I'm using nginx for serving static files and as a proxy for an Erlang IM server. Each user is using two long-polling http connections. OS is ubuntu server.
On peak hours I see:
> sudo more /proc/sys/fs/file-nr
1024 0 38001
On normal hours the number of file descriptors goes below 1024 but it never exceeds 1024. Users reporting on lost connections when I'm hitting the 1024 limit.
Why am I limited by 1024 file descriptors although the root user (erlang), www-data user (nginx) and open TCP connections are lower than 1024 each? Is there some global 1024 limit?
Do I need to use worker_rlimit_nofile with nginx or is it enough to increase the nofile in limits.conf for all users?
Thanks
More info that might be relevant:
> sudo nano /etc/security/limits.conf
...
root hard nofile 30000
root soft nofile 30000
> sudo sysctl fs.file-max
fs.file-max = 38001
> ulimit -a
core file size (blocks, -c) 0
data seg size (kbytes, -d) unlimited
scheduling priority (-e) 0
file size (blocks, -f) unlimited
pending signals (-i) 4160
max locked memory (kbytes, -l) 32
max memory size (kbytes, -m) unlimited
open files (-n) 1024
pipe size (512 bytes, -p) 8
POSIX message queues (bytes, -q) 819200
real-time priority (-r) 0
stack size (kbytes, -s) 8192
cpu time (seconds, -t) unlimited
max user processes (-u) 4160
virtual memory (kbytes, -v) unlimited
file locks (-x) unlimited