On FreeBSD, this test showed two problems: (1) reordering problems
based on writing the predicate, event, and end-of-data updates into a
single file, (2) a race condition based on printing the entirety of
the table description argument in update events. The description
contains the destination table, and its content at the time an update
event gets processed isn't deterministic: depending on the number
of updates the reader thread has sent, the table will contain a
varying number of entries.
