"Warning: Unable to load Toolbox Path Cache" during parallelization

I am running multiple instances of C-code in parallel on Ubuntu. The C-code starts up matlab, calls a script, then closes. When running many at once (~8), I get the following error intermittently:

Warning: Unable to load Toolbox Path Cache
/home/chuck/.matlab/R2018a/toolbox_cache-9.4.0-2328427802-glnxa64.xml. The
cache file is not in the correct format. It will be regenerated upon quitting
MATLAB. 

I have found that unchecking "Update Toolbox Path Cache" per this post will prevent the warning from occuring, but that it slows down each Matlab call.

Is there a way to prevent this warning other than not using the cache?

[rana afaq]

You can try to remove this error by updating the cache and cache file. Open MATLAB then Go for HOME option, you will see the PREFERENCE option in ENVIRONMENT SECTION. Choose General In MATLAB, The General Preference pane will be diplayed there. You will see the " UPDATE TOOLBOX PATH CACHE " click on it and Press Ok .

[moayed mohamed]

Thank U dr rana afaq

Answer 1

[Jan]

If the path cache is updated by multiple threads, it is likely, that one thread tries to read the file, while it is re-created by another thread. This is a standard problem of multi-threading. This ould be solved, if Matlab creates a file lock before one threads accesses the file, but as long as this is not implemented, disable the updates of the Toolbox Path Cache.