Arcpy Parallel Processing w/ Spatial Analyst?

[KevinBell]

I've got to chew through A LOT of (LiDAR) data using spatial analyst functions with python/arcpy, and I'm wondering about how this works on server at 10.1...  If I want to run, say, 24 cores at once, do I need 24 spatial analyst licenses?  Does arcpy run 64 bit on the server?

[BurtMcAlpine]

You will need one spatial license per server, so as long as you are on the same piece of hardware you only need one license.  Arcpy should be 64Bit on server, but i am not 100% sure, but the script would be written the same for 32Bit.  (the script doesn't care 32 vs 64).  Make sure to watch the memory usage trying to process that much data an all available cores.  I would try it on one core and see the peak memory usage and then see how many processes you can safely start at one time without running out of memory and crashing.

Are you going to use python multiprocessing module with Pool or some other module?

[KevinBell]

A previous run on 8 cores was successful via the "embarrassingly parallel" method.  l just launched 8 identical scripts from the cmd line and each seems to do it's work just fine.  I would see a new core jump with each script starting.  I believe that method does require multiple licenses because it's not a single process that is handling it.  I've got an ELA, so it's not a problem.