我非常需要ColumnFamily中的行数,但cassandra 2.1.2中的“nodetool cfstats”输出中缺少“键数”.现在如何计算行数？
这是cfstats的输出
Keyspace: liftrmt
Read Count: 0
Read Latency: NaN ms.
Write Count: 0
Write Latency: NaN ms.
Pending Flushes: 0
Table: reportcodedaycount
SSTable count: 4
Space used (live): 11.49 MB
Space used (total): 11.49 MB
Space used by snapshots (total): 0 bytes
SSTable Compression Ratio: 0.38099920748493266
Memtable cell count: 0
Memtable data size: 0 bytes
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: 64 bytes
Compacted partition minimum bytes: 444.17 KB
Compacted partition maximum bytes: 6.68 MB
Compacted partition mean bytes: 4.17 MB
Average live cells per slice (last five minutes): 0.0
Maximum live cells per slice (last five minutes): 0.0
Average tombstones per slice (last five minutes): 0.0
Maximum tombstones per slice (last five minutes): 0.0
解决方法
您需要使用可通过JMX访问的新指标.我将使用JConsole访问它们.
打开jconsole然后导航到：
org.apache.cassandra.metrics
-> ColumnFamily
-> ksname (in my case test)
-> cfname (in my case group)
-> EstimatedColumnCountHistogram
-> Attributes -> Value
打开long [90]数组,在我的例子中它是第二个值.这些是sstables中的键,如果它在memtable中,它不能通过这个度量访问(即如果你想看到它,你需要将你的memtables刷新到sstables).
为了清楚起见,下面插入test.group的22个唯一键的屏幕截图…
更多关于new metrics API.