Firefox freezing system by occupying all RAM

[Hadmut Danisch]

For several days, some weeks maybe, I'm suffering from the problem that every now and then (several times a day) firefox runs into a state where it occupies all available RAM.

Sometimes it is still possible with patience, because mouse and keyboard become slow and other programs can't run, to kill firefox or start QPS with CTRL-ALT-DEL.

In almost all cases QPS shows that there are four of the many firefox processes having occupied more than 4GB RAM each. Since my PC has 16GB RAM, all is occupied.

In most cases it is not possible to kill firefox anymore (because I can't get even an existing shell window to become active or start QPS) and not even properly shut down the PC with a short press on the power button.

It is never a single firefox task running berserk, it's always four or more. Maybe some memory leak.

Maybe this is not caused by a new bug, but possibly by new ADS on web pages.

Unfortunately, it doesn't seem to be possible to limit the memory space to be occupied by firefox, since limits apply to single processes, and firefox opens a process per browser window or tab.

However, we should have some method to limit the mem space firefox can occupy.

ProblemType: Bug
DistroRelease: Ubuntu 20.04
Package: firefox 90.0.2+build1-0ubuntu0.20.04.1
ProcVersionSignature: Ubuntu 5.4.0-80.90-generic 5.4.124
Uname: Linux 5.4.0-80-generic x86_64
NonfreeKernelModules: zfs zunicode zavl icp zcommon znvpair
AddonCompatCheckDisabled: False
ApportVersion: 2.20.11-0ubuntu27.18
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC0: hadmut 6445 F.... pulseaudio
BuildID: 20210721174149
CasperMD5CheckResult: skip
Channel: Unavailable
CurrentDesktop: LXQt
Date: Mon Aug 9 19:39:26 2021
DefaultProfileExtensions: extensions.sqlite corrupt or missing
DefaultProfileIncompatibleExtensions: Unavailable (corrupt or non-existant compatibility.ini or extensions.sqlite)
DefaultProfileLocales: extensions.sqlite corrupt or missing
DefaultProfilePrefErrors: Unexpected character ',' before close parenthesis @ /usr/lib/firefox/omni.ja:greprefs.js:352
DefaultProfilePrefSources: prefs.js
DefaultProfileThemes: extensions.sqlite corrupt or missing
ForcedLayersAccel: False
InstallationDate: Installed on 2020-06-12 (422 days ago)
InstallationMedia: Lubuntu 20.04 LTS "Focal Fossa" - Release amd64 (20200423)
Profile0Extensions: extensions.sqlite corrupt or missing
Profile0IncompatibleExtensions: Unavailable (corrupt or non-existant compatibility.ini or extensions.sqlite)
Profile0Locales: extensions.sqlite corrupt or missing
Profile0PrefErrors: Unexpected character ',' before close parenthesis @ /usr/lib/firefox/omni.ja:greprefs.js:352
Profile0Themes: extensions.sqlite corrupt or missing
Profile1Extensions: extensions.sqlite corrupt or missing
Profile1IncompatibleExtensions: Unavailable (corrupt or non-existant compatibility.ini or extensions.sqlite)
Profile1Locales: extensions.sqlite corrupt or missing
Profile1PrefErrors: Unexpected character ',' before close parenthesis @ /usr/lib/firefox/omni.ja:greprefs.js:352
Profile1Themes: extensions.sqlite corrupt or missing
Profile3Extensions: extensions.sqlite corrupt or missing
Profile3IncompatibleExtensions: Unavailable (corrupt or non-existant compatibility.ini or extensions.sqlite)
Profile3Locales: extensions.sqlite corrupt or missing
Profile3PrefErrors: Unexpected character ',' before close parenthesis @ /usr/lib/firefox/omni.ja:greprefs.js:352
Profile3PrefSources: prefs.js
Profile3Themes: extensions.sqlite corrupt or missing
Profiles:
 Profile3 - LastVersion=78.0.1/20200630195452 (Out of date)
 Profile2 (Default) - LastVersion=90.0.2/20210721174149 (In use)
 Profile1 - LastVersion=None/None (Out of date)
 Profile0 - LastVersion=None/None (Out of date)
RunningIncompatibleAddons: False
SourcePackage: firefox
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 10/12/2012
dmi.bios.vendor: American Megatrends Inc.
dmi.bios.version: H61TIW08.111
dmi.board.asset.tag: To be filled by O.E.M.
dmi.board.name: H61H2-TI2
dmi.board.vendor: Medion
dmi.board.version: 1.0
dmi.chassis.asset.tag: To Be Filled By O.E.M.
dmi.chassis.type: 3
dmi.chassis.vendor: Medion
dmi.chassis.version: 1.0
dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvrH61TIW08.111:bd10/12/2012:svnMedion:pnG24:pvr1.0:rvnMedion:rnH61H2-TI2:rvr1.0:cvnMedion:ct3:cvr1.0:
dmi.product.family: To be filled by O.E.M.
dmi.product.name: G24
dmi.product.sku: To be filled by O.E.M.
dmi.product.version: 1.0
dmi.sys.vendor: Medion