, Minimal Twitter, just simplifies the UI on a single site and, according to Firefox Task Manager, uses only 300 KB [not a typo].

I'm not trying to be difficult here, and I really appreciate the advice. But does it really seem likely that one of these add-ons explains why Ff regularly expands its memory use from <1GB to 3.5 GB following a restart after a few hours of moderate use?