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jmz2
September 25th, 2010, 11:05 AM
Hello,

It is normal that I have a used RAM of 150mb just after installacion of a minimun server install? Is an Ubuntu server 10.4 64bit with nothing running but SSH

It surprise me because I had installed in the same hardware the Lubuntu 10.4 32bit which has full desktop an it used only 70Mb after installation.

Why so much RAM consumption?

Thanks.

jmz2
September 26th, 2010, 11:43 AM
How much RAM is your Ubuntu Server 10.4 in idle and nothing running?

CharlesA
September 26th, 2010, 03:18 PM
How are you measuing the RAM used?

Try this:


free -m

jmz2
September 26th, 2010, 04:15 PM
I use 'htop' normally to measure RAM use.

This is what I get using 'free' after just reboot:



jrg@hp-ml150:~$ free -m
total used free shared buffers cached
Mem: 5854 222 5632 0 27 44
-/+ buffers/cache: 150 5703
Swap: 0 0 0

Normally, how much RAM does Ubuntu Server 10.4 64bit uses when installed with the minimum?

Thnaks.

CharlesA
September 26th, 2010, 10:35 PM
That looks fine.

You've got 6 gigs or RAM, why do you care if the main OS uses 150MB or 75MB of it?

Here's what mine looks like, but keep in mind this is just a virtual machine (I did a full install of Ubuntu Server 10.04.1)


charles@luna:~$ free -m
total used free shared buffers cached
Mem: 999 84 915 0 12 24
-/+ buffers/cache: 47 952
Swap: 1101 0 1101

This is what my main server looks like:


charles@thor:~$ free -m
total used free shared buffers cached
Mem: 5981 5306 675 0 4 1485
-/+ buffers/cache: 3816 2165
Swap: 12401 0 12401

Then again, that machine is running 5 VMs atm.

jmz2
September 26th, 2010, 10:56 PM
That looks fine.

You've got 6 gigs or RAM, why do you care if the main OS uses 150MB or 75MB of it?

I don't really care but surprise me that the figure is so high and thought that maybe is something to do with my hardware.


charles@luna:~$ free -m
total used free shared buffers cached
Mem: 999 84 915 0 12 24
-/+ buffers/cache: 47 952
Swap: 1101 0 1101[/code]

Is that a Version of 32 or 64bits?

This is one virtual machine with Ubuntu Server 10.4.1 32bits, this is why the 150Mb surprise me:


ge@ubuntu-nas:~$ free -m
total used free shared buffers cached
Mem: 189 79 110 0 15 39
-/+ buffers/cache: 23 165
Swap: 149 0 149

CharlesA
September 26th, 2010, 11:05 PM
They are both 64-bit.

Here's with all the VMs powered off:


charles@thor:~$ free -m
total used free shared buffers cached
Mem: 5981 3681 2300 0 3 3316
-/+ buffers/cache: 361 5619
Swap: 12401 0 12401

It is running: SSH, Samba, Apache, Exim4, and a few other services.

R.Bucky
September 27th, 2010, 12:51 AM
My Server edition install uses around 1500MG RAM after a few hours. Upon initial startup, RAM usage sits around 300MB. However, once Apache gets going and people view a couple of my sites, RAM usage climbs. I have noticed that the 64-bit version really uses whatever RAM is available to make services and content more readily available, where the 32-bit version did not. Difference in architecture makes a difference...

windependence
September 27th, 2010, 12:59 AM
Linux != Windows.

Linux uses available RAM if it can. In some cases all available RAM will appear to used and in fact it IS used, but just not the way it is used in Windoze. This is a good thing. Linux will cache programs in RAM until they are ready to be used thus increasing performance and why not? If you've got the resources why not use them?

-Tim

CharlesA
September 27th, 2010, 01:21 AM
My Server edition install uses around 1500MG RAM after a few hours. Upon initial startup, RAM usage sits around 300MB. However, once Apache gets going and people view a couple of my sites, RAM usage climbs. I have noticed that the 64-bit version really uses whatever RAM is available to make services and content more readily available, where the 32-bit version did not. Difference in architecture makes a difference...

Yep, that's the way Linux manages memory.


Linux != Windows.

Linux uses available RAM if it can. In some cases all available RAM will appear to used and in fact it IS used, but just not the way it is used in Windoze. This is a good thing. Linux will cache programs in RAM until they are ready to be used thus increasing performance and why not? If you've got the resources why not use them?

-Tim

+1.

Check here (http://www.linuxatemyram.com/) as well. ;)