Dmitry Tkach <dmitry(at)openratings(dot)com> writes:
> Well ... *today* there seem to be files between 0000 and 00EC
> Is that range supposed to stay the same or does it vary?
It will vary, but not quickly --- each file represents 1 million
transactions.
If the problem is erratic with VACUUM or SELECT COUNT(*), then the
only speculation I have is flaky hardware: you must be reading different
xids from the table at different times.
regards, tom lane