Cassandra：讀/寫/ s

Question

我試圖弄清楚我的Cassandra集羣的吞吐量，並且無法弄清楚如何使用nodetool來完成該操作。下面是一個示例輸出：

Starting NodeTool 
Keyspace: realtimetrader 
Read Count: 0 
Read Latency: NaN ms. 
Write Count: 402 
Write Latency: 0.09648756218905473 ms. 
Pending Flushes: 0 
     Table: currencies 
     SSTable count: 1 
     Space used (live): 5254 
     Space used (total): 5254 
     Space used by snapshots (total): 0 
     Off heap memory used (total): 40 
     SSTable Compression Ratio: 0.0 
     Number of keys (estimate): 14 
     Memtable cell count: 1608 
     Memtable data size: 567 
     Memtable off heap memory used: 0 
     Memtable switch count: 0 
     Local read count: 0 
     Local read latency: NaN ms 
     Local write count: 402 
     Local write latency: 0.106 ms 
     Pending flushes: 0 
     Bloom filter false positives: 0 
     Bloom filter false ratio: 0,00000 
     Bloom filter space used: 24 
     Bloom filter off heap memory used: 16 
     Index summary off heap memory used: 16 
     Compression metadata off heap memory used: 8 
     Compacted partition minimum bytes: 125 
     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 

我運行命令：

nodetool cfstats 

得到這個，然後減去後者，「本地讀取計數：」從較早的企業之一。 但我不確定這裏的「本地」是什麼意思？ 這是否意味着它的本地到該節點，並在一個5節點環，我應該多個值5？還是說簡單的減法會給我正確的結果？

此外，我應該看哪個JMX bean來獲取這些＃的？

Answer 1

看看這個nodetool cfstats。

我認爲你要找的是'讀取延遲'和'寫入延遲'。 這些字段表示讀取/寫入在羣集中的速度。