Opening a recovering DB in for read-only access?
Sounds somewhat evil, I know, but I was wondering if it was even
remotely possible with the current design?
The reason: we are contemplating using pg_standy to create a
warm-standby. It would be a bonus if we would run read-only queries
against this DB to take some of the load off or production servers.
We currently use slony to provide warm-standby *and* read-only access,
but pg_standby is a great deal more appealing...especially if there was
some way to do read-only access at the same time.
FWIW, the data would not even need to be completely consistent ... the
kinds of things we are looking at offloading are large summary-type
sequential scans of big tables.
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On Thu, Nov 20, 2008 at 21:45, Philip Warner <pjw@rhyme.com.au> wrote:
Sounds somewhat evil, I know, but I was wondering if it was even
remotely possible with the current design?The reason: we are contemplating using pg_standy to create a
warm-standby. It would be a bonus if we would run read-only queries
against this DB to take some of the load off or production servers.We currently use slony to provide warm-standby *and* read-only access,
but pg_standby is a great deal more appealing...especially if there was
some way to do read-only access at the same time.FWIW, the data would not even need to be completely consistent ... the
kinds of things we are looking at offloading are large summary-type
sequential scans of big tables.
Uhh sounds like you are describing hot standby (currently in the works
for 8.4) see:
http://wiki.postgresql.org/wiki/Hot_Standby
http://archives.postgresql.org/pgsql-hackers/2008-11/msg00005.php
Synchronous replication might also be of interest
http://archives.postgresql.org/pgsql-hackers/2008-11/msg00987.php
Alex Hunsaker wrote
Uhh sounds like you are describing hot standby (currently in the works
for 8.4) see:
Yep. That's exactly what I'm talking about. Thanks for the links!
On Fri, 2008-11-21 at 15:45 +1100, Philip Warner wrote:
Sounds somewhat evil, I know, but I was wondering if it was even
remotely possible with the current design?The reason: we are contemplating using pg_standy to create a
warm-standby. It would be a bonus if we would run read-only queries
against this DB to take some of the load off or production servers.We currently use slony to provide warm-standby *and* read-only access,
but pg_standby is a great deal more appealing...especially if there was
some way to do read-only access at the same time.
Yes, exactly what I'm working on now, currently patch in review.
FWIW, the data would not even need to be completely consistent ... the
kinds of things we are looking at offloading are large summary-type
sequential scans of big tables.
Access to inconsistent data has not been agreed. We will only allow
access to consistent data with this approach.
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