Timeouts and gunicorn configuration

[aulemahal]

Moving discussion from Ouranosinc/raven#391 to here.

Long requests cause timeouts in the current configuration of finch using gunicorn.

According to the doc (https://docs.gunicorn.org/en/latest/design.html#choosing-a-worker-type), we shouldn't be using the sync workers for "Applications making long blocking calls (Ie, external web services)", which is exactly was finch is all about.

2 solutions tried (in the gunicorn command) and resolved the timeout problem :

• Use -t 0 to disable timeouts entirely.
• Use -k gthread to use an asynchronous worker.

AFAIU, the timeout is still counted for async worker, but only if they are idle.

I'm not sure of the implication of either solutions.

[huard]

@cjauvin Possibly relevant to your current analysis.