Newts Monitoring

This section describes the metrics OpenNMS HORIZON collects for monitoring the Newts keyspace from org.apache.cassandra.metrics.Keyspace on an Cassandra node.

JMX must be enabled on the Cassandra nodes and made accessible from _OpenNMS HORIZON in order to collect these metrics. See Enabling JMX authentication for details.

The data collection is bound to the agent IP interface with the service name JMX-Cassandra-Newts. The JMXCollector is used to retrieve the MBean entities from the Cassandra node.

All Memory Table Data Size
Name Description

AllMemtablesLiveDataSize

Total amount of live data stored in the memtables (2i and pending flush memtables included) that resides off-heap, excluding any data structure overhead

AllMemtablesOffHeapDataSize

Total amount of data stored in the memtables (2i and pending flush memtables included) that resides off-heap.

AllMemtablesOnHeapDataSize

Total amount of data stored in the memtables (2i and pending flush memtables included) that resides on-heap.

Memtable Switch Count
Name Description

MemtableSwitchCount

Number of times flush has resulted in the memtable being switched out.

Memtable Columns Count
Name Description

MemtableColumnsCount

Total number of columns present in the memtable.

Memory Table Data Size
Name Description

MemtableLiveDataSize

Total amount of live data stored in the memtable, excluding any data structure overhead

MemtableOffHeapDataSize

Total amount of data stored in the memtable that resides off-heap, including column related overhead and partitions overwritten.

MemtableOnHeapDataSize

Total amount of data stored in the memtable that resides on-heap, including column related overhead and partitions overwritten.

Read and Write Latency
Name Description

ReadTotalLatency

Local read metrics.

WriteTotalLatency

Local write metrics.

Range Latency
Name Description

RangeLatency 99th Percentile

Local range slice metrics 99th percentile.

Latency
Name Description

CasCommitTotalLatency

CasPrepareTotalLatency

CasProposeTotalLatency

Bloom Filter Disk Space
Name Description

BloomFilterDiskSpaceUsed

Disk space used by bloom filter

Bloom Filter Off Heap Memory
Name Description

BloomFilterOffHeapMemoryUsed

Off heap memory used by bloom filter

Newts Memory Used
Name Description

 CompressionMetadataOffHeapMemoryUsed

Off heap memory used by compression meta data

IndexSummaryOffHeapMemoryUsed

Off heap memory used by index summary

Pending
Name Description

PendingCompactions

Estimate of number of pending compactions for this column family

PendingFlushes

Estimated number of tasks pending for this column family

Disk Space
Name Description

TotalDiskSpaceUsed

Total disk space used by SSTables belonging to this column family including obsolete ones waiting to be garbage collected.

LiveDiskSpaceUsed

Disk space used by SSTables belonging to this column family