Socket accept - “Too many open files”

Question

I am working on a school project where I had to write a multi-threaded server, and now I am comparing it to apache by running some tests against it. I am using autobench to

Answer 1

Similar issue on Ubuntu 18 on vsphere. The cause - Config file nginx.conf contains too many log files and sockets. Sockets are treated as files in Linux. When nginx -s reload or sudo service nginx start/restart, the Too many open files error appeared in error.log.

NGINX worker processes were launched by NGINX user. Ulimit (soft and hard) for nginx user was 65536. The ulimit and setting limits.conf did not work.

The rlimit setting in nginx.conf did not help either: worker_rlimit_nofile 65536;

The solution that worked was:

$ mkdir -p /etc/systemd/system/nginx.service.d
$ nano /etc/systemd/system/nginx.service.d/nginx.conf
    [Service]
    LimitNOFILE=30000
$ systemctl daemon-reload
$ systemctl restart nginx.service