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One tab uses nearly a GB of RAM

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I'm trying to figure out why firefox keeps slowing down with time. Lately I've noticed that memory usage of firefox has skyrocketet - I end up with 3GB of RAM usage and the browser is slow after 15mins of use.

I've restarted firefox with addons disabled and it seems that is faster, but before I create a new profile and call it a day I would like to try to figure out what's causing all this.

I restarted firefox with disabled addons and this is the memory measurement: https://gist.github.com/compojoom/92e0b2ca8bab231d9cf4f7924dae540d

And this is with my normal installation with the following plugins 1password, Adblock Plus, RAMback https://gist.github.com/compojoom/61eb69f1619717d69b3645ceeeeef1b0

I don't know how to read the memory profiles and would be happy if someone could have a look and suggest what's screwed up?

The health report never shows a crash, but I have to constantly kill the firefox process as it keeps growing and growing and the browser becomes slow and unusable.

I'm trying to figure out why firefox keeps slowing down with time. Lately I've noticed that memory usage of firefox has skyrocketet - I end up with 3GB of RAM usage and the browser is slow after 15mins of use. I've restarted firefox with addons disabled and it seems that is faster, but before I create a new profile and call it a day I would like to try to figure out what's causing all this. I restarted firefox with disabled addons and this is the memory measurement: https://gist.github.com/compojoom/92e0b2ca8bab231d9cf4f7924dae540d And this is with my normal installation with the following plugins 1password, Adblock Plus, RAMback https://gist.github.com/compojoom/61eb69f1619717d69b3645ceeeeef1b0 I don't know how to read the memory profiles and would be happy if someone could have a look and suggest what's screwed up? The health report never shows a crash, but I have to constantly kill the firefox process as it keeps growing and growing and the browser becomes slow and unusable.

All Replies (6)

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I called for more help.

You are running a beta version of Firefox. This means there may be issues.

Have you tried running the current version 53?


More than one process is normal for the current Firefox. http://www.ghacks.net/2016/07/22/multi-process-firefox/

Multi-process Firefox is codenamed "e10s". https://wiki.mozilla.org/Firefox/multiprocess


Try to disable multi-process tabs in Firefox. You can disable multi-process tabs in Firefox by setting the related prefs to false on the about:config page.

browser.tabs.remote.autostart = false browser.tabs.remote.autostart.2 = false

http://www.ghacks.net/2016/07/22/multi-process-firefox/

Type about:config<enter> in the address bar. If a warning screen comes up, press the Be Careful button. At the top of the screen is a search bar.

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Yes, I'm using Firefox Developer Edition. I now started the normal Firefox in v53 and it does the same thing.

Here is the memory usage: https://gist.github.com/compojoom/ac3a63a9c0de31516e651453a9e83dc7

I'm not running multi-process tabs as Firefox has disabled this due to incompatible addons, although I'm failing to find out which one as I have just addblock plus 2.9.1 (and it is supposed to be compatible) and 1password.

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Did you notice an improvement when you upgraded from ADB2.9 to ADB2.9.1 as that was changed specifically to add a workround that prevented severe slowness seen by some Firefox users.

I probably will not understand the detail of the memory reports but I will glance at them later and see if anything jumps out at me as unusual.

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No, actually not. My FF has always been slow as hell, but lately it's just plain annoying.

I was attributing the slowness to the fact that I have several instances of the inspector tool open on one monitor and the pages open on another monitor, but lately I noticed that even when I start FF it seems to use way too much memory with nothing open.

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You have only posted the text output. It would help if you could find somewhere to post the full file. Note also that you may reimport those files and look at them again in about:memory. When you look at them there is some explanatory information shown as tooltips on mouseover of the lines.

Note this forum, and any file you post will be public so be careful that it does not contain sensitive information.

There is also a profiler. I understand the output of that even less but its topline shows fps Frames Per Second you would expect Firefox to be trying to achieve 60 FPS if for example you see it falling to 1FPS or lower you have serious stuttering and jank

Note the about memory will dif between reports so if you see rapid climbs in memory usage take repeated snapshots of memory, preferably with only one site and a couple of tabs open (Avoid Flash Player use and Facebook use) It at least then becomes clear what is swallowing all the RAM. Also note about:memory has a button as an option to reduce memory usage, does that help ?

How much RAM do you have installed, if you are using a 64bit OS using a lot of RAM may not necessarily be bad, unless you are running short and the OS is forced to use a PageFile/SwapFile

See also

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Sorry, I didn't see the option to save the measure information as a file.

I've made new snapshots and uploaded them to onedrive: no addons: https://1drv.ms/u/s!ArR5BL6RniuIh4ZlCvXy9KM8VKuioQ

with addons: https://1drv.ms/u/s!ArR5BL6RniuIh4ZkO5bIzRMrlAfDKw

I'm on a Macbook PRO with 16GB of RAM. I know that FF might use a lot of RAM and that it is not necessary a bad thing, but I always notice that whenever I reach around 2GB the performance drops (FF starts to hangs for few seconds & that's when I kill the process and start again)