|Message: Execution Speed and Parameterization||Not Logged In (login)|
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Dear Geant4 experts,
I am experimenting with the DICOM example. I am using Geant4.6.1. I am shooting protons into the CT volume.
The execution speed is around 2 or 3 minutes per event on my 3GHz P4 machine. I can improve the time by increasing the compression (subsample) value, but that makes the result rough.
I am measuring time between RunAction::BeginOfRunAction and RunAction::EndOfRunAction, so as to ignore Geant4 and volume initialization time.
If I set the compression value to 2, the speed improves to about 20 to 30 seconds per event. I wonder why the number of voxels has such a drastic effect on the execution time. It seems that there is a heavy penalty when transfering from one parameterized volume (voxel) to the next.
I have gone over the source code, making trivial improvements here and there, but is there anything I can do, other than parallel processing, to significantly improve the execution speed?
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