4 Replies Latest reply on Nov 24, 2010 8:07 AM by UlyssesOfEpirus

    Adobe flash makes VM unresponsive

    UlyssesOfEpirus Hot Shot

      In a linux VM, command "nice" allows the user to launch a process with a priority that is higher or lower than normal, so it uses more or less percent of cpu power.  The user can also lower or raise the priority of a running process with tools like "htop".

       

      But is it possible for the user to lower the priority of a specific thread within a running process?

       

      The reason I'm asking, the adobe flash plugin for firefox makes the entire user interface of a linux VM unresponsive when the cpu runs at 100%.  Seen the same happen when the priority of a cpu-intensive process is raised too much.  So it is logical that flash runs some threads in too

      high priority, and we don't want that.

       

      Any tricks to slow down a firefox plugin (.so executable) like flash?

        • 1. Re: Adobe flash makes VM unresponsive
          birdie Master

          Firefox 3.6.x creates a separate process for running flash plugin - you can alter its priority automatically by e.g. running this script (save it to a file, and make it executable using 'chmod +x filename.sh' command):

           

          #! /bin/bash
          
          while :; do
                renice 20 -p `ps ax | grep plugin-container | grep -v grep | awk '{print $1}'` &> /dev/null
                sleep 1
          done

           

          However this script won't address the core problem with your flash - the fact that it uses 100% of CPU time.

           

          I'd suggest going to youtube, right clicking any video, choosing "Settings ..." and disabling/enabling "Hardware acceleration".

          • 2. Re: Adobe flash makes VM unresponsive
            UlyssesOfEpirus Hot Shot

            That's cool.  Will require some testing. 

             

            There seem to be several processes associated with the flash plugin, seen this in htop, can also be seen if you type:

             

            top -H -n 1 | grep plugin-cont

             

            Can't find how the same can be done with "ps".  Do you know?

            • 3. Re: Adobe flash makes VM unresponsive
              birdie Master

              Hm, probably you're right, we need to change all threads priority:

               

              renice 20 -p `top -H -n 1 | grep plugin-cont | grep -v grep | awk '{print $2}'` &> /dev/null

               

              • 4. Re: Adobe flash makes VM unresponsive
                UlyssesOfEpirus Hot Shot

                Command "top" doesn't show them all, in htop if you press F5 it shows 4 of them when watching a youtube video.   Whereas "top" shows 2 or 3.

                 

                So "ps" must be the right way to do it, as alluded in my previous post.  But what parameters do you  give to "ps" to make it show a tree view that includes all threads?