It doesn't necessarily need to be the host (a sleep 18 in your code would give similar timing), but it does sound like a system issue.

Have you checked how busy that machine is? Check some of these commands:

uptime
free
ulimit
df -H
ps aux
[download]

You get the idea.

If those aren't the issue, is connecting to the database a problem? Opening sockets? What else does your code do that interacts with the OS?