So far I have been experimenting with uWSGI to replace a lot of kludgy server code that builds and does setup for Python wsgi applications under supervise. I am running dozens of these small projects (Django, Flask, other) at once.
Currently I am running in Virtualhost mode and I allow NGINX to basically invoke applications at will. However, it seems the reload feature "touch-reload" is meant for a specific file.
Is there a way to use "touch-reload" to monitor the module that is running either by specifying it per site or automatically? Or is there a way to allow touch-reload to be configured per application?
I have also looked at emperor mode, which seems like it could be a slightly less awesome substitute but I am not sure if my use case would cause dozens if not hundreds of processes to spawn. I like the virtualhost mode because it essentially shares a pool of workers over all of the applications, this seems most efficient to me.
<uwsgi> <vhost-host/> <master/> <gid>www-data</gid> <uid>www-data</uid> <catch-exceptions/> <socket>/var/tmp/uwsgi.sock</socket> <chmod-socket/> <idle>300</idle> <processes>6</processes> <no-orphans/> <enable-threads/> <reload-mercy>5</reload-mercy> <threads>10</threads> <no-default-app/> <touch-reload/> <!-- <reload-on-rss>128</reload-on-rss> Reload at 128MB of RSS (memory usage) --> </uwsgi>
After doing some research about how uWSGI handles shutting down idle workers, I think I will need the emperor mode after all.
What I am trying to do is let seldom used applications take no resources and oft used applications take more resources. I am trying to do that while maintaining a hosting deployment as simple as PHP-FPM. The virtual mode achieves this but seems to shut down all workers only after all applications have been idle, which isn't useful if any app receives a steady stream of traffic. I would love to be corrected on this issue if it's untrue.
The downside to going with emperor mode is that I will have to make socket files and config files for each application (blech!). I would still like to know if it's possible to implement per application reloading as mentioned above though.