[MapProxy] Seeding stops in between seeding tasks

["Sven Möller [Kober-Kümmerly+Frey]"]

Dear mailing list,

We are using a dockerized MapProxy 1.14.0 (same happened in 1.13.0) and are experiencing complete halts in between seeding tasks within a seeding configuration. When this occurs the previous seeding task ends with progress of 100% like so

...
[10:18:24] 17  63.43% 1037097.59977, 6232369.53826, 1041989.56958, 6237261.50807 (780096 tiles)
[10:18:54] 17  67.22% 1100693.20731, 6163881.96092, 1105585.17712, 6168773.93073 (803136 tiles)
[10:19:24] 17  76.99% 1262128.21104, 6129638.17224, 1267020.18086, 6134530.14206 (829440 tiles)
[10:19:37] 17 100.00% 665690.55494, 6047171.27030, 1672018.75171, 7327009.86179 (839616 tiles)

and the next task is never started. This does not happen at a specific seeding task or seeding configuration but can happen randomly in between any seeding tasks. Sometimes it does, sometimes it doesn’t. In all these configurations we seed from a self-hosted WMS service which is still functional and not receiving any further requests from the seeder. Also I can observe via “ps -ef” that all mapproxy seed workers are defunctional:

root         274       8  7 10:02 ?        00:03:01 [mapproxy-seed] <defunct>

Any ideas on what could be the cause of this issue and how to debug it?

Kind regards,
Sven Möller