Date: Tue, 14 Nov 2006 14:40:03 -0800 (PST)
From: Jeff Frost <jeff@frostconsultingllc.com>
To: Bruce Momjian <bruce@momjian.us>
cc: Chris Browne <cbbrowne@acm.org>, pgsql-docs@postgresql.org
In-Reply-To: <200611142232.kAEMWL901054@momjian.us>
Message-ID: 
 <Pine.LNX.4.64.0611141434020.23695@discord.home.frostconsultingllc.com>
References: <200611142232.kAEMWL901054@momjian.us>
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Subject: Re: [HACKERS] Replication documentation addition

On Tue, 14 Nov 2006, Bruce Momjian wrote:

>>> We had a long discussion about that and felt that recommending
>>> commercial products or even every open source project was too much.  The
>>> idea was that we should reference a web page that has them all mentioned,
>>> but no one has set one up yet.
>>
>> That makes sense, I just hate to see us say something like "Oracle can do
>> this with RAC but PostgreSQL cannot."
>
> Agreed.  I think we would mention any PostgreSQL solution for this, even
> if it is not open source.  We mention solutions as examples in this part
> of the documentation.
>
> 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?

-- 
Jeff Frost, Owner 	<jeff@frostconsultingllc.com>
Frost Consulting, LLC 	http://www.frostconsultingllc.com/
Phone: 650-780-7908	FAX: 650-649-1954