I have ubuntu 12.10 server, used mostly as fileserver + router. Some times ago it starts behave very strange, for example file transfer from samba server via 1GB/s link becomes very slow(less than 1MB/s)

After some research and play with network, i found that I have 100% of my / partition usage.

Filesystem                   Size  Used Avail Use% Mounted on

/dev/md1                     3.1G  3.1G     0 100% /

/dev/sda1                    105M  144k  104M   1% /boot/efi

/dev/md2                      52G  1.5G   48G   3% /usr

/dev/md4                      52G   13G   37G  26% /home

/dev/md5                      21G  181M   20G   1% /tmp

/dev/md3                     155G  824M  147G   1% /var

/dev/md6                      21G  437M   20G   3% /var/log

It's a problem, and I think to solve it by moving /lib (2.3G) folder to another directory, and mount it at startup. System is installed on software raid0, so, repartitioning will be very difficult, as I consider.

1. Is it like a root of network problems?


2. What problems will I face if I tried to do smth like rsync /lib folder to /home/root/lib?


3. Can I merge /lib and /home/lib contents and then mount latter to /lib?
   

P.S. I wonder, how it occured. When I'm partitioning my disk, I thought, that all programms will be instaled at /home, or at user folders, which i made big enought… Where can I read about what partitions are used for what programms?

edited:
At site I found:

"The directories /bin, /lib, and /etc should never be separate partitions! At boot time, only / is mounted initially. The init program needs to access files in /etc and the bootup scripts need access to commands in /bin, which may depend on files in /lib. Kernel modules required to complete the boot process are also kept in /lib.
"

So, i can't move /lib to another partition.
Can I clear it or smth else?

/lib/modules contains:

3.5.0-17-generic  3.5.0-26-generic  3.5.0-30-generic  3.5.0-34-generic  3.5.0-40-generic

3.5.0-23-generic  3.5.0-27-generic  3.5.0-31-generic  3.5.0-37-generic  3.5.0-41-generic

3.5.0-25-generic  3.5.0-28-generic  3.5.0-32-generic  3.5.0-39-generic  3.5.0-42-generic

Do I need all this files?