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The computer is an EliteBook 8540w:

  • ATI FirePro 5800 (using proprietary drivers)
  • i7 720qm
  • 8Gb RAM
  • OCZ Agility III SSD

Ubuntu is freshly installed (a week ago). I have set swapiness to 10. When I'm on AC, I have the governor (using Jupiter) set on performance. top shows no process over 10% and total never over 20%. Half of the RAM is unused and swap is empty.

And yet again, when I open a few browsers (Firefox with Flash disabled), Thunderbird, Skype, Smuxi, IDE (eclipse or JDev) and maybe some other program I need for work, the system starts being sluggish (desktop switching slow, overview slow (if I press win key), scrolling in programs slow).

Is there any other thing I should tweak to make this thing run smoothly?

Used iotop, to find out what's hogging my IO (if anything): Firefox was caching and hogging the resources, I've increased the amount of memory it can use, still not nice but better, heard a leak was fixed in 15, but it's not in the updater yet (will wait). Also noticed that Smuxi (IRC client) was not playing nice, removed, switched to empathy (default). Added noatime to / disk mount, will post results after reboot.

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If neither CPU nor memory is the bottleneck its probably I/O or graphics, check I/O with iostat -xk 1 (check %util column), for the graphic card I can't really tell, maybe run glxgears?

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There's also a terminal tool called iotop (same functionality/usability as htop) to accomplish this. Perhaps that's more to your liking. – FuzzyQ Aug 4 '12 at 18:34
up vote 1 down vote accepted

The problem was graphics. Don't know why, but the open drivers which I didn't uninstall prior to installing (manually) the new ones messed up things.

fglrxinfo showed the correct info, so I thought it was okay, but fgl_glxgears were going only up to 60 FPS (with tearfree and vsync off).

So I cd-ed to the location where I had fglrx driver already in the .deb format and I:

sudo service lightdm stop
sudo apt-get remove xserver-xorg-video-radeon
sudo apt-get remove --purge fglrx*
sudo dpkg -i fglrx*.deb
sudo service lightdm start

fglrxinfo still correct, fgl_glxgears @ 800-1000 FPS ...

Much better.

10x for the pointers

UPDATE: another thing I've noticed ... sometimes (usually after resume from sleep) jupiter switches to performance governor but the CPU frequencies are stuck at lowest (as id it was using powersave governor). Use Jupiter of whatever you use to switch governors and change the governor to ondemand (and then back to performance if you wish). CPUs will then go over the minimal frequency.

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Just install a realtime (package name "linux-lowlatency") kernel and gnome will be smooth. Use synaptic packet manager to find it, also you can uninstall the generic kernel to round things up.

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