Dramatic increase in RAM usage when viewing several videos in a row

[Serhiy]

I guess the reason is that Firefox doesn't delete huge cached video files from already closed pages/history and Linux is still keeping them in cached-disk RAM which leads to quick plummeting into swap and overwhelmingly reduced performance.

Steps to reproduce:
View several [long] videos on Vimeo/Youtube in a row.
System starts going into swap after several videos which is really uncomfortable on a 5400-rpm HDD.
Restart Firefox.
The video that was playing before the restart will easily be played and everything is okay unless you decide to watch more videos in a row.

vm.swappiness = 25

ProblemType: Bug
DistroRelease: Ubuntu 15.04
Package: firefox 40.0+build4-0ubuntu0.15.04.4
ProcVersionSignature: Ubuntu 3.19.0-26.28-generic 3.19.8-ckt4
Uname: Linux 3.19.0-26-generic x86_64
AddonCompatCheckDisabled: False
ApportVersion: 2.17.2-0ubuntu1.3
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC0: int 1583 F.... pulseaudio
BuildID: 20150819100530
Channel: Unavailable
CurrentDesktop: KDE
Date: Thu Aug 27 04:20:26 2015
Extensions: extensions.sqlite corrupt or missing
ForcedLayersAccel: False
IfupdownConfig:
 # interfaces(5) file used by ifup(8) and ifdown(8)
 auto lo
 iface lo inet loopback
 #auto eth0
 #iface eth0 inet dhcp
IncompatibleExtensions: Unavailable (corrupt or non-existant compatibility.ini or extensions.sqlite)
IpRoute:
 default via 192.168.0.1 dev ra0 proto static metric 1024
 169.254.0.0/16 dev ra0 scope link metric 1000
 192.168.0.0/24 dev ra0 proto kernel scope link src 192.168.0.3
Locales: extensions.sqlite corrupt or missing
Plugins:
 IcedTea-Web Plugin (using IcedTea-Web 1.5.2 (1.5.2-1ubuntu2)) - /usr/lib/jvm/java-7-openjdk-amd64/jre/lib/amd64/IcedTeaPlugin.so (icedtea-7-plugin)
 Google Talk Plugin Video Renderer - /opt/google/talkplugin/libnpo1d.so (google-talkplugin)
 Google Talk Plugin - /opt/google/talkplugin/libnpgoogletalk.so (google-talkplugin)
 Shockwave Flash - /usr/lib/adobe-flashplugin/libflashplayer.so (adobe-flashplugin)
PrefSources:
 prefs.js
 [Profile]/<email address hidden>/defaults/preferences/prefs.js
Profiles: Profile0 (Default) - LastVersion=40.0/20150819100530 (In use)
RelatedPackageVersions:
 icedtea-7-plugin 1.5.2-1ubuntu2
 google-talkplugin 5.41.0.0-1
 adobe-flashplugin 1:20150811.1-0vivid1
RunningIncompatibleAddons: False
SourcePackage: firefox
Themes: extensions.sqlite corrupt or missing
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 06/09/2013
dmi.bios.vendor: American Megatrends Inc.
dmi.bios.version: X502CA.209
dmi.board.asset.tag: ATN12345678901234567
dmi.board.name: X502CA
dmi.board.vendor: ASUSTeK COMPUTER INC.
dmi.board.version: 1.0
dmi.chassis.asset.tag: No Asset Tag
dmi.chassis.type: 10
dmi.chassis.vendor: ASUSTeK COMPUTER INC.
dmi.chassis.version: 1.0
dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvrX502CA.209:bd06/09/2013:svnASUSTeKCOMPUTERINC.:pnX502CA:pvr1.0:rvnASUSTeKCOMPUTERINC.:rnX502CA:rvr1.0:cvnASUSTeKCOMPUTERINC.:ct10:cvr1.0:
dmi.product.name: X502CA
dmi.product.version: 1.0
dmi.sys.vendor: ASUSTeK COMPUTER INC.

[Paul White (paulw2u)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. We are sorry that we do not always have the capacity to look at all reported bugs in a timely manner. There have been many changes in Ubuntu since that time you reported the bug and your problem may have been fixed with some of the updates. It would help us a lot if you could test it on a currently supported Ubuntu version.

When you test it and it is still an issue, kindly upload the updated logs by running only once:

apport-collect 1489220

and any other logs that are relevant for this particular issue.

[Launchpad Janitor (janitor)]

[Expired for firefox (Ubuntu) because there has been no activity for 60 days.]