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This document lists the Prometheus metrics provided by the engine application.

These metrics are served by the engine's application monitoring APIs.

Prometheus metrics

Metric Description Type Labels
db_query_duration_seconds Time taken to execute an SQL query Summary, seconds (operation, table, query)
db_stream_duration_seconds Time taken to stream data from an SQL query Summary, seconds (operation, table, query)
listener_messages_total Number of persistent listener messages Counter channel
listener_errors_total Number of persistent listener errors Counter
migration_cache_misses_total Number of migration DB cache misses in the NPL migration Counter
migration_cache_fetches_total Number of migration DB cache fetches (hits & misses) in the NPL migration Counter
migration_noop_states_total Number of protocols that were not transformed in the NPL migration Counter
migration_step_duration_seconds Time taken to process an NPL migration step Summary, seconds step
streams_concurrent_consumers_count Number of concurrent stream consumers Gauge stream
deprecations_usages_count Number of deprecated NPL feature usages Gauge
deprecations_transformation_duration_seconds Time taken to analyse deprecation analyser's scheduled call Summary, seconds
scheduler_run_duration_seconds Time taken to run a scheduler task Summary, seconds
api_request_duration_seconds Time taken for the API request calls Summary, seconds (interface, operation, url)
multinode_request_duration_seconds Time taken for the multinode request calls to other nodes Summary, seconds node_addr
jwt_validation_duration_seconds Time taken for the JWT validation Summary, seconds
jwt_validation_errors_total Number of JWT validation errors Counter type
cache_evictions_total Number of cache evictions Counter cache
amqp_publish_duration_seconds Time taken to publish an AMQP message Summary, seconds
amqp_publish_errors_total Number of AMQP message publishing errors Counter
amqp_batch_size_count Size of most recent AMQP message batch Gauge
amqp_poll_errors_total Number of AMQP polling errors Counter

Additionally, we expose HikariCP metrics.