I am running Propka3 on AlphaFold structure AF-O43463-F1-model_v4 from Uniprot (https://alphafold.ebi.ac.uk/download > Homo sapiens).
When running with default parameters the program executes in under 1 second.
When running with the -d (details) flag it runs for (so far) 20+ minutes and has consumed 340+ GB of memory.