Ok, makes sense. The usecase is quite specific as the connection rate is really low (max 5 per minutes) and the cpu usage induced by each connection is really high (between 10% and 20% per connnection).
I'll try with the leastconnection algo + agent-port every 2 seconds. thanx Sebastien Estienne On Fri, Sep 6, 2013 at 3:10 PM, Willy Tarreau <[email protected]> wrote: > On Thu, Sep 05, 2013 at 12:39:42AM +0200, Sebastien Estienne wrote: > > Hello, > > > > I'm testing the patch of simon implementing agent-port. > > > > I'd like to loadbalance RTMP servers based on the CPU usage, so i > > implemented a small tcp servers that returned the percent of free CPU and > > use the agent-port feature. > > > > I want new connection to always go to the server with the lowest CPU > usage, > > which balancing algorithm should i use to achieve this? > > It does not make sense at all in fact, it means you'd be able to always > check all servers' CPU usage before sending a connection, which would > add a huge overhead and will simply result in all servers appearing > saturated by the measurements. > > In practice, you want to constantly monitor CPU usages (the agent is suited > for this), so that this metric is used to increase or reduce the weight. > Using so, you can use whatever LB algorithm you want. > > The algorithm is simple in the agent : > - if the server is overloaded, reduce the advertised weight > - if the server is underloaded, increase the advertised weight > > This will result in all servers constantly running within the CPU usage > window > you define in your agent, whatever their power and the impact of each of > your > new connections. > > Regards, > Willy > >
