From: Bruce Momjian <bruce@momjian.us>
Message-Id: <200611142243.kAEMhZf02180@momjian.us>
Subject: Re: [HACKERS] Replication documentation addition
In-Reply-To: 
 <Pine.LNX.4.64.0611141434020.23695@discord.home.frostconsultingllc.com>
To: Jeff Frost <jeff@frostconsultingllc.com>
Date: Tue, 14 Nov 2006 17:43:35 -0500 (EST)
CC: Chris Browne <cbbrowne@acm.org>, pgsql-docs@postgresql.org
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Jeff Frost wrote:
> > FYI, as far as I know, Continuent's solution is "Query Broadcast Load
> > Balancing", not clustering.
> 
> I would speculate that your terminology is slightly more accurate than mine. 
> The do query broadcast, but they also do a bit more with it than that as they 
> evaluate many of the non deterministic write queries on a particular server 
> and update the broadcast query so each db gets the same value.
> 
> I guess middleware of this sort automatically ends up in the query broadcast 
> category.  It just sounds awfully similar to the description of cluster for 
> load balancing:
> 
> In clustering, each server can accept write requests, and these write requests 
> are broadcast from the original server to all other servers before each 
> transaction commits.
> 
> I guess it's kind of a fine line how it gets defined?

Hmmm.  Interesting.  Does anyone else have details or an opinion on
this?  The fact that there is something sitting above the servers seems
to be the defining issue of calling it query broadcast.

-- 
  Bruce Momjian   bruce@momjian.us
  EnterpriseDB    http://www.enterprisedb.com

  + If your life is a hard drive, Christ can be your backup. +