This seems like a step backwards--we really don't want people to manually manage the location of the controller and try to manually balance partitions off that broker.
I think it might make sense to consider directly fixing the things you actual want to fix: 1. Two many controller moves--we could either just make this cheaper or make the controller location more deterministic e.g. having the election prefer the node with the smallest node id so there were fewer failovers in rolling bounces. 2. You seem to think having the controller on a normal node is a problem. Can you elaborate on what the negative consequences you've observed? Let's focus on fixing those. In general we've worked very hard to avoid having a bunch of dedicated roles for different nodes and I would be very very loath to see us move away from that philosophy. I have a fair amount of experience with both homogenous systems that have a single role and also systems with many differentiated roles and I really think that the differentiated approach causes more problems than it solves for most deployments due to the added complexity. I think we could also fix up this KIP a bit. For example it says there are no public interfaces involved but surely there are new admin commands to control the location? There are also some minor things like listing it as released in 0.8.3 that seem wrong. -Jay On Tue, Oct 20, 2015 at 12:18 PM, Abhishek Nigam < ani...@linkedin.com.invalid> wrote: > Hi, > Can we please discuss this KIP. The background for this is that it allows > us to pin controller to a broker. This is useful in a couple of scenarios: > a) If we want to do a rolling bounce we can reduce the number of controller > moves down to 1. > b) Again pick a designated broker and reduce the number of partitions on it > through admin reassign partitions and designate it as a controller. > c) Dynamically move controller if we see any problems on the broker which > it is running. > > Here is the wiki page > > https://cwiki.apache.org/confluence/display/KAFKA/KIP-39+Pinning+controller+to+broker > > -Abhishek >
