Apache Kafka 1.1.0 发布，改进 Kafka controller

Kafka 1.1.0 包含对了Controller 的重大改进，能加快受控制部分的关闭。Zookeeper回话过期控制就属于此次更新的一部分

控制器改进还允许在 单个集群上支持更多的分区。kip-227引入增量获取请求，当分区的数量大，能提供更有效的应答

KIP-113 added support for replica movement between log directories to enable data balancing with JBOD.

broker 的少量配置操作，比方 SSL keystores ，现在能直接升级，而不使用重启broker，介绍请查看KIP-226

Delegation token based authentication (KIP-48) has been added to Kafka brokers to support large number of clients without overloading Kerberos KDCs or other authentication servers.

Several new features have been added to Kafka Connect, including header support (KIP-145), SSL and Kafka cluster identifiers in the Connect REST interface (KIP-208 and KIP-238), validation of connector names (KIP-212) and support for topic regex in sink connectors (KIP-215). Additionally, the default maximum heap size for Connect workers was increased to 2GB.

Several improvements have been added to the Kafka Streams API, including reducing repartition topic partitions footprint, customizable error handling for produce failures and enhanced resilience to broker unavailability. See KIPs 205, 210, 220, 224 and 239 for details.