Running Mplus Jobs on Linstat

Mplus is now available on Linstat, the SSCC's Linux computing cluster, where it can use up to 16 cores and much more memory than on Winstat. This can make large Mplus jobs run much more quickly. Running jobs on Linstat is probably easier than you think. If you've never used Linstat before, start by reading the linux essentials section in our guide to research computing.

Linstat is a cluster of of Linux servers. If you log in to "Linstat" you could be assigned to any of the individual servers, which helps spread the load among them. However, our Mplus license only allows us to install it on three servers, Linstat1, Linstat2, and Linstat3. Thus if your goal is to run Mplus you should log in directly to one of these servers rather than just Linstat. Connecting to SSCC Linux Computers using X-Win32 and Connecting to Linstat from a Mac have instructions.

We are also only allowed to have one Mplus job running on each server at a time. If you are told it is currently in use on all three servers we're afraid you'll have to wait. (If this happens to you a lot, let the Help Desk know and we'll look into transferring more licenses from Winstat to Linstat.)

Any files you want to use on Linstat need to be stored on the SSCC's Linux file system. If you're using a Windows computer on the SSCC network, the Z:\ drive is your Linux home directory and the V:\ drive is Linux project space. The Mplus editor is not available for Linux, but you can write your input files using Mplus on Winstat and then save them on Z:\ or V:\. Our Guide to Research Computing will teach you how to organize your files for easy use in Linux programs.

Once everything is set up, running an Mplus program is very easy. Just type:

mplus myinputfile.inp

where myinputfile.inp should be replaced by the actual name of your input file.

You'll see Mplus open several terminal windows. The way Mplus uses multiple cores is unusual in that rather than having the program start additional processes directly, it launches additional terminal sessions that then start additional processes. Unfortunately this means that you need to stay logged in to Linstat the entire time the program is running. Mplus will also continue to write output to your original Linux terminal, so there's no point in running it in the background. Create a new Linstat session if you want to do additional work, but keep in mind you won't be able to start another Mplus job.

Last Revised: 4/26/2016