rmdmattingly opened a new pull request, #6543: URL: https://github.com/apache/hbase/pull/6543
See my design doc [here](https://docs.google.com/document/d/1jA8Ghs86v7b-53j5DcsdbPnOXxbHjewkIBFi1E4S1pY/edit?usp=sharing) To sum it up, the current load balancer isn't great for what it's supposed to do now, and it won't support all of the things that we'd like it to do in a perfect world. Right now: primary replica balancing squashes all other considerations. The default weight for one of the several cost functions that factor into primary replica balancing is 100,000. Meanwhile the default read request cost is 5. The result is that the load balancer, OOTB, basically doesn't care about balancing actual load. To solve this, you can either set primary replica balancing costs to zero, which is fine if you don't use read replicas, or — if you do use read replicas — maybe you can produce a magic incantation of configurations that work _just_ right, until your needs change. In the future: we'd like a lot more out of the balancer. System table isolation, meta table isolation, colocation of regions based on start key prefix similarity (this is a very rough idea atm, and not touched in the scope of this PR). And to support all of these features with either cost functions or RS groups would be a real burden. I think what I'm proposing here will be a much, much easier path for HBase operators. cc @ndimiduk @charlesconnell @ksravista @aalhour -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
