Thread: Too many Open files error for postgres

Too many Open files error for postgres

From
"Geo P.C."
Date:

In Ubuntu 14.04 server on a JAVA Application we are getting Too many Open files error for postgres.

We set the following in /etc/security/limits.conf

* soft nofile 16384
* hard nofile 16384
root soft nofile 16384
root hard  nofile 16384
postgres soft nofile 16384
postgres hard  nofile 16384


Also set the following in /etc/sysctl.conf

kern.maxfiles=20480
kern.maxfilesperproc=18000



Also please see the following results while running as postgres user:

-> ulimit -Hn
16384

-> ulimit -Sn
16384


-> cat /proc/sys/fs/file-max
100268



After restarting the server and checking the ulimit for postgres its 16384 But while checking the limit for opened files under postgres process its still 1024 and 4096

# cat /proc/1072/limits

Max open files            1024                 4096                 files


When we restart postgres services it got changed to

 
#cat /proc/1759/limits
Max open files            16384                16384                files



But it seems its snot affected because still we are getting Too many Open files error. So can anyone please guide me.

Thanks
Geo

Re: Too many Open files error for postgres

From
Tom Lane
Date:
"Geo P.C." <pcgeopc@gmail.com> writes:
> In Ubuntu 14.04 server on a JAVA Application we are getting Too many Open
> files error for postgres.

How many server processes are you trying to use?  I suspect you are
hitting the system-wide file table limit not the per-process limit.
Best answer might be to decrease PG's max_files_per_process setting
rather than try to persuade the kernel to increase its limit.

            regards, tom lane


Re: Too many Open files error for postgres

From
"Geo P.C."
Date:
Thanks a lot.. We are able to fix the issue with it by reducing max_files_per_process to 500 from default 1000..

This paramater "Sets the maximum number of simultaneously open files allowed to each server subprocess". So in postgres it means it reduces the number of open files limit. If possible can you please refine what it actually does?

On Tue, Jun 21, 2016 at 7:39 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
"Geo P.C." <pcgeopc@gmail.com> writes:
> In Ubuntu 14.04 server on a JAVA Application we are getting Too many Open
> files error for postgres.

How many server processes are you trying to use?  I suspect you are
hitting the system-wide file table limit not the per-process limit.
Best answer might be to decrease PG's max_files_per_process setting
rather than try to persuade the kernel to increase its limit.

                        regards, tom lane