Re: pg_start_backup and pg_stop_backup Re: Re: [COMMITTERS] pgsql: Make CheckRequiredParameterValues() depend upon correct

* Kevin Grittner <Kevin(dot)Grittner(at)wicourts(dot)gov> [100428 15:51]:

> > I don't personally care about streaming replication replaying WAL
> > as it comes, or running queries in recovery...
>
> I'm with you that far, but I wouldn't want the sender to wait for
> remote persistence.

I remember a presentation at pgcon a while ago, it was probaly Fujii
(from NTT?) about their log streaming, and at that time, they talked
about different "sync" options... So I'ld love to be able to have
comits be:
async (like current option)
local wal sync (like current)
local wal sync + walsender sent
local wal sync + walsender confirmed

And ideally, the "walsender sent/confirmed" would even allow making sure
it was sent/confirmed to $X connections... I want to be able to
guarantee it's on 2 machines, not that if my slave was connected it
would be on there, but something happened and my "slave"
has disconnected, so it's only got local WAL...

And then on whatever "tool" is receiving the log streaming, it can be
set to confirm when either:
received buffer
write buffer to file
write buffer to file + sync
write buffer to file + sync + replay

That should give you all the sync levels they talked about in their
presentation...

--
Aidan Van Dyk Create like a god,
aidan(at)highrise(dot)ca command like a king,
http://www.highrise.ca/ work like a slave.