I've noticed that Flash applications tend to be more sluggish under Ubuntu than they do under Windows on the same machine. This is particularly noticeable when watching HD video or playing graphics/physics-heavy games. Are there any ways of improving the performance of Flash under Ubuntu, or is this just an issue with the Linux version that I will have to live with?

Currently I'm just cutting down on the number of tabs open, blocking flash ads, and closing other programs, but I'm looking for ways to affect Flash itself.

Other things I have already been doing include using Youtube's HTML5 feature and playing videos straight from /tmp in VLC. I was wondering if there was some way of streamlining Flash itself though. Perhaps not.

More Specific Question: Is there anything I can do in mms.cfg to boost performance?


12 Answers 12


This is an issue with the Flash Player - the Linux version has some performance issues with playing video.

Your best bet for sites like YouTube that support HTML5 video is to use that instead. (See here for details.) The performance is much better.

  • 4
    Yeah I've been very pleased with the performance of HTML5 Youtube video. However, on sites that only offer flash video I sometimes just play it in VLC straight from /tmp
    – DLH
    Aug 4, 2010 at 22:53
  • 2
    isn't it about time adobe started to play ball with the open source people? Nov 17, 2010 at 2:51

Hardware acceleration in flash for video and graphics is currently only supported on Windows platform. See: http://www.adobe.com/devnet/flashplayer/articles/fplayer10.1_hardware_acceleration.html

  • This is not true. Guessing from the link name, I guess it's because the answer is very old, probably that was the case for the time.
    – Hi-Angel
    Jul 2, 2016 at 18:24

Alternatively you can use Gnash or Lightspark.

  • 1
    Hmm Lightspark looks interesting. Have you had any experience with it?
    – DLH
    Aug 5, 2010 at 12:52
  • Lightspark is still really memory/cpu intensive. Give it 3 months.
    – Broam
    Aug 12, 2010 at 17:30
  • linux.com/learn/tutorials/… great tutorial on how to replace flash with the two little gems @akshatj mentioned. Mar 15, 2012 at 11:54
  • @Broam Well, a few months have passed - how is it now?
    – Eyal
    Mar 19, 2013 at 21:31

I would hope your using Ubuntu. Its pretty straight forward if you use the installer given to you from the adobe website.

It might just be a low on processing power since flash is processor extensive process, also more ram might help.

Also going to System > Administration > Hardware Profiles and making sure your graphics drivers have the correct settings helps.



Try disabling desktop effects.


In addition to the suggestions above - try disabling compiz, using chrome, making sure the fastest graphics drivers are installed - you could try to override the Flash plugin's detection for hardware acceleration. I can't vouch for the usefulness of this hack, though.

  • I actually tried overriding Flash's hardware acceleration detection yesterday, and have to say that it did accomplish about a 15% reduction in CPU usage. Aug 21, 2010 at 20:21

Try using Google Chrome browser. I found it to be faster than Firefox in Ubuntu, for normal pages or those with Flash.

  • Firefox is around the same speed, and sometimes much faster than Chrome, now. When it crashes, Flash crashes the whole tab in Chromium, rather than just not showing the plugin, as Firefox does.
    – NoBugs
    Jul 17, 2013 at 4:25

If for instance you want to play a youtube video there is a workaround!

Flash buffers the video to you disk, that file will be in /tmp/ and called something like FlashXXp0sHC0, that is Flash + 8 random chars. You can play it in a normal player, or even copy it somewhere else for offline viewing (Note that in most countries it is illegal to copy the file since it a breaches copyright).

This approach will work on a lot of sites but depends on what the streaming format is. If in doubt you can use the file utility to detect what is in the file

user@host:~$ file /tmp/FlashXXp0sHC0
/tmp/FlashXXp0sHC0: ISO Media, MPEG v4 system, version 2

user@host:~$ file /tmp/FlashXXLE3wCf
/tmp/FlashXXLE3wCf: Macromedia Flash Video
  • 1
    Yes, I mentioned this workaround in my question.
    – DLH
    Aug 14, 2010 at 5:06
  • I should apparently be more careful when reading a question. Aug 14, 2010 at 13:49
  • 2
    Copying a file around on your filesystem has nothing to do with copyright. Distributing that file (providing other people access to that file) is when copyright (and license, if any) matters.
    – Roger Pate
    Aug 15, 2010 at 18:47
  • 1
    As soon as you close the flash application that saved the file in the first any copies of that file that remains on the computer is an illegal copy, at least here in Denmark. But everyone should find out how the their local legislation works. Aug 15, 2010 at 20:41

I am running Ubuntu 12.04 64-bit with an Nvidia GeForce 8400 GS. I have had Flash-related issues since performing a clean install of 12.04. Just like you, I have installed the proprietary drivers, but System Settings > Details lists Graphics as "Unknown."

I was having speed issues, but most annoylingly, the same issues as reported in Flash video appears blue on this forum. Following the workaround posted at the previous link stopped the unwanted behavior of all Flash video being tinted blue, but ended up causing the Flash plugin to crash nearly every time I attempted to watch a video online.

The solution for me was to look back at /etc/adobe/mms.cfg and remove everything but one line, which should read:


If you are not sure how to do this, you can use your favorite text editor (for me it's vi) or you could pop open gedit with the following terminal command:

sudo gedit /etc/adobe/mms.cfg

Write in the OverrideGPUValidation=true line from above, save the file, and quit gedit. Restart your browser and see if this solves the problems you are having.

This idea and others are discussed on ubuntuforums, and many other places. Please try changing your mms.cfg (or creating it, if it does not already exist) and post back with your results. Good luck!


If you're using the AMD64 build of Ubuntu, try downloading the beta AMD64 flash player. The x86 build is run through an emulation layer that I've had tons of problems with.

  • The AMD64 build has security holes and is unsupported.
    – Broam
    Aug 12, 2010 at 17:31

I experienced the same annoyance under Ubuntu 12.04.3 on my netbook [Asus 1005PE, Intel GMA3150 video chipset, linux-generic-lts-raring kernel + xserver-xorg-video-intel-lts-raring]

In addition to the /etc/adobe/mms.cfg file workaround, I went to compizconfig settings manager (if not installed, sudo apt-get install compizconfig-settings-manager) and completely disabled the "dim windows" option under Effects, at the bottom section.

Less load on the system (without even giving up on Unity nor adobe-flashplugin), and voilà, fullscreen flash videos don't stutter now.


Flash video files are no longer in /tmp
this is a script that will locate and play the streaming flash video file using the Player
of your choice
If the stream is not fast enough there is no buffering the player will just stop or exit

To use it pause the streaming media and run the script
I use this command on a launcher with it
video smplayer "-close-at-end -fullscreen -minigui"
I saved the script to /usr/local/bin/video
If you use echo for the player parameter it will print the path to the video

This will not work on streams use DRM

Technically the answer to the question is cause flash is a piece of junk that should have died off a few years ago.

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