ASL stands for Apple System Logger. If your Mac is launching Terminal very slowly, try clearing your ASL logs.

$ sudo rm -f /private/var/log/asl/*.asl

Check out http://www.proposedsolution.com/solutions/osx-terminal-slow-launch for preventative measures.

All I did was add the following lines to /etc/asl.conf.

= archive 0
= utmp_ttl 604800
= fs_ttl 604800

“So, you want to know what’s happening right?

• The first parameter = archive 0 disables archiving.  I like to set this because I have no desire to retain masses of archived versions of my logs.  That’s a zero after the word archive by the way.
• utmp_ttl sets the time-to-live for messages in seconds.  604800 is 7 days.  Set this to the length of time you would like.
• fs_ttl is the time-to-live for filesystem errors.  This is in seconds too.”