Recommended System Limits for Macintosh and Linux

If you use a UNIX^® system (Linux^® or Macintosh), it is recommended that you adjust your operating system limits. Check and set limits with the ulimit or limit command, depending on your installation. Note that these commands might require root access.

System Limit	Recommended Value	Option (ulimit)	Option (limit)
Maximum number of user processes	23741	-u	maxproc
Maximum number of open file descriptors	4096	-n	descriptors

For example, these commands set the maximum number of user processes.

ulimit -u 23741
limit maxproc 23741

Changing a limit inside a shell affects only that shell and any subsequent MATLAB^® sessions you start there. To make this setting persistent system-wide, you must modify the relevant file.

• Linux – Modify the limits.conf file.

• Macintosh – Modify plist files, such as limit.maxfiles.plist and limit.maxproc.plist.

For assistance, check with your system administrator.

For more information on ulimit, limit, or limits.conf, see their man pages.

Without these settings, large parallel pools can error, hang, or lose workers during creation. These problems occur when MATLAB attempts to create more user processes or file handles than your operating system allows.

If you use a cluster of machines, you must set the maximum number of user processes for each machine.

Related Topics

• What Is a Parallel Pool?