Ceph » CephFS

Inspecting the test code:

 # unmount any cephfs mounts
 for i in range(0, self.CLIENTS_REQUIRED):
   self.mounts[i].umount_wait()
 sessions = self._session_list()
 self.assertLessEqual(len(sessions), 1) # maybe mgr is already mounted

At this point, there may be 0 or 1 sessions in the list.

 # Get the mgr to definitely mount cephfs
 subvolume = self._gen_subvol_name()
 self._fs_cmd("subvolume", "create", self.volname, subvolume)
 sessions = self._session_list()
 self.assertEqual(len(sessions), 1)

If at the previous step we may have 1 session in list, and this one adds another session, maybe the assert should be modified?

Igor Golikov wrote in #note-2:

Inspecting the test code:
[...]

At this point, there may be 0 or 1 sessions in the list.

[...]

If at the previous step we may have 1 session in list, and this one adds another session, maybe the assert should be modified?

If there is a session, the mgr would reuse that, unless that logic has changes, of course. This is done here: https://github.com/ceph/ceph/blob/main/src/pybind/mgr/mgr_util.py#L315

A connection pool of cephfs clients is maintained and the mgr plugin choses a connection which has minimum ops in progress (or spins up a new one). See: https://github.com/ceph/ceph/blob/main/src/pybind/mgr/mgr_util.py#L238