See List of metrics for all metrics per release.
Note that any etcd_debugging_* metrics are experimental and subject to change.
- Add etcd_cluster_version Prometheus metric.
- Add etcd_debugging_mvcc_total_put_size_in_bytes Prometheus metric.
Previously, during shutdown etcd could accidentally remove needed wal files, resulting in catastrophic error 「etcdserver: open wal error: wal: file not found.」 during startup. Now, etcd makes sure the purge file loop exits before server signals stop of the raft node.