isabella232 / ulimit-release

BOSH Release to increase max open files for co-located jobs

ulimit release

A BOSH release which mimics the function of ulimit

0. Usage

Upload release to director.

Set properties in manifest:

properties:
  nofile:
    soft: 16384
    hard: 16384

Inner workings & Bugs

Only works for the ulimit property "open files".

Creates /etc/security/limits.d/62-ulimit.conf.

Dynamically adjust monit's "Max open files".

This runs as a pre-start script.

Fixes: Accept error: accept tcp [::]:80: accept4: too many open files.

Defaults to 16384/16384 soft/hard limit for all users.

This was tested on Ubuntu and CentOS stemcells.

This release has 2 components:

1. A pre-start executable (pivotal_prlimit, a small C program which uses prlimit(2)) which modifies the ulimit of the running monit process. monit, as it forks sub-processes (i.e. as it starts jobs), will pass along the updated ulimits (max number of open files). This makes sure the ulimit is set on initial deployment.

2. A template which creates /etc/security/limits.d/62-ulimit.conf which sets the ulimit on reboot (pre-start scripts are not run on reboot).