Gunicorn - "Resource temporarily unavailable"
Are you seeing this error in your logs while your server is under high load?:
[error] 10#0: *14843 connect() to unix:/tmp/gunicorn.sock failed (11: Resource temporarily unavailable) while connecting to upstream, client: 96.44.145.186, server: , request: "GET / HTTP/1.0", upstream: "http://unix:/tmp/gunicorn.sock:/", host: "45.55.46.84"
I ended up making an example dockerfile with nginx + gunicorn + flask to reproduce this problem: https://github.com/pawl/somaxconn_test
Bumping the net.core.somaxconn setting ended up fixing it.