Ask Ubuntu is a question and answer site for Ubuntu users and developers. It's 100% free.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I have Ubuntu installed on my laptop with the following disk organization:

  • 20 GB for /
  • 5 GB for /home

The large root I have was intended in principle for installing large pieces of scientific software, but in fact I don't have any of that software installed currently. I have checked my disk space for installing ubuntu 12.04 and I have found that it takes ~15 GB. I have checked on the web that a typical installation should be ~4-6 GB.

How can it be? I don't have big pieces of software, I have also removed the Office Suite to have more space. I keep all my data somewhere else. My installation is pretty minimal. I have already removed all the old kernel and header files, cleaned with apt-get autoremove and removed any unused piece of software with Computer Janitor.

In fact I found 4.5GB of scientific software I had forgotten about, nonetheless the installation would be 10.5 GB without those pieces of software, that seems still a lot to me. I also have the full tetex-latex installed.

The upgrade to 12.04 require 5GB of space, and I had to remove 3.5GB of that optional software I had.

Now I have the following:

Filesystem                Size  Used Avail Use% Mounted on
/dev/sda8                  20G   15G  4.3G  78% /
udev                      993M  4.0K  993M   1% /dev
tmpfs                     401M  860K  400M   1% /run
none                      5.0M     0  5.0M   0% /run/lock
none                     1003M  7.0M  996M   1% /run/shm
/dev/sda6                 5.0G  4.1G  612M  88% /home

that 15GB still look like a lot, it is 3.5GB more than v10.04

output of sudo du -hs --exclude=/proc /*

8.6M    /bin
32M     /boot
0       /cdrom
460K    /core
4.0K    /dev
20M     /etc
0       /
0       /initrd.img
176M    /lib
4.4M    /lib64
16K     /lost+found
32K     /media
458M    /opt
116K    /path
19M     /root
1.1M    /run
9.3M    /sbin
4.4G    /scratch
4.0K    /selinux
200K    /srv
0       /sys
104K    /tmp
6.6G    /usr
520M    /var
0       /vmlinuz
share|improve this question
Can you add the output of df -h to your question just to provide some evidence. Check also how many kernels/headers you have installed - there are usually way too many, and removing all but last should free a lot of space. The command to do that is dpkg -l | grep "ii linux" – mikewhatever Aug 25 '13 at 21:44
all the unused kernels had been previously removed – simona Aug 25 '13 at 23:36
So, apparently something takes up space. Can you add the output of sudo du -hs --exclude=/proc /* as well. ...almost forgot, have you tried sudo apt-get clean? That deletes all the cached installation packages. – mikewhatever Aug 26 '13 at 0:13
The output above shows that the most space is taken by 4.4G /scratch, and 6.6G /usr. Everything else is pretty insignificant. – mikewhatever Aug 26 '13 at 20:01
without the software that I have installed in /opt and \scratch, the total installation is 7.4GB. is it typical? – simona Aug 26 '13 at 20:10

This is because the installer needs to download the updates packages first, which pretty much sums 3 times what you are using right now. Example:

You have 3 GB of programs installed, the packages to upgrade all that weights about 1.7 GB, now all those packages need to be uncompressed when installing, so you will be using 3 GB or more extra. The grand total 7.7 GB of data to do a full upgrade. That's why you need the extra space when upgrading from a release to another. In your case, since you have already /home in another partition, just install Ubuntu 12.04 on top of the root filesystem. Tell the installer that you want to use the old /home without formating, and you should be in 12.04 pretty quick.

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.