Re: [COMMITTERS] pgsql: Forbid using pg_xlogfile_name() and pg_xlogfile_name_offset()

On Thu, 2010-04-08 at 16:41 +0900, Fujii Masao wrote:
> >> > Why? The tli of the last WAL record received is always the
> >> > recovery target tli currently.
> >>
> >> True.
> >
> > Only in streaming mode. If you use the current TLI as I have suggested
> > then it will be correct in more cases.
> 
> pg_last_xlog_receive_location() might be executed also after archive
> recovery ends. In this case, using the current tli seems not correct
> because it's always different from the recovery target tli after recovery.

Which is why the code I write says "if (RecoveryInProgress())"

> >> Hmm, currently pg_last_xlog_receive_location() returns the last location
> >>  streamed via streaming replication. Should that be changed so that it
> >> also advances when a WAL segment is restored from archive? It seems
> >> strange that pg_last_xlog_receive_location() can be smaller than
> >> pg_last_xlog_replay_location().
> >
> > Yes, it should be changed.
> 
> Should it advance when WAL file in pg_xlog is read? If not,
> pg_last_xlog_receive_location() can be smaller than
> pg_last_xlog_replay_location().
> 
> And, how far should it advance when WAL file is
> partially-filled for some reasons?

Just make pg_last_xlog_receive_location() do exactly the same thing as
pg_last_xlog_replay_location() when working with files. No need to try
to keep two things exactly in sync.

-- Simon Riggs           www.2ndQuadrant.com