I recently installed Ubuntu Server 12.04 on a computer with the following specs:
Pentium 4 1.5GB RAM 80GB HD
Installation went smoothly and at first it worked well. However, after doing package updates and installing OpenSSH server so I can login and restarting, the terminal is very slow. Sometimes the password prompt takes time to appear, other times after typing the password and pressing enter several minutes can pass before the login completes.
After login, commands are slow, taking minutes to execute. For example, vim takes several minutes to open a file.
The issue doesn't seem to be a memory limit. Running free -m I can see most memory is free. Running top shows no process taking any significant time (almost all are at 0%).
I added the fix for the DNS lookup fix, but the command line itself can't be taking this long because of DNS.