12 hour lag, DNS caching ignores TTL
At 12 hours uptime, with div0-stable, master, and 0.8.2, a number of frames reach the 100ms maximum. It occurs over a period of about 40 mins and the intervals are a multiple of 2 minutes (timing below not entirely accurate due to polling and externally counted match time).
The status timing: lines show ~double CPU utilisation when it occurs, but the OS does not see any increase, as DP is blocked by waiting for a DNS query that can take up to 1600ms to complete in my part of the world.
It will reoccur ~12 hours after the last time it stopped, as DP caches the DNS responses for 12 hours, regardless of TTL.
It makes no difference if the map changes or not, or if any players have joined. It's rubbish to play on the server when this is happening.
I have successfully worked around it with a script that refreshes a local cache of A and AAAA records for this list of domains: stats.xonotic.org dpmaster.deathmask.net dpmaster.tchr.no ghdigital.com
[17:45:51] -*- BV has big trouble on dm_silentsiege after 600s: 37.9% CPU, 28.47% lost, offset avg 0.6ms, max 100.0ms, sdev 6.8ms
[17:47:52] -*- BV has big trouble on dm_silentsiege after 721s: 31.8% CPU, 22.00% lost, offset avg 0.6ms, max 100.1ms, sdev 6.5ms
[17:49:52] -*- BV has big trouble on dm_silentsiege after 842s: 29.9% CPU, 19.23% lost, offset avg 0.5ms, max 100.1ms, sdev 6.3ms
[17:52:59] -*- BV has big trouble on dm_farewell_laserfun_mod after 122s: 13.2% CPU, 3.92% lost, offset avg 0.5ms, max 100.1ms, sdev 5.8ms
[17:55:00] -*- BV has big trouble on dm_farewell_laserfun_mod after 243s: 11.0% CPU, 1.59% lost, offset avg 0.5ms, max 100.0ms, sdev 5.7ms
[17:59:01] -*- BV has big trouble on dm_farewell_laserfun_mod after 484s: 14.0% CPU, 4.64% lost, offset avg 0.5ms, max 100.0ms, sdev 5.8ms
[18:04:57] -*- BV has big trouble on dm_farewell_laserfun_mod after 840s: 13.7% CPU, 4.56% lost, offset avg 0.5ms, max 100.0ms, sdev 5.8ms
[18:10:05] -*- BV has big trouble on dm_gasoline_noteams_02 after 243s: 25.7% CPU, 0.89% lost, offset avg 0.5ms, max 100.0ms, sdev 5.7ms
[18:12:05] -*- BV has big trouble on dm_gasoline_noteams_02 after 363s: 26.4% CPU, 0.82% lost, offset avg 0.5ms, max 100.1ms, sdev 5.7ms
[18:18:06] -*- BV has big trouble on dm_gasoline_noteams_02 after 724s: 31.0% CPU, 7.19% lost, offset avg 0.5ms, max 100.0ms, sdev 5.9ms
[18:23:09] -*- BV has big trouble on dm_fe26 after 122s: 11.4% CPU, 1.67% lost, offset avg 0.5ms, max 100.0ms, sdev 5.7ms