Re: pg_xlogdump and .partial files

On Mon, Sep 28, 2015 at 9:47 AM, Peter Eisentraut <peter_e@gmx.net> wrote:
> The pg_xlogdump man page states that it cannot read .partial WAL files
> and that they need to be renamed.  It seems to me with about the same
> number of lines we could just make it accept those files, no?

FWIW, the discussion has happened here:
http://www.postgresql.org/message-id/CAB7nPqS_X5-M+S9yo_xd7OxWq1ETVwV-1TsjUqNOVQYYAztReA@mail.gmail.com
In short, I was under the impression that this was not worth it, and I
still am under this impression knowing that this is not a common use
case.

Now, and I imagine that this is actually what is disturbing for the
user: we could allow the definition of a .partial file as an end
segment. We would need to be careful though in XLogDumpXLogRead when
doing the segment switch when the last segment is being read. As
pg_xlogdump does not handle timeline jumps this would be useful to
allow the user to have a look at the segments of a previous timeline
up to the point the promoted standby has switched to, particularly if
the .partial file, archived by a promoted standby, and its complete
version, archived by old master are present at the same position.
Still this seems like a very narrow use-case to me, so opinions are
welcome.
Regards,
-- 
Michael