Apache Helix 介绍
Helix 是一个通用的集群管理框架，用于自动化的分区、复制和资源分布，提供如下特性：
- Automatic assignment of resource/partition to nodes
- Node failure detection and recovery
- Dynamic addition of Resources
- Dynamic addition of nodes to the cluster
- Pluggable distributed state machine to manage the state of a resource via state transitions
- Automatic load balancing and throttling of transitions
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