Purging will remove an object from Fedora as well as from the search engine but it will not remove the metadata and object files stored on the Credo server. To purge an object from Credo:
Files will be purged once an hour, right before the ingest runs. Files are purged 30 at a time so if there are more than 30, the next batch will wait until the next purge runs.
Like with the ingest process, the files added to purge do not have to be actual metadata files, just files with named with the PID you want to purge and no file extension.