Load problems on kiwi and quince

[chris]

The load on the live server today was such that it ended up in off-line mode.

It's now right down again, after these things were done:

1. Munin has been stopped on kiwi, there are alternative stats here:
   • ​https://ecodissident.net/munin/webarch.net/kiwi.webarch.net/
   • ​https://ecodissident.net/munin/webarch.net/quince.webarch.net/
2. "DTS Agent" (which appears to be a spam bot) was requesting a huge number of pages so it's been blocked at a varnish level following the suggestion here ​http://omninoggin.com/web-development/block-unwanted-spam-bots-using-varnish-vcl/
3. We have increased the amount of CPU slices quince get's to address the steal issue show here ​https://ecodissident.net/munin/webarch.net/quince.webarch.net/cpu.html

[chris]

Kiwi has been switched off.