cassandra 的 nodetool 是否只收集单个节点或整个集群的数据？

Question

我有一个 19 节点的 Cassandra 集群用于我们的内部服务。如果我使用 nodetool 登录到一个节点并运行诸如 tablestats 等命令，这是否只为该特定节点或整个集群收集统计信息？

Answer 1

nodetoolcassandra 的实用程序收集整个集群，而不是单个节点。例如，如果您运行如下命令 -

命令：

nodetool tablestats musicdb.artist

结果：

Keyspace: musicdb
Read Count: 0
Read Latency: NaN ms.
Write Count: 0
Write Latency: NaN ms.
Pending Flushes: 0
    Table: artist
    SSTable count: 1
    Space used (live): 62073
    Space used (total): 62073
    Space used by snapshots (total): 0
    Off heap memory used (total): 1400
    SSTable Compression Ratio: 0.27975344141453456
    Number of keys (estimate): 1000
    Memtable cell count: 0
    Memtable data size: 0
    Memtable off heap memory used: 0
    Memtable switch count: 0
    Local read count: 0
    Local read latency: NaN ms
    Local write count: 0
    Local write latency: NaN ms
    Pending flushes: 0
    Bloom filter false positives: 0
    Bloom filter false ratio: 0.00000
    Bloom filter space used: 1264
    Bloom filter off heap memory used: 1256
    Index summary off heap memory used: 128
    Compression metadata off heap memory used: 16
    Compacted partition minimum bytes: 104
    Compacted partition maximum bytes: 149
    Compacted partition mean bytes: 149
    Average live cells per slice (last five minutes): 0.0
    Maximum live cells per slice (last five minutes): 0
    Average tombstones per slice (last five minutes): 0.0
    Maximum tombstones per slice (last five minutes): 0

上面artist属于keyspace的表的状态是来自整个集群。musicdb