Cassandra JMX 지표

https://cassandra.apache.org/doc/latest/cassandra/operating/metrics.html

Cache Hit Rate

NameTypeDescription

RowCacheHit	Counter	Number of table row cache hits.
KeyCacheHitRate	Gauge	Key cache hit rate for this table.

Memtable & SSTable Size

NameTypeDescription

MemtableOnHeapSize	Gauge	Total amount of data stored in the memtable that resides on-heap, including column related overhead and partitions overwritten.
MemtableOffHeapSize	Gauge	Total amount of data stored in the memtable that resides off-heap, including column related overhead and partitions overwritten.
LiveSSTableCount	Gauge	Number of SSTables on disk for this table.
LiveDiskSpaceUsed	Counter	Disk space used by SSTables belonging to this table (in bytes).
TotalDiskSpaceUsed	Counter	Total disk space used by SSTables belonging to this table, including obsolete ones waiting to be GC’d.

SSTable 접근 빈도

NameTypeDescription

SSTablesPerReadHistogram

Histogram

Histogram of the number of sstable data files accessed per single partition read. SSTables skipped due to Bloom Filters, min-max key or partition index lookup are not taken into acoount

파티션 & 컬럼 카운트 (추정 값)

NameTypeDescription

EstimatedPartitionCount	Gauge	Approximate number of keys in table.
EstimatedColumnCountHistogram	Gauge<long[]>	Histogram of estimated number of columns.

Latency

NameTypeDescription

ReadLatency	Latency	Local read latency for this table.
RangeLatency	Latency	Local range scan latency for this table.
WriteLatency	Latency	Local write latency for this table.
CoordinatorReadLatency	Timer	Coordinator read latency for this table.
CoordinatorWriteLatency	Timer	Coordinator write latency for this table.
CoordinatorScanLatency	Timer	Coordinator range scan latency for this table.

Dropped Mutations

NameTypeDescription

DroppedMutations

Counter

Number of dropped mutations on this table.

Partition Size

NameTypeDescription

MinPartitionSize	Gauge	Size of the smallest compacted partition (in bytes).
MaxPartitionSize	Gauge	Size of the largest compacted partition (in bytes).

Compression

NameTypeDescription

CompressionRatio

Gauge

Current compression ratio for all SSTables.

Bloom Filter

NameTypeDescription

BloomFilterFalsePositives	Gauge	Number of false positives on table’s bloom filter.
BloomFilterFalseRatio	Gauge	False positive ratio of table’s bloom filter.
BloomFilterDiskSpaceUsed	Gauge	Disk space used by bloom filter (in bytes).
BloomFilterOffHeapMemoryUsed	Gauge	Off-heap memory used by bloom filter.