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umpirsky
Asked: 2011-05-23 08:59:49 +0800 CST

Where has all the RAM gone?

  • 772

I have 1GB of RAM, and when I run NetBeans and Firefox, they get about 300MB of RAM. At some point, the system becomes very slow, probably 100 times slower than normal, switching windows (Alt+Tab) becomes a huge task and the computer is practically useless. This is probably the moment when it starts to swap.

Two questions:

  1. According to images provided, where has all the RAM gone? When I calculate all the processes memory, it is far smaller then 1GB.
  2. Is it normal for system to become 100 times slower when the RAM is full and using swap space?

On another computer with 4GB of RAM I have no problems.

enter image description here enter image description here

Update: I added 2GB of RAM, now I have 3GB. Anyone who wants to use heavy apps with 1GB on Unity, I don't think it's going to work. Works fine on an empty desktop :)

11.04

4 Answers

  1. Best Answer

    1. Under View make sure you have selected All Processes :

      enter image description here

    2. Yes, that's normal. Swap space on a hard drive is muuuuuch slower than RAM.

    • 13

  2. Yes, it's normal for your system to be extremely slow, or entirely unusable when your RAM is full (Trust me, I only have 2GB of RAM).

    • 3

  3. I suggest you take a look at this article https://help.ubuntu.com/community/SwapFaq you can tune your swap usage here (make it use swap later/earlier)

    • 3

  4. Did you encrypt your home folder by any chance? I did and it also created an encrypted swap (it only does so on when installing ubuntu).

    That swap besides slowing my boot time seems to be extremely slow: For compassion I used a Pentium 4, 1GB of RAM as my main PC (home encrypted but not swap I think) and never swapping was so bad like now that I switched to a Core I5 laptop with 4GB of RAM.

    I need to use swap when working with PDF's (most related programs seem to forget that /tmp exists..)

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