===================== JMX Metrics Reference

Presto exposes comprehensive metrics via Java Management Extensions (JMX) for monitoring cluster health, query performance, and system behavior. This page documents some important JMX metrics available for production monitoring.

Overview

JMX metrics can be accessed through:

JMX clients: JConsole, VisualVM, or jmxterm
SQL queries: Using the :doc:/connector/jmx connector
Monitoring systems: Prometheus, Grafana, or other JMX exporters

Querying Metrics via SQL

Once configured, you can query metrics using SQL:

.. code-block:: sql

-- List all available metrics
SHOW TABLES FROM jmx.current;

-- Query specific metrics
SELECT * FROM jmx.current."com.facebook.presto.metadata:name=metadatamanagerstats";

Metadata Operation Metrics

JMX Table Name: com.facebook.presto.metadata:name=metadatamanagerstats

Tracks performance and usage of all metadata operations including schema discovery, table lookups, and column information retrieval.

Key Metrics ^^^^^^^^^^^

For each metadata operation such as listSchemaNames, listTables, or getTableHandle:

Call Counters

<operation>Calls: Total number of times the operation was called
Example: listSchemaNamesCalls, listTablesCalls

Timing Statistics

All timing values are in nanoseconds:

<operation>time.alltime.avg: Average execution time across all calls
<operation>time.alltime.min: Fastest execution time
<operation>time.alltime.max: Slowest execution time
<operation>time.alltime.count: Number of samples collected
<operation>time.alltime.p50: Median (50th percentile)
<operation>time.alltime.p75: 75th percentile
<operation>time.alltime.p90: 90th percentile
<operation>time.alltime.p95: 95th percentile
<operation>time.alltime.p99: 99th percentile

Time Windows

Statistics are also available for recent time windows:

<operation>time.oneminute.*: Last 1 minute
<operation>time.fiveminutes.*: Last 5 minutes
<operation>time.fifteenminutes.*: Last 15 minutes

Common Operations ^^^^^^^^^^^^^^^^^

Schema Operations

listSchemaNames: List all schemas in a catalog
getSchemaProperties: Get schema-level properties

Table Operations

listTables: List tables in a schema
getTableHandle: Get table metadata handle
getTableMetadata: Get detailed table information
getTableStatistics: Get table statistics

Column Operations

getColumnHandles: Get column information
getColumnMetadata: Get detailed column metadata

View Operations

listViews: List views in a schema
getView: Get view definition

Example Queries ^^^^^^^^^^^^^^^

Query Lifecycle Metrics

Track query begin and completion times:

.. code-block:: sql

-- Query begin operation metrics
SELECT
    "beginquerytime.alltime.count" as total_queries,
    "beginquerytime.alltime.avg" / 1000.0 as avg_microseconds,
    "beginquerytime.alltime.min" / 1000.0 as min_microseconds,
    "beginquerytime.alltime.max" / 1000.0 as max_microseconds
FROM jmx.current."com.facebook.presto.metadata:name=metadatamanagerstats";

-- Example output:
-- total_queries | avg_microseconds | min_microseconds | max_microseconds
-- 3.0           | 49.42            | 28.63            | 75.38

Insert Operation Metrics

Track data insertion performance:

.. code-block:: sql

-- Begin insert operation metrics
SELECT
    "begininserttime.alltime.count" as insert_operations,
    "begininserttime.alltime.avg" / 1000000000.0 as avg_seconds,
    "begininserttime.alltime.min" / 1000000000.0 as min_seconds,
    "begininserttime.alltime.max" / 1000000000.0 as max_seconds
FROM jmx.current."com.facebook.presto.metadata:name=metadatamanagerstats";

-- Example output:
-- insert_operations | avg_seconds | min_seconds | max_seconds
-- 1.0               | 0.82        | 0.82        | 0.82

-- Finish insert operation metrics
SELECT
    "finishinserttime.alltime.count" as completed_inserts,
    "finishinserttime.alltime.avg" / 1000000000.0 as avg_seconds,
    "finishinserttime.alltime.min" / 1000000000.0 as min_seconds,
    "finishinserttime.alltime.max" / 1000000000.0 as max_seconds
FROM jmx.current."com.facebook.presto.metadata:name=metadatamanagerstats";

-- Example output:
-- completed_inserts | avg_seconds | min_seconds | max_seconds
-- 1.0               | 11.47       | 11.47       | 11.47

System Access Control Metrics

JMX Table Name: com.facebook.presto.security:name=accesscontrolmanager

Tracks performance of access control checks.

Key Metrics ^^^^^^^^^^^

Similar structure to metadata metrics, tracking operations like:

checkCanSetUser: User impersonation checks
checkCanAccessCatalog: Catalog access checks
checkCanSelectFromColumns: Column-level access checks
checkCanCreateTable: Table creation permission checks

Query Execution Metrics

Task Metrics

com.facebook.presto.execution:name=taskmanager: Task execution statistics
com.facebook.presto.execution.executor:name=taskexecutor: Task executor pool metrics

Memory Metrics

com.facebook.presto.memory:name=general,type=memorypool: General memory pool usage
com.facebook.presto.memory:name=reserved,type=memorypool: Reserved memory pool usage

Query Manager Metrics

com.facebook.presto.dispatcher:name=dispatchmanager: Query dispatch statistics
com.facebook.presto.execution:name=querymanager: Query execution statistics

Connector-Specific Metrics

Hive Connector ^^^^^^^^^^^^^^

com.facebook.presto.hive:name=*: Hive metastore and file system metrics

Example -

com.facebook.presto.hive:name=hive,type=cachingdirectorylister

Iceberg Connector ^^^^^^^^^^^^^^^^^

com.facebook.presto.iceberg:name=*: Iceberg-specific caching and I/O metrics

Examples:

com.facebook.presto.iceberg:name=iceberg,type=icebergsplitmanager
com.facebook.presto.iceberg:name=iceberg,type=manifestfilecache
com.facebook.presto.iceberg:name=icebergfilewriterfactory

JMX Metrics Reference

===================== JMX Metrics Reference

Overview

Querying Metrics via SQL

Metadata Operation Metrics

System Access Control Metrics

Query Execution Metrics

Connector-Specific Metrics

See Also