[KLUG Members] Postgres Cluster

[Dirk H Bartley]

> Slony is "Slony-I is a "master to multiple slaves" replication system
> with cascading and failover."
> 
> Still not what I'd call a cluster, but it gives you redundancy.  
> 
> I think if you want a true cluster your options are: Oracle or DB2

I still can't imagine functional true multi master clustering with
adequate locking.  That would mean that each "peer" would have to get an
acknowledgment from each of the other peers that that it has received a
"record 53 of table mytable" is locked.  Then the record would be
modified on the update querried against machine and then all of the
other peers would have to get that update before the unlock could occur.
How does true multimastering servers accomplish thist.  Seems like evan
trivial updates could take quite a while and create possible cascading
locks from hell as multiple users update multiple things.

Dirk