I am using MATLAB 2017a with additional toolboxess i.e. image processing, statistics, parallel processing and cluster computing with a license for 300 workers. The operating system is Windows server 2012 R2 with 1 TB of memory per 25 workers.
For testing I have opened 10 MATLAB sessions, as if 10 different researchers on a HPC centre, and used spmd with 25 workers each. spmd statements are placed strategically after assigning 25 3-band ortho-rect. images to a single 4-dim array. The first spmd...end statement is to create distributed arrays and local parts for the 25 workers and the second spmd...end statement for modelling. Lastly the results are extracted from the composite variables and written to disk.
Question: The question implies that the 10 researchers was assigned to other projects and one researcher has to continue. It will be very cumbersome to open 10 sittings of Matlab because only one parpool can be open per session. With createjob you can create a mjs with the full size of 300 workers and each job access the next available 25 workers.