Merge latency snapshot

Records phase-level cumulative percentile latency statistics for index merges over time.

Record phase-level cumulative percentile latency statistics for index merges over time.

Note: All statistics reset upon node restart.

This table is configured with gc_grace_seconds 0 to avoid issues with persistent tombstones as rows expire; tombstones are removed during compaction no matter how recently they were created.

JMX analog

com.datastax.bdp/search/core/MergeMetrics

See Merge metrics MBean.

Schema

CREATE TABLE dse_perf.solr_merge_latency_snapshot (
  node_ip inet,
  core text,
  date timestamp,
  time timestamp,
  phase text,
  count bigint,
  latency_percentiles_micros maptext, bigint
  PRIMARY KEY ((node_ip, core, date), phase, time)
)
WITH CLUSTERING ORDER BY (phase ASC, time DESC)
AND gc_grace_seconds=0

Field	Type	Purpose
node_ip	inet	Node IP address.
core	text	Search core name, such as keyspace.table.
date	timestamp	Midnight on the mm/dd/yyyy the snapshot was recorded.
time	timestamp	Time the snapshot was recorded.
phase	text	INIT, WARM, EXECUTE
count	bigint	Cumulative number of queries recorded.
latency_percentiles_micros	map`text`, `bigint`	Cumulative latency percentiles of query: 25%, 50%, 75%, 95%, 99% and 99.9%.

Snapshots recorded on 10/17/2014 for core keyspace.table on the node 127.0.0.1:

SELECT *
FROM solr_merge_latency_snapshot 
WHERE node_ip = '127.0.0.1' AND core = 'keyspace.table' AND date = '2014-10-17';

Most recent 5 snapshots for the EXECUTE phase recorded on 10/17/2014 for core keyspace.table” on the node 127.0.0.1:

SELECT *  
FROM solr_merge_latency_snapshot
WHERE node_ip = '127.0.0.1'
    AND core = 'keyspace.table'
    AND date = '2014-10-17'
    AND phase = 'EXECUTE'
LIMIT 5;