Extreme delays when creating parpool in newer releases

I am trying to do some parallel processing and have run into issues when creating the worker pool. When I run the parpool command, even with only 1 worker specified, it will give the message "Starting parallel pool (parpool) using the 'local' profile ...", and then stall. I have waited a couple hours and it still does not complete the process or return an error. Interestingly, I have tried the same command on other versions of MATLAB installed on the same computer and was successful. I timed parpool(12) on the three versions I have and got the following results:

2017b: ~35 seconds

2018a: ~80 seconds

2020b: >2 hours

What could be causing this slow down, and how can I fix it?

My machine has: Windows 10; two Xeon e5-2699 processors with 22 cores each; 512 GB of RAM

[Raymond Norris]

Starting a local pool of 4 workers on my 4 core Windows machine took 90-95s with R2020b. 2+ hours certainly points to an issue (not a norm). A couple of thoughts

• Is MATLAB R2020b installed locally or on a network drive?
• Is the license an individual license or a concurrent license with a central license server?

I would suggest contacting Technical Support ([e-mail]) with this information to help troubleshoot this with you.

[David K]

@Raymond Norris The software is installed locally with a concurrent license server on the network. All versions appear to be using the network license. We've only had the license server less than a year, so this may be my first time attempting parpool while using it.

I'll send support an email with all the info, thanks.