How to troubleshoot a problem

This is something that's harder the more familiar with the technology you become - Oh look www.stuff.com is unreachable, I'll restart apache (or whatever).

Don't get me wrong, if you can fix something fast go for it (assuming no Change Control issues), but if you're looking to actually find out what the problem is that's a different game all together.

1. Identify the actual problem. SVN checkouts are slow
2. Specify expected results (SVN should check out in X seconds)
3. Identify all of the involved systems* (network, SVN server, client, storage, which repo etc)
4. Break down the entire thing to a testable granularity (ping time to server, speed copying repo with cp locally, the same but over NFS instead of SVN, storage utilization).

Now you have the basic tools to find out what's causing your issue, not just how to resolve it.