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Date: Mon, 15 Dec 2003 20:36:23 +0200 (EET)
From: Taavi Talvik <taavi@uninet.ee>
To: Robert Watson <rwatson@freebsd.org>
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cc: freebsd-hackers@freebsd.org
Subject: Re: general load balancing issues
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On Mon, 15 Dec 2003, Robert Watson wrote:

> When setting up load balancing with state, one of the hardest things is
> making sure the solution isn't slower than the original, and the details
> of the local installation are often relevant.  If there are frequent state
> queries, going to a backend database can make things slower.  If they're
> infrequent, and enough of the work can happen on the web server, it can
> make things a lot faster (and it's much easier to manage than many other
> solutions, since it "just works").

I would recommend look at Eddie: http://eddie.sourceforge.net/
It allows runtime addition both front end and back end
servers. Preserves state over failures.

Written in Erlang, using dsitributed database system called mnesia. Mnesia
is written for Telecom applications whose usually have soft real-time
requirements. Optimised towards frequent queries (local caching etc.) and
less frequent distributed database updates.

Alteon (part of Nortel today) Webserver load balancer and SSL accelator
products are probably based on Eddie.

best regards,
taavi