> I have verified that killing the postmaster after a few nextval's
> leaves things in a bad state after restart.
>
> I think I see the problem: in nextval(), the sequence data written to
> the WAL log is different from that written to the data page. Isn't
> that bogus?
It was made to avoid WAL-loging on each nextval call, ie it should work
like OID pre-fetching: value stored in WAL must always "exceed" values
returned by nextval so on the after-crash-restart sequence should be
advanced to value which was never returned by nextval (for non-cycled
sequences). Maybe I made some mistakes in implementation?
Vadim