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My Ubuntu is using an insane amount of ram memory. When I boot the machine it is using around 1,5 to 2 gig ram without me launching any applications. When I start firefox and vlc it maxes out. Going to 6083716 used (almost max)

I can't find the source of this memory usage. But the vlc video sound is getting distorted because of it. Also when I shutdown everything running it still stays using over 5 gig of ram.

The graphical system monitor is saying only 18 % is used but top and free say its almost all in use.

top: Mem: 6127092k total, 6083484k used, 43608k free, 22820k buffers
Swap: 6288380k total, 0k used, 6288380k free, 4948116k cached
Any ideas?

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The memory is there to be used. If the memory is not used by applications, it will be used by the system for caching, such as disc reads and writes. Unused memory is wasted memory.

As long as the swap is unused, your memory is under no stress at all.

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Seems like it is. It is scrambling my sound in vlc. – Jarco May 9 '11 at 16:31
@Jarco - what evidence is there that this is what is scrambling your sound? Not being argumentative, just thinking it sounds like a huge assumption. What might be useful is to post the output from top so we can see what is running. – Rory Alsop May 9 '11 at 17:07
I tried to paste it here. Note: I freed memory by starting and stopping a virtual machine in virtualbox. But you seem to br right. It is perhaps another problem with vlc. – Jarco May 9 '11 at 17:25

If you use the free command you'll see the -/+ buffers/cache row. That line would give you more precise of how much memory are your applications using.

My computer for example (4gb): free -m

              total       used       free     shared    buffers     cached
Mem:          3760       3155        605          0         86       1654
-/+ buffers/cache:       1414       2346
Swap:         1905         39       1866

it shows a total of 3.1gb used, but actually 2.3gb are free for my applications to use. The rest is for buffers and cache as the name implies.

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