We hit out of disc space errors way too often while working in Katello and I can imagine there will be users hitting the similar issues. The problem is sync can be quite long and we should maybe report this in advance to the user. My request is to implement disc size check before starting downloading rpms or iso files (or where possible) and have an option to disable this behavior. By default it should be switched on.
Having just gone through a case where I ran out of disk space, I'm attaching the tracebacks found on pulp.log and messages log in case it may provide useful information.
Created attachment 573348 [details] pulp.log Python traceback from pulp.log
Created attachment 573349 [details] /var/log/messages /var/log/messages
I do not think it is possible for Pulp to predict running out of disk space, especially since these items are being stored in a database. When the disk is full, it is Mongo, not Pulp that crashes. Pulp correctly responds that it cannot connect to the database. I am closing for now, please feel free to reopen if I missed something.