According to https://www.perforce.com/perforce/r16.1/manuals/cmdref/p4_client.html , a client can be optionally set to type readonly to avoid automated builds fragmenting and bloating the server's db.have file. There are other benefits to using readonly-type clients - from what I understand the readonly client db files are not journaled so they won't be transmitted between replicas when they change.

Using readonly clients for our Jenkins builds would likely solve an issue we have where one of our replicas in France gets hammered with nightly builds which makes our replica in the US completely unusable for an hour or more due to the db.have file being locked while our replica catches up with all of the pointless updates from the French replica.