Received: from localhost (uranus.hub.org [200.46.204.60]) by postgresql.org (Postfix) with ESMTP id DE4D99FA219 for ; Mon, 20 Nov 2006 11:02:08 -0400 (AST) Received: from postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.204.60]) (amavisd-new, port 10024) with ESMTP id 57670-03 for ; Mon, 20 Nov 2006 11:02:07 -0400 (AST) X-Greylist: from auto-whitelisted by SQLgrey- Received: from momjian.us (momjian.us [70.90.9.53]) by postgresql.org (Postfix) with ESMTP id 86A669FA1DB for ; Mon, 20 Nov 2006 11:02:06 -0400 (AST) Received: (from bruce@localhost) by momjian.us (8.11.6/8.11.6) id kAKF1jT19581; Mon, 20 Nov 2006 10:01:45 -0500 (EST) From: Bruce Momjian Message-Id: <200611201501.kAKF1jT19581@momjian.us> Subject: Re: [HACKERS] Replication documentation addition In-Reply-To: To: Jim Nasby Date: Mon, 20 Nov 2006 10:01:45 -0500 (EST) CC: Jeff Frost , Chris Browne , pgsql-docs@postgresql.org X-Mailer: ELM [version 2.4ME+ PL123] MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="US-ASCII" X-Virus-Scanned: Maia Mailguard 1.0.1 X-Archive-Number: 200611/37 X-Sequence-Number: 3871 Jim Nasby wrote: > On Nov 14, 2006, at 5:11 PM, Bruce Momjian wrote: > > Basically, when you are broadcasting outside the server, you are > > broadcasting SQL queries, and those queries do not have information > > about non-deterministic functions and have issues with universal > > commits > > on all node. > > That's true of simple query broadcasting (ie: pgpool), but not true > of Continuent/Sequoia. Continuent's software adds a lot of additional > features on top of simple query broadcasting, making it far more > robust than simply spewing queries out to every node in the cluster. > You still have to be very careful with how you use it, but not nearly > as much as with simpler solutions. Yes, I have heard that Continuent/Sequoia has a process running on each server that deals with many of the problems with broadcasting. Not sure how I should work that into the documentation. In fact, based on our description, the improvements Continuent/Sequoia made are probably clearer. -- Bruce Momjian bruce@momjian.us EnterpriseDB http://www.enterprisedb.com + If your life is a hard drive, Christ can be your backup. +