Strange, I don't see any particular increase in traffic in our stats. However, I have now fixed our server-monitor which was hasn't been working for months, so if it happens again I may be able to find some clue.
One thing that may help in future if it happens to you is the following:
- Using Google Chrome, open a page that is loading slowly (e.g. here)
- Press Ctrl+Shift+I and a window will open at the bottom.
- Click the "Network tab".
- Reload the web page and it will record the things that get loaded.
- Take a screenshot so I can see.