Sunday, April 29, 2012

Ubuntu distros: RAM & CPU usage of Ubuntu, Xubuntu, Kubuntu & Lubuntu

An interesting suggestion came for comparing the RAM & CPU usage of the four Linux sisters: Ubuntu 12.04 LTS, Kubuntu 12.04 LTS, Xubuntu 12.04 LTS & Lubuntu 12.04 LTS.

As mentioned in my previous post, Ubuntu seemed to be the most taxing on CPU & RAM whereas Lubuntu seemed to be the least. The same results are validated when I booted each of them from pen drive and checked the RAM & CPU usage.

Distro Xubuntu 12.04 LTS Ubuntu 12.04 LTS Kubuntu 12.04 LTS Lubuntu 12.04 LTS
CPU Usage 6%-10% 17%-18% 3%-10% 1%-11%
RAM Usage 130 MiB 340 MiB 235 MiB 126 MiB

In nutshell, Lubuntu uses least RAM and CPU. Xubuntu is very close to Lubuntu. Kubuntu lies somewhere in the middle with about 235 MiB RAM usage and Ubuntu, of course, with the effects of Unity (2D here) and other graphics, uses about 50% more RAM than Kubuntu.

Limitations: All these are without any programs running and booted from pen drive. After installation and updating, the actual RAM & CPU usage may be slightly higher.


One additional comment: Please check my review on Linux Mint 13 LTS with Gnome 2 before deciding on what distro you would like to install.


  1. thanks for the info, now I'm totally sure to download the xfce enviroment, no matter if only have 3year support lts.

  2. Well I'm a newbie with 2 months trying linux (debian squeeze+xfce(4.6),ubuntu 12.04 with gnome-panel) ....and I'm still don't know what to believe:

    ubuntu 12.04 x86_amd64 with gnome fallback
    with task manager: 334MB used
    with command free: 654MB used

    xubuntu 12:04 x86_amd64 (xfce 4.8)
    task manager: 180MB used
    with command free: 450MB used

    Mint 13 maya x86 (avoiding some services at startup)
    task manager: 152MB used
    with command free: 477Mb used

    Debian squeeze x86 (xfce 4.6)
    task manager: 74MB
    with command free: 114MB used

    Please somebody give some lights....any tool to measure the average ram usage?

    1. Hi Luis, I checked Debian squeeze 6.0.5 and currently I am running it on my system. Lower RAM and CPU usage is primarily due to Gnome 2.30.* desktop. Gnome 3 in Ubuntu 12.04 is much more RAM intensive. By the by, I really liked Debian squeeze :). Thank you for sharing your findings.

  3. Luis, I guess system monitor gives you the average RAM & CPU usage in ubuntu. Based on you what you've provided, debian squeeze seems pretty impressive. I haven't tried it yet but want to try it for sure. Is it bootable from usb? Also, my experience tells me xfce, lxde & enlightenment uses lower resources comparatively than gnome or kde. Hope it helps.

  4. Lubuntu 12.04 LTS 32b is using 90MB when booted (P3 with 512MB).
    Compared with 126MB when using the live media.

    Still very responsive !

    Xfce is not the problem, Xubuntu is: when comparing Debian 7 XFCE and Xubuntu, I wonder where is the memory gone

    1. Debian is way way lighter than Ubuntu, any day. But, Ubuntu is more user friendly and good for Linux novices.