Multicore sampling not working on windows machine (rstanarm, brms)



I have problem regarding running models on multiple cores using either rstanarm or brms under windows and R 3.4.3… Running the model (simple regression) with 1 core runs fine but as soon as I what to use multiple cores, the “Viewer” opens, but actually nothing happens.

“Click the Refresh button to see progress of the chains starting worker pid=3408 on localhost:11456 at 15:00:36.757”

Has anyone experienced this problem before? The parallel::detectCores() function correctly identifies 8 cores.

Operating System: Windows
Interface Version: rstanarm 2.17.4
Compiler/Toolkit: RTools 3.4


Did you click on the Refresh button?


yes I did, with no results. R also shows that it is still running showing the “stop” sign and but does not give any results For 1 core running 4 chains only takes a second .

I did this experiment with a very simple model, since I tried to fit a Gaussian process model before using brms and was not sure whether the long waiting time was due to the more complicated model or because of some other problems. Obviously it was the latter.


That usually indicates some sort of a permissions / antivirus thing on Windows that is blocking parallel sampling.


perfect thanks, what was the problem