I've just migrated to a new dedicated server and am experiencing a very strange issue.
All the PHP sites are taking too long for the first load ( some even up to 15 seconds, whereas on the old server they would load in 2-3 seconds ). After the initial load, they load very fast ( faster than on the old server ). Hardware wise, this new server is better so that's not the issue. I'm guessing it's something related to the way PHP is configured.