httpd-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Mladen Turk <mt...@apache.org>
Subject Re: Working on some load balancing methods
Date Sat, 08 Jan 2005 08:28:40 GMT
Jim Jagielski 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).

Sure, the general idea was to allow different lb methods.
I've started to collect the transferred for various
protocols to be able to do a traffic balancing.
You have that params already present in the shared
memory, so making sure we collect the real values
transferred is a first step thought.

I'm also working on extending the load balancer to
a domain clustering model for grouping cluster nodes
in groups to lower the session replication transfer
for backends that offer the session replication.

> 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.
> 

+1.

> I am also toying with the idea of supporting
> a CPU load method when the origin servers are
> Apache via a custom response header...
> 

Well, that'll be awesome to achieve, not only to
dynamically update the balancer node member, but
to safely remove it from the cluster in a two
phase process if the backend 'decides' so.
Right now this is possible using 'balancer-handler',
so the dynamic logic is there already.

The header processing should also allow to
discover the topology dynamically (there is
already PROXY_DYNAMIC_BALANCER_LIMIT meant to
be used for that).
I'm not sure if this will be possible on all
protocols but we have a long-standing AJP13
extension proposal that if implemented will
allow that kind of operation.
http://jakarta.apache.org/tomcat/connectors-doc/common/ajpv13ext.html

Regards,
Mladen.

Mime
View raw message