On Wed, 2008-04-30 at 11:29 +0100, Heikki Lin****angas wrote:
> chris.johnson@[EMAIL PROTECTED]
wrote:
> > When using pg_standby to remain in recovery mode on a warm standby
system,
> > if there is a need to perform other actions in coordination with
recovery
> > actions, the -x <auxiliary command> option implemented by this patch
> > enables that coordination. I considered adding the ability to
override the
> > restoreCommand, however by keeping this separate and optional it is
> > possible to force retries of the auxiliary command until successful
and
> > still utilize pg_usleep instead of looping within an external script
or
> > command. And the previous behavior of pg_standby remains unchanged
(other
> > than debug logging and do***enting the option in usage) if the new
option
> > is omitted.
> >
> > I added this feature to help with synchronization of a content
repository
> > consisting of a PostgreSQL db for meta-information and a separate file
> > store for content.
> > The auxiliary command enables forcing an rsync of the file store that
is at
> > least as current as the found WAL segment file's db changes, and
prevents
> > recovery of that WAL file unless the rsync can be performed
successfully.
> >
> > (See attached file: pg_standby.c.diff)
>
> This could be implemented by a "pass-through" restore_command, that
> calls pg_standby, and does the custom action when pg_standby returns
> successfully.
Yes, that's the preferred route for most cases.
pg_standby was designed to be customisable, so if it works for Chris,
thats OK.
After some mulling on this, I'm not sure we need to include this in
pg_standby however. If we did we'd end up having before/after commands
and retry options etc.
--
Simon Riggs
2ndQuadrant http://www.2ndQuadrant.com
--
Sent via pgsql-patches mailing list (pgsql-patches@[EMAIL PROTECTED]
)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-patches
|
