etcd 3.0标志着etcd 3.0的第一个稳定版本的API和数据模型发布，升级很简单，因为同样的etcd2 JSON的端点和内部的集群协议在etcd3仍然提供。尽管如此，但etcd3是基于etcd2用户和实践经验的反馈对API进行大规模的重新设计的。值得关注的更新内容有效率，可靠性和并发控制等一些显著的改进。
更新日志：
Improved latency and throughput
Less protocol overhead via gRPC API layer
Better disk utilization in write ahead log
New storage backend: lower memory overhead per key
Automatic TLS configuration
Some highlights of the new stable etcd3 API:
Flat binary keyspace: no key-value hierarchy / directories
Support key get and watch by prefix
Support key get and watch by interval
Multiversion keyspace: access historical revisions of keys
Transactions: combine multiple requests into one operation
Leases: a single TTL for sets of keys
Maintenance/Alarm: protect etcd from accidental overutilization with storage quotas
Some highlights of new etcdctl:
Mirror: mirror etcd to another data center
Lock: mutex on top of etcd
Elect: leader election
Snapshot: stores point-in-time state of etcd backend
Endpoint: health checking
Experimental Features/APIs:
v3 Auth API
etcd gateway subcommand
下载地址：https://github.com/coreos/etcd/releases/tag/v3.0.0
来自:开源中国社区
