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Why isn't memory being released upon closing windows/tabs?

  • 5 replies
  • 3 have this problem
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  • Last reply by rklevy

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I've been using Firefox for years and I've become increasingly annoyed with this problem. None of the posted questions/answers fix this problem...I've gone into safe mode and verified that no addons are running...yet, FF fails to release memory once a tab/window is closed...in fact, memory usage becomes additive over time to the point that FF becomes sluggish and/or crashes. The problem seems to be worse when opening a window (such as a popup sub-window) inside an open tab. The only work around I have found is to use the "Memory Restart" addon to restart and restore tabs in FF...the problem is I'm doing this almost every 5 minutes or so. This is a problem with coding in FF, not an addon problem (given that no addons were running and I can still duplicate the problem). About:memory and using GC and CC does nothing to correct this problem. What is going on and when is this problem going to be resolved? This has been on long term ongoing issue (per many prior posts on this issue).

I've been using Firefox for years and I've become increasingly annoyed with this problem. None of the posted questions/answers fix this problem...I've gone into safe mode and verified that no addons are running...yet, FF fails to release memory once a tab/window is closed...in fact, memory usage becomes additive over time to the point that FF becomes sluggish and/or crashes. The problem seems to be worse when opening a window (such as a popup sub-window) inside an open tab. The only work around I have found is to use the "Memory Restart" addon to restart and restore tabs in FF...the problem is I'm doing this almost every 5 minutes or so. This is a problem with coding in FF, not an addon problem (given that no addons were running and I can still duplicate the problem). About:memory and using GC and CC does nothing to correct this problem. What is going on and when is this problem going to be resolved? This has been on long term ongoing issue (per many prior posts on this issue).

All Replies (5)

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Hi rklevy, I understand that memory is not being released when you close tabs in Firefox and there is a growing concern for the tools that are currently implemented to change the memory usage in about:memory that are not making a different in your situation.

Have you tried the RamBack add on that frees unused memory: Ramback

Please also see some about:config entries that you can use to minimize memory http://kb.mozillazine.org/Memory_Leak

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Unfortunately, RamBack does nothing to help this problem. I have also tried most of the suggestions on the link you provided. The only one that seems to at least slow down the issue (although does not completely get rid of it) is the addition of the new integer key, image.mem.min_discard_timeout_ms. Many of the pages I access contain heavy image content but still, upon closing the main tabs of these pages, the memory usage is very high on my system..right now it is at 391 Mb out of 2Gb. While typing this response, I had another tab open for reference purposes (with minimal graphics/images) , I just closed it, and the memory only dropped to 379 Mb. The only work around I have found is the "Memory Restart" addon which closes and reopens FF, restoring existing tabs when it is complete.

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Hi rklevy, I understand that memory is not decreasing when you close a tab and that we have tried all the recommended troubleshooting to minimize memory.

I did an experiment in about:memory. I measured with 15 tabs open, some with a high amount of data, and others not. It went down the total amount the tab was using after I measured it immediately. However it went up over time with the other heavy pages still open.

General performance. Currently for your system, this is pretty good. Looking at the system requirements for Firefox 32.0.3 at least 512 MB of RAM is required.

Addons and customized features will add to the memory Firefox uses.

However, in order to contribute to the performance testing, Firefox also has Firefox Health Reports http://mzl.la/171LPjo that

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Unfortunately, the very last portion of your reply was cut off...will you restate please?

In any case, you seem to agree that the memory usage, over time, does increase when heavy data pages are left open. This is the problem I was mentioning. This is a problem for those of us with limited ram. I have a 2Gb machine so having Firefox requiring at least 512 Mb, plus the increased usage of memory for tabs with heavy graphics/data, as well as normal software running in background, pushes the limits of the computer and causes the freezes I mentioned previously. I have this problem with only 2 or 3 tabs open and ALL addons/extensions turned off, although with extensions turned off, it does take somewhat longer to see the problem. Unfortunately, I can not add any more memory to my computer...it is at it's maximum at present.

I have had to switch to Google Chrome until this issue can be resolved.

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Other computers we are using now are experiencing this same problem ...we have been forced to move to Chrome which does NOT have these problems. I'm a long time user of Firefox and have always enjoyed using it...unfortunately, Firefox is no longer usable for us and we have no other alternative than to move to a browser which does not suffer from the current memory problems of the current version of Firefox.

Sorry but it's time to move on!