$ sw_vers ProductName: Mac OS X ProductVersion: 10.11.4 BuildVersion: 15E65 $ man purge | cat purge(8) BSD System Manager's Manual purge(8) NAME purge -- force disk cache to be purged (flushed and emptied) SYNOPSIS purge DESCRIPTION Purge can be used to approximate initial boot conditions with a cold disk buffer cache for performance analysis. It does not affect anonymous mem- ory that has been al