Re: Kafka 0.8 without replication - handle broker failure/availability

2013-01-09 Thread Jay Kreps
But I think Maxime's point is valid. In the common case that you don't care about every single message and are willing to tolerate a little loss 0.8 will seem like a pretty big step back. I don't think the solution of just randomly partitioning works because you will still produce 1/nth of your da

Re: Kafka 0.8 without replication - handle broker failure/availability

2013-01-09 Thread Jun Rao
Maxime, First of all, in 0.8, you can choose to have a replication factor of 2. It just means that one can tolerate only one broker failure. Second, our producer logic supports retries on failure. If a message can't be sent, on retry, our default partitioner will select another random partition t

Re: Kafka 0.8 without replication - handle broker failure/availability

2013-01-09 Thread Maxime Brugidou
Thanks for your response. I think the work-around is not really acceptable for me since it will consume 3x the resources (because replication of 3 is the minimum acceptable) and it will still make the cluster less available anyway (unless i have only 3 brokers). The thing is that 0.7 was making th

Re: Kafka 0.8 without replication - handle broker failure/availability

2013-01-09 Thread Jay Kreps
This is a good point. We have discussed this a little bit before. The key constraint is that with replication factor 1 you can choose one of the following: (1) high availability, (2) correct semantic partitioning. That is to say, if a particular partition is unavailable you have no choice but to gi

Kafka 0.8 without replication - handle broker failure/availability

2013-01-09 Thread Maxime Brugidou
Hello, I am currently testing the 0.8 branch (and it works quite well). We plan to not use the replication feature for now since we don't really need it, we can afford to lose data in case of unrecoverable failure from a broker. However, we really don't want to have producers/consumers fail if a b