On 12/02/2010 15:20, Henri Gomez wrote: > Hi to all, > > Some times ago, we discuss about mod_jk/cluster and more intelligent > strategy to be use for the dispatching system. > > One point was to get system load informations about the various Tomcat > instances involved in a cluster, to send request to the lowest loaded > Tomcat. > > Hyperic Sigar, http://www.hyperic.com/products/sigar.html, seems to > provide such informations for various OS. > > Could it be interesting to add such 'extension' to Tomcat, so it could > be able to send back to jk/cluster so they could get the best > decisions ? > > New commands could be added to AJP13, as done previously with > cping/cpong, http://tomcat.apache.org/connectors-doc/ajp/ajpv13ext.html. > > What do you think about ?
I like the general idea. My personal favourite in terms of implementation is to pass the information via response headers as it allows interoperability with the widest possible range of front-end load balancers. The info can be passed back with every request or only for requests to a particular URL. Then you get into how you measure load. I don't think that there will be a one size fits all solution. I imagine that it would need to be fairly easy for folks to implement their own load measurements. Using response headers makes that simple to do providing we get the definition of that header format right. Mark --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@tomcat.apache.org For additional commands, e-mail: dev-h...@tomcat.apache.org
