I'm using least connections with an Alteon on a recently installd system. Least connections, whil eperhaps crude, is one of the most effective methods for load balancing.
The general reason is that over the long haul, it will be putting conenctions onto those mahcines which are discharging their old connections faster. That is usually due to better performance, althoguh not always. We have run into issues with more "intelligent" load balancing that kept pumping up one machine more than others because its CPU load was low. In fact there was a disk issue which kept the machine in a bad IO wait state which was not taken into account, hence most of the connections went to a "slower" machine. In playing aorund with the various types of laod balancing, I came to the conclusion that the KISS principle applied. More intelligent load balancing is probably better, but in all honesty its splitting hairs. If I can get 98% of my connections going to the best machine, why work harder to get to 99%? And also remember, just because it doesn't get to the best machine does not mean it will get done that much faster. Maybe 3 seconds instead of 2? Not worth the effort in most cases. \ IMO if you ever get to the case where a machine is simply way to busy to handle the load, you need to add more hardware. Thats a much better investment instead of trying to squeeze every last drop of performance out of a system, at least for a larger organization where time is money. One caveat on least connections though, it would be nice if it was a weighted least connections average where you could target a percentage of connections to every machine. I've got one J2EE back end system needing to be load balanced now where one machine is a 4 year odl Sun 450 and the other is a newer V880. In an ideal world I want 70% of the traffic to the V880. Least connections will get me close to that, but not all the way. Jeffrey Burgoyne Chief Technology Architect KCSI Keenuh Consulting Services Inc [EMAIL PROTECTED] On Mon, 10 Jan 2005, Stefan Hueneburg wrote: > Hallo, > > Jim Jagielski <[EMAIL PROTECTED]> wrote: > > > I'm currently working on code that extended the lb method > > within the 2.1/2.2 proxy from what is basically a > > weighted request count to also be a weighted > > traffic count (as measured by bytes transferred) > > and a weighted "load" count (as measured by response > > time). The former is further along and the methods > > will be selectable at runtime... This is definitely > > a scratch I'm itching, but before I spend too much > > (additional) time on it, I'd like some feedback > > on whether the concept is one we can all get behind. > > Maybe "least connection count" is also interesting. > > However, on Alteon-LB i experienced some kind of weird load pumping > when i used "least connection" mode. > > Bis dann, > Stefan Hüneburg > -- > easynet GmbH (http://www.de.easynet.net) > System Administrator, Application Services > Harburger Schlossstrasse 1, D-21079 Hamburg > fon: +49-40-77175-526, fax: +49-40-77175-519 >
