Recommended ulimit settings for linux

Products

• CA Automic Workload Automation - Automation Engine

Issue/Introduction

What are the recommended ulimit settings for Linux/Unix 

Recommended ulimit settings for linux

Kind of problems:
*) Too many open files
*) Out of memory

Environment

Automation Engine 12.x,21.x,24.x

OS: Linux/Unix

Cause

For the following kind of error that prevented the JWP process from creating new threads and processing any request:

U00045014 Exception 'java.lang.OutOfMemoryError: "unable to create native thread: possibly out of memory or process/resource limits reached"' at 'java.lang.Thread.start0()'.

The reason being that ulimit -s (maximum number of user processes) was set to a very low value (1024) and all the AE processes and several tools using Java API were all launched under the same user.

Resolution

Set the main ulimit properties to unlimited:
We recommend these settings for all linux/unix agents.
Data, memory, nofiles and stack should be set to unlimited, the user uprocesses should be set to a high value (such as 8192) as JWP and JCP are multithreaded processes.

ulimit -d unlimited
ulimit -m unlimited
ulimit -n unlimited
ulimit -s unlimited
ulimit -u unlimited

These settings are also recommended from IBM for java based applications.