puzzling parfor error during large calculation

11 views (last 30 days)
Jakob Sievers
Jakob Sievers on 29 Mar 2014
Commented: Rinu on 1 May 2016
Hi there
I am running a large number of differential evolution optimization runs on a 4-parameter problem, for different input control parameters. I am using parfor to speed up things significantly. However I have experienced some weird error instances which, given that I have tested the whole thing as a normal for-loop, suggests that the parallel-toolbox is experiencing problems. The error in question is:
Caught "std::exception" Exception message is:
fl:filesystem:PathNotFound
Error using distcomp.remoteparfor/getCompleteIntervals (line 138)
An unexpected error occurred during PARFOR: Error in remote execution of
remoteParallelFunction : RUNTIME_ERROR
Error in runnested_eddy_Lee_DEparamopt_mainprog (line 23)
parfor ii=1:length(NPop)
Does anyone know what this means? I gather that a file associated with the parallel run is missing but I don't know how to fix that, if that is the case, and google gives me no clues as to the cause/solution of this problem.
Cheers
Jakob

Accepted Answer

Jakob Sievers
Jakob Sievers on 29 Mar 2014
Edited: Jakob Sievers on 29 Mar 2014
I think I may have solved the issue. I dug deep into the optimization code and discovered that it saves a temporary file, and deletes it again following the calculation. Throw that into a parfor loop and the file is created and deleted by separate processes and the whole thing goes wrong. I attached a time-signature to the filename during its creation and the problem seizes to be relevant.
  2 Comments
Rinu
Rinu on 1 May 2016
I had the same problem, and in my case it seems the problem was caused because I open different files using the same filename in every loop and did not close the file before exiting the loop. Using fclose within the loop solves the problem.

Sign in to comment.

More Answers (0)

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!