On Thu, Oct 27, 2011 at 16:54, Tom Lane <t...@sss.pgh.pa.us> wrote: > Magnus Hagander <mag...@hagander.net> writes: >> On Thu, Oct 27, 2011 at 13:19, Heikki Linnakangas >> <heikki.linnakan...@enterprisedb.com> wrote: >>> On 27.10.2011 14:09, Fujii Masao wrote: >>>> Yes. But that sounds unuserfriendly. Padding the WAL file manually >>>> is easy-to-do for a user? > >> I'd definitely want to avoid anything that requires pg_receivexlog to >> actually *parse* the WAL. That'll make it way more complex than I'd >> like. > > What parsing? Just pad to 16MB with zeroes. In fact, I think the
I'm just sayihng that *if* parsing is required, it would be bad. > receiver should just create the file that size to start with, and then > write received data into it, much like normal WAL creation does. So when pg_receivexlog starts up, how would it know if the last file represents a completed file, or a half-full file, without actually parsing it? It could be a 16Mb file with 10 bytes of valid data, or a complete file with 16Mb of valid data. We could always ask for a retransmit of the whole file, but if that file is gone on the master, we won't be able to do that, and will error out in a situation that's not actually an error. Though I guess if we leave the file as .partial up until this point (per my other patch just posted), I guess this doesn't actually apply - if the file is called .partial, we'll overwrite into it. If it's not, then we assume it's a complete segment. -- Magnus Hagander Me: http://www.hagander.net/ Work: http://www.redpill-linpro.com/ -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
