Frequent threading lockup when using rbd

Recently glance_store can lock up while copying an image to an RBD store. This manifests in CI with the following tempest failure:

Traceback (most recent call last):
  File "/opt/stack/tempest/tempest/api/image/v2/test_images.py", line 102, in test_image_glance_direct_import
    waiters.wait_for_image_imported_to_stores(self.client, image_id)
  File "/opt/stack/tempest/tempest/common/waiters.py", line 272, in wait_for_image_imported_to_stores
    raise exc_cls(message)
tempest.lib.exceptions.TimeoutException: Request timed out
Details: (ImportImagesTest:test_image_glance_direct_import) Image 4a36ddf9-5f8c-42f8-821e-7e812d59f6dd failed to import on stores:

The following traceback can be found in the glance API logs when this happens:

May 18 00:03:54.307045 np0034059457 <email address hidden>[109619]: Traceback (most recent call last):
May 18 00:03:54.307045 np0034059457 <email address hidden>[109619]: File "/usr/local/lib/python3.10/dist-packages/eventlet/hubs/hub.py", line 476, in fire_timers
May 18 00:03:54.307045 np0034059457 <email address hidden>[109619]: timer()
May 18 00:03:54.307045 np0034059457 <email address hidden>[109619]: File "/usr/local/lib/python3.10/dist-packages/eventlet/hubs/timer.py", line 59, in __call__
May 18 00:03:54.307045 np0034059457 <email address hidden>[109619]: cb(*args, **kw)
May 18 00:03:54.307045 np0034059457 <email address hidden>[109619]: File "/usr/local/lib/python3.10/dist-packages/eventlet/event.py", line 175, in _do_send
May 18 00:03:54.307045 np0034059457 <email address hidden>[109619]: waiter.switch(result)
May 18 00:03:54.307750 np0034059457 <email address hidden>[109619]: greenlet.error: cannot switch to a different thread