Re: cluster replication with intermezzo

Robert Williams <bob(at)bob(dot)usuhs(dot)mil> writes:
> I'm running postgresql on a two machine
> intermezzo cluster (www.inter-mezzo.org).

This *will* *not* *work*. Period.

> I haven't tested it with a heavy load yet -

Expect data corruption as soon as you exercise it at all.

> I don't thing this should be a problem,
> since as I understand it, table and row
> locking occurs at the postgres backend level
> and lock files are kept in a database table,

No, the locking is all done in shared memory. Since you've got two
postmasters with two separate shared memory blocks, there is no
interlocking between the two sets of backends. There are more problems
here than I can easily enumerate :-(

Now, you could possibly make it work as a hot-failover setup, ie,
one machine can start running a postmaster after the other one crashes.
But two postmasters running simultaneously against the same file set
won't work.

regards, tom lane