This isn’t an issue if we are writing code in ArcGIS Pro (although Esri does recommend using a version of Pro greater than 1.4) because we are already using 64-bit, but if you were planning on using Desktop as well, then you would need to use ArcGIS Server 10.5 (or greater) or ArcGIS Desktop with Background Geoprocessing (64-bit). Even if all of the feature classes are independent you can only write them to the FGDB one at a time. That problem is magnified if you have an FGDB and you’re trying to write many feature classes to it at once. You might have seen a version of this problem in arcpy previously if you tried to modify a feature class in Python that was open in ArcGIS. That is because file geodatabases and GRID raster types do not support concurrent writing – that is, only one process can write to them at a time. These data formats can often cause schema locking or synchronization issues. Avoid writing to file geodatabase (FGDB) data types and GRID raster data types.Use “in_memory“ workspaces to store temporary results because as noted earlier memory is faster than disk.There are a number of caveats or gotchas to using multiprocessing with ArcGIS and it is important to cover them up-front because they affect the ways in which we can write our code.Įsri describe a number of best practices for multiprocessing with arcpy. Now that we have completed a non-ArcGIS parallel processing exercise, let's look at a couple of examples using ArcGIS functions.