I’m running ZOS-API with Python, using multiprocessing and each process seems to try use for temporary file as much as tens of GB.

Hi Johnny,

I’m not sure if you’re saving ZRD files but these tend to be the biggest files OpticStudio produces (ZBF files can also be large, but typically not 10’s of Gb).

In non-sequential mode, when saving a ZRD file, OpticStudio first writes this to the %TEMP% folder as Mark mentioned and then after the ray trace is finished, then the ZRD is copied to the final location.  The few options I can think of is:

1. Change the %TEMP% folder location (Control Panel > System > Advanced > Environment Variables).  This will affect all programs on your computer so you should be careful with this option.
2. Modify your multiprocessing scripts to either wait for your previous simulation to finish or to monitor the free space on the C: drive and only spin up a new process if there is enough free space
3. If you are saving ZRD files, make sure you have Compressed Basic Data (CBD).  This uses floats (8 digits) rather about doubles (16 digits) and only saves a subset of data (see Help Files), but it saves enough data to fully reproduce any Detector Rectangle image including incoherent, coherent, radiance & you can use filter strings like normal.