Allocating processing units to generate simulated diffraction signals used in optical metrology

A computer-readable medium containing computer-executable instructions for allocating processing units of a computer system to generate simulated diffraction signals in optical metrology, comprising instructions for:

• a) obtaining a request for a job to generate simulated diffraction signals using multiple processing units;
• b) determining a number of requested processing units for the job to generate simulated diffraction signals;
• c) determining a number of available processing units;
• d) when the number of requested processing units is greater than the number of available processing units, assigning a number of processing units to generate the simulated diffraction signals that is less than the number of requested processing units;
• e) determining a new number of available processing units;
• f) when the new number of available processing units exceeds the number of available processing units determined in c), re-assigning the job to the new number of available processing units or the number of requested processing units;
• g) if the number of available processing units is less than the number of requested processing units, re-assigning the job to the new number of available processing units;
• and
• h) if the number of available process units is not less than the number of requested processing units, re-assigning the job to the number of requested processing units.

A system for allocating processing units of a computer system to generate simulated diffraction signals in optical metrology, the system comprising:

• a plurality of processing units configured to generate simulated diffraction signals;
• and
• a processor configured to:
• obtain a request for a job to generate simulated diffraction signals using one or more of the plurality of processing units;
• determine a number of requested processing units for the job;
• determine a number of available processing units;
• and
• when the number of requested processing units is greater than the number of available processing units, assign a number of processing units to the job that is less than the number of requested processing units;
• determine a new number of available processing units;
• when the new number of available processing units exceeds the number of available processing units, re-assign the job to the new number of available processing units or the number of requested processing units;
• if the number of available processing units is less than the number of requested processing units, re-assign the job to the new number of available processing units;
• and
• if the number of available process units is not less than the number of requested processing units, re-assign the job to the number of requested processing units.