How to set a global nofile limit to avoid "many open files" error?

Question

I have a websocket service. it's strage that have error:"too many open files", but i have set the system configure:

/etc/security/limits.conf
*               soft    nofile          65000
*               hard    nofile          65000

/etc/sysctl.conf
net.ipv4.ip_local_port_range = 1024 65000

ulimit -n
//output 6500

So i think my system configure it's right.

My service is manage by supervisor, it's possible supervisor limits?

check process start by supervisor:

cat /proc/815/limits
Max open files            1024                 4096                 files 

check process manual start:

cat /proc/900/limits
Max open files            65000                 65000                 files 

The reason is used supervisor manage serivce. if i restart supervisor and restart child process, it's "max open files" ok(65000) but wrong(1024) when reboot system supervisor automatically start.

May be supervisor start level is too high and system configure does not work when supervisor start?

edit:

system: ubuntu 12.04 64bit

It's not supervisor problem, all process auto start after system reboot are not use system configure(max open files=1024), but restart it's ok.

update

Maybe the problem is:

• https://bugs.launchpad.net/ubuntu/+source/upstart/+bug/938669
• http://bryanmarty.com/blog/2012/02/10/setting-nofile-limit-upstart/
• Increase max open files for Ubuntu/Upstart (initctl)

Now the question is, how to set a global nofile limit because i don't want to set nofile limit in every upstart script which i need.

Answer 1

Fixed this issue by setting the limits for all users in the file :

$ cat /etc/security/limits.d/custom.conf
* hard nofile 550000
* soft nofile 550000

REBOOT THE SERVER after setting the limits.

VERY IMPORTANT: The /etc/security/limits.d/ folder contains user specific limits. In my case hadoop 2 (cloudera) related limits. These user specific limits would override the global limits so if your limits are not being applied, be sure to check the user specific limits in the folder /etc/security/limits.d/ and in the file /etc/security/limits.conf.

CAUTION: Setting user specific limits is the way to go in all cases. Setting the global (*) limit should be avoided. In my case it was an isolated environment and just needed to eliminate file limits issue from my experiment.

Hope this saves someone some hair - as I spent too much time pulling my hair out chunk by chunk!