E2E encryption can encounter ordering issues with high-volume concurrent writes

[plorenz]

If there are high volume concurrent writes the following can happen.

There are two possibilities

1. The encryption stream isn't protected, so it's possible that concurrent writes are getting messed up there.
2. The encryption and the queue are two separate steps so it's possible that write 1 could get encrypted first but queued second, thus causing an ordering issue in the encryption stream.