Current state: [ UNDER DISCUSSION ]ACCEPTED
Discussion thread: http://mail-archives.apache.org/mod_mbox/samza-dev/202001.mbox/browser
Released: TBDSamza 1.5
Samza operates in a multi-tenant environment with cluster managers like Yarn and Mesos where a single host can run multiple Samza containers. Often due to soft limits configured for cluster managers like Yarn and no notion of dynamic workload balancing in Samza a host lands in a situation where it is underperforming and it is desired to move one or more containers from that host to other hosts. Today this is not possible without affecting other jobs on the hot host or restarting the affected job manually. In other use cases like resetting checkpoints of a single container or supporting canary or rolling bounces the ability to restart a single or a subset of containers without restarting the whole job is highly desirable.