When is the new version of postgres (8.5) scheduled to be released as the latest stable version?
Thanks, John 2010/1/21 Grzegorz Jaśkiewicz <gryz...@gmail.com> > depends on what sort of replication you are going to use really. > Most are based on triggers. So they have a bit more impact on > performance. As far as locking goes, postgresql is very conservative > with locks, ie - it won't abuse them, unlike for instance mysql. > So I don't know whether you are just worried about performance in > general, or locking in particular. But impact of likes of slony isn't > that big, but obviously once the new version is out - it will be even > less of a problem, since postgresql already produces transactional log > for recovering, and pretty much the same log is going to be used for > replication. > > > 2010/1/21 John Mitchell <mitchellj...@gmail.com>: > > So am I to presume that the current stable version of postgres (before > 8.5) > > does require extra locking? > > > > John > > > > 2010/1/21 Grzegorz Jaśkiewicz <gryz...@gmail.com> > >> > >> On Thu, Jan 21, 2010 at 1:12 PM, John Mitchell <mitchellj...@gmail.com> > >> wrote: > >> > Hi, > >> > > >> > In reading the documentation it states that the SQL dump backup does > not > >> > block other operations on the database while it is working. > >> yes, pg_dump opens serializable transaction thus guarantees data to be > >> the exact snapshot (as opposed to the default isolation level, which > >> is called 'read commited' not without reason). > >> > > >> > I presume that while a restore is occurring that no reads or updates > are > >> > allowed against the restored database. > >> nope, what restoring does, is just running all the commands in the > >> pg_dump (whether it is binary or textual). So as soon as the database > >> is created, it is treated just as any connection, thus allows you to > >> connect and use it. > >> > >> > >> > What locking mechanism is used for Master-Slave Replication? > >> > >> master slave that's introduced in what's to be 9.0 (aka 8.5), uses WAL > >> shipping. So it doesn't require any extra locking. > >> > >> > >> > >> -- > >> GJ > > > > > > > > -- > > John J. Mitchell > > > > > > -- > GJ > -- John J. Mitchell
