Re: Kafka cluster with lots of topics

2013-11-18 Thread Robert Rodgers
If I understand your comment correctly you are trying to use kafka topics as per-endpoint message queues. I may be mistaken, but to me Kafka seems does not really seem like a good match for that. For such a purpose you will eventually want something that is not actually a queue - a means to

Re: Kafka cluster with lots of topics

2013-11-14 Thread Joe Freeman
Thanks for the replies. I don't think Kafka quite fits our use case, unfortunately. To abstractly answer Edward's question: in a system with lots of users, we were considering having a topic per user (such that an individual user can connect from a number of endpoints and receive events, including

Re: Kafka cluster with lots of topics

2013-11-13 Thread Edward Capriolo
Zookeeper will not be the only problem. The first is that each topic is a directory on the file system. Each of those is going to have files inside it. This is going to be fairly overwhelming for the file system. Also I can not speak for the internals but there may be cases where this many topics a

Re: Kafka cluster with lots of topics

2013-11-13 Thread Neha Narkhede
A node being added will generally not lead to any leader election. A node being removed will lead to leader election. You can force leader election using the preferred replica election command - https://cwiki.apache.org/confluence/display/KAFKA/Replication+tools#Replicationtools-2.PreferredReplicaL

Re: Kafka cluster with lots of topics

2013-11-13 Thread hsy...@gmail.com
I didn't see any auto leader election for adding nodes. The data are still skewed on the old nodes. You have to force it by running script? On Wed, Nov 13, 2013 at 6:41 AM, Neha Narkhede wrote: > At those many topics, zookeeper will be the main bottleneck. Leader > election process will take ver

Re: Kafka cluster with lots of topics

2013-11-13 Thread Neha Narkhede
At those many topics, zookeeper will be the main bottleneck. Leader election process will take very long increasing the unavailability window of the cluster. Thanks, Neha On Nov 13, 2013 4:49 AM, "Joe Freeman" wrote: > Would I be correct in assuming that a Kafka cluster won't scale well to > sup