might be easier if you have rights to invoke perfmon on the server, or know an administrator who has.
Of course between steps you can get the total space used by objects in your work library
proc datasets details; run;
reveals the data, but I find no sashelp.vxxxxxx providing the info so you would need to trap the table through ODS OUTPUT
However, it won't reveal the peak usage that happens during a step - e.g. when
proc sql performs a cartesian join before grouping results
or proc means needs to summarise on disk