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MariaDB

Plugin: go.d.plugin Module: mysql

Overview

This collector monitors the health and performance of MySQL servers and collects general statistics, replication and user metrics.

It connects to the MySQL instance via a TCP or UNIX socket and executes the following commands:

Executed queries:

SELECT VERSION();
SHOW GLOBAL STATUS;
SHOW ENGINE INNODB STATUS;
SHOW GLOBAL VARIABLES;
SHOW SLAVE STATUS; or SHOW ALL SLAVES STATUS; (MariaDBv10.2+) or SHOW REPLICA STATUS; (MySQL 8.0.22+)
SHOW USER_STATISTICS; (MariaDBv10.1.1+)
SELECT TIME,USER FROM INFORMATION_SCHEMA.PROCESSLIST;

This collector is supported on all platforms.

This collector supports collecting metrics from multiple instances of this integration, including remote instances.

MariaDB can be monitored further using the following other integrations:

Default Behavior

Auto-Detection

By default, it detects instances running on localhost by trying to connect as root and netdata using known MySQL TCP sockets:

127.0.0.1:3306
"[::1]:3306"

Limits

The default configuration for this integration does not impose any limits on data collection.

Performance Impact

The default configuration for this integration is not expected to impose a significant performance impact on the system.

Setup

You can configure the mysql collector in two ways:

Method	Best for	How to
UI	Fast setup without editing files	Go to Nodes → Configure this node → Collectors → Jobs, search for mysql, then click + to add a job.
File	If you prefer configuring via file, or need to automate deployments (e.g., with Ansible)	Edit `go.d/mysql.conf` and add a job.

:::important

UI configuration requires paid Netdata Cloud plan.

:::

Prerequisites

Create netdata user

A user account should have the following permissions:

To create the netdata user with these permissions, execute the following in the MySQL shell:

MySQL and MariaDB < 10.5.9

  CREATE USER 'netdata'@'localhost';
  GRANT USAGE, REPLICATION CLIENT, PROCESS ON *.* TO 'netdata'@'localhost';
  FLUSH PRIVILEGES;

MariaDB >= 10.5.9

For MariaDB 10.5.9 and later, use the SLAVE MONITOR privilege instead of REPLICATION CLIENT:

  CREATE USER 'netdata'@'localhost';
  GRANT USAGE, SLAVE MONITOR, PROCESS ON *.* TO 'netdata'@'localhost';
  FLUSH PRIVILEGES;

The netdata user will have the ability to connect to the MySQL server on localhost without a password. It will only be able to gather statistics without being able to alter or affect operations in any way.

Enable User Statistics (optional)

To collect per-user statistics, the User Statistics plugin must be enabled. This is available for MariaDB and Percona, not for MySQL.

By default, statistics are not collected. To enable the plugin, set the userstat system variable.

In a configuration file (persistent, requires restart):

  [mariadb]
  userstat = 1

Dynamically (takes effect immediately, does not persist across restarts):

  SET GLOBAL userstat=1;

Configuration

Options

The following options can be defined globally: update_every, autodetection_retry.

Config options

| Group | Option | Description | Default | Required | |:------|:-----|:------------|:--------|:---------:| | **Collection** | update_every | Data collection interval (seconds). | 5 | no | | | autodetection_retry | Autodetection retry interval (seconds). Set 0 to disable. | 0 | no | | **Target** | dsn | MySQL server DSN (Data Source Name). See [DSN syntax](https://github.com/go-sql-driver/mysql#dsn-data-source-name). | root@tcp(localhost:3306)/ | yes | | | my.cnf | Path to a `my.cnf` file to read connection settings from the `[client]` section. | | no | | | timeout | Query timeout (seconds). | 1 | no | | **Functions** | functions.top_queries.disabled | Disable the [top-queries](#top-queries) function. | no | no | | | functions.top_queries.timeout | Query timeout (seconds). Uses collector timeout if not set. | | no | | | functions.top_queries.limit | Maximum number of queries to return. | 500 | no | | | functions.deadlock_info.disabled | Disable the [deadlock-info](#deadlock-info) function. | no | no | | | functions.deadlock_info.timeout | Query timeout (seconds). Uses collector timeout if not set. | | no | | | functions.error_info.disabled | Disable the [error-info](#error-info) function. | no | no | | | functions.error_info.timeout | Query timeout (seconds). Uses collector timeout if not set. | | no | | **Virtual Node** | vnode | Associates this data collection job with a [Virtual Node](https://learn.netdata.cloud/docs/netdata-agent/configuration/organize-systems-metrics-and-alerts#virtual-nodes). | | no |

via UI

Configure the mysql collector from the Netdata web interface:

Go to Nodes.
Select the node where you want the mysql data-collection job to run and click the :gear: (Configure this node). That node will run the data collection.
The Collectors → Jobs view opens by default.
In the Search box, type mysql (or scroll the list) to locate the mysql collector.
Click the + next to the mysql collector to add a new job.
Fill in the job fields, then click Test to verify the configuration and Submit to save.
- Test runs the job with the provided settings and shows whether data can be collected.
- If it fails, an error message appears with details (for example, connection refused, timeout, or command execution errors), so you can adjust and retest.

via File

The configuration file name for this integration is go.d/mysql.conf.

The file format is YAML. Generally, the structure is:

update_every: 1
autodetection_retry: 0
jobs:
  - name: some_name1
  - name: some_name2

You can edit the configuration file using the edit-config script from the Netdata config directory.

cd /etc/netdata 2>/dev/null || cd /opt/netdata/etc/netdata
sudo ./edit-config go.d/mysql.conf

Examples

TCP socket

An example configuration.

Config

```yaml jobs: - name: local dsn: netdata@tcp(127.0.0.1:3306)/ ```

Unix socket

An example configuration.

Config

```yaml jobs: - name: local dsn: netdata@unix(/var/lib/mysql/mysql.sock)/ ```

Connection with password

An example configuration.

Config

```yaml jobs: - name: local dsn: netconfig:password@tcp(127.0.0.1:3306)/ ```

my.cnf

An example configuration.

Config

```yaml jobs: - name: local my.cnf: '/etc/my.cnf' ```

Multi-instance

Note: When you define multiple jobs, their names must be unique.

Local and remote instances.

Config

```yaml jobs: - name: local dsn: netdata@tcp(127.0.0.1:3306)/ - name: remote dsn: netconfig:password@tcp(203.0.113.0:3306)/ ```

Alerts

The following alerts are available:

Alert name	On metric	Description
mysql_10s_slow_queries	mysql.queries	number of slow queries in the last 10 seconds
mysql_10s_table_locks_immediate	mysql.table_locks	number of table immediate locks in the last 10 seconds
mysql_10s_table_locks_waited	mysql.table_locks	number of table waited locks in the last 10 seconds
mysql_10s_waited_locks_ratio	mysql.table_locks	ratio of waited table locks over the last 10 seconds
mysql_connections	mysql.connections_active	client connections utilization
mysql_replication	mysql.slave_status	replication status (0: stopped, 1: working)
mysql_replication_lag	mysql.slave_behind	difference between the timestamp of the latest transaction processed by the SQL thread and the timestamp of the same transaction when it was processed on the master
mysql_galera_cluster_size_max_2m	mysql.galera_cluster_size	maximum galera cluster size in the last 2 minutes starting one minute ago
mysql_galera_cluster_size	mysql.galera_cluster_size	current galera cluster size, compared to the maximum size in the last 2 minutes
mysql_galera_cluster_state_warn	mysql.galera_cluster_state	galera node state is either Donor/Desynced or Joined
mysql_galera_cluster_state_crit	mysql.galera_cluster_state	galera node state is either Undefined or Joining or Error
mysql_galera_cluster_status	mysql.galera_cluster_status	galera node is part of a nonoperational component. This occurs in cases of multiple membership changes that result in a loss of Quorum or in cases of split-brain situations.

Metrics

Metrics grouped by scope.

The scope defines the instance that the metric belongs to. An instance is uniquely identified by a set of labels.

Per MariaDB instance

These metrics refer to the entire monitored application.

This scope has no labels.

Metrics:

Metric	Dimensions	Unit	MySQL	MariaDB	Percona
mysql.net	in, out	kilobits/s	•	•	•
mysql.queries	queries, questions, slow_queries	queries/s	•	•	•
mysql.queries_type	select, delete, update, insert, replace	queries/s	•	•	•
mysql.handlers	commit, delete, prepare, read_first, read_key, read_next, read_prev, read_rnd, read_rnd_next, rollback, savepoint, savepointrollback, update, write	handlers/s	•	•	•
mysql.table_open_cache_overflows	open_cache	overflows/s	•	•	•
mysql.table_locks	immediate, waited	locks/s	•	•	•
mysql.join_issues	full_join, full_range_join, range, range_check, scan	joins/s	•	•	•
mysql.sort_issues	merge_passes, range, scan	issues/s	•	•	•
mysql.tmp	disk_tables, files, tables	events/s	•	•	•
mysql.connections	all, aborted	connections/s	•	•	•
mysql.connections_active	active, limit, max_active	connections	•	•	•
mysql.threads	connected, cached, running	threads	•	•	•
mysql.threads_created	created	threads/s	•	•	•
mysql.thread_cache_misses	misses	misses	•	•	•
mysql.innodb_io	read, write	KiB/s	•	•	•
mysql.innodb_io_ops	reads, writes, fsyncs	operations/s	•	•	•
mysql.innodb_io_pending_ops	reads, writes, fsyncs	operations	•	•	•
mysql.innodb_log	waits, write_requests, writes	operations/s	•	•	•
mysql.innodb_redo_log_activity	redo_written, checkpointed	B/s	•	•	•
mysql.innodb_redo_log_occupancy	occupancy	percentage	•	•	•
mysql.innodb_redo_log_checkpoint_age	age	B	•	•	•
mysql.innodb_cur_row_lock	current waits	operations	•	•	•
mysql.innodb_rows	inserted, read, updated, deleted	operations/s	•	•	•
mysql.innodb_buffer_pool_pages	data, dirty, free, misc, total	pages	•	•	•
mysql.innodb_buffer_pool_pages_flushed	flush_pages	requests/s	•	•	•
mysql.innodb_buffer_pool_bytes	data, dirty	MiB	•	•	•
mysql.innodb_buffer_pool_read_ahead	all, evicted	pages/s	•	•	•
mysql.innodb_buffer_pool_read_ahead_rnd	read-ahead	operations/s	•	•	•
mysql.innodb_buffer_pool_ops	disk_reads, wait_free	operations/s	•	•	•
mysql.innodb_os_log	fsyncs, writes	operations	•	•	•
mysql.innodb_os_log_fsync_writes	fsyncs	operations/s	•	•	•
mysql.innodb_os_log_io	write	KiB/s	•	•	•
mysql.innodb_deadlocks	deadlocks	operations/s	•	•	•
mysql.files	files	files	•	•	•
mysql.files_rate	files	files/s	•	•	•
mysql.connection_errors	accept, internal, max, peer_addr, select, tcpwrap	errors/s	•	•	•
mysql.opened_tables	tables	tables/s	•	•	•
mysql.open_tables	cache, tables	tables	•	•	•
mysql.process_list_fetch_query_duration	duration	milliseconds	•	•	•
mysql.process_list_queries_count	system, user	queries	•	•	•
mysql.process_list_longest_query_duration	duration	seconds	•	•	•
mysql.qcache_ops	hits, lowmem_prunes, inserts, not_cached	queries/s	•	•	•
mysql.qcache	queries	queries	•	•	•
mysql.qcache_freemem	free	MiB	•	•	•
mysql.qcache_memblocks	free, total	blocks	•	•	•
mysql.galera_writesets	rx, tx	writesets/s	•	•	•
mysql.galera_bytes	rx, tx	KiB/s	•	•	•
mysql.galera_queue	rx, tx	writesets	•	•	•
mysql.galera_conflicts	bf_aborts, cert_fails	transactions	•	•	•
mysql.galera_flow_control	paused	ms	•	•	•
mysql.galera_cluster_status	primary, non_primary, disconnected	status	•	•	•
mysql.galera_cluster_state	undefined, joining, donor, joined, synced, error	state	•	•	•
mysql.galera_cluster_size	nodes	nodes	•	•	•
mysql.galera_cluster_weight	weight	weight	•	•	•
mysql.galera_connected	connected	boolean	•	•	•
mysql.galera_ready	ready	boolean	•	•	•
mysql.galera_open_transactions	open	transactions	•	•	•
mysql.galera_thread_count	threads	threads	•	•	•
mysql.key_blocks	unused, used, not_flushed	blocks	•	•	•
mysql.key_requests	reads, writes	requests/s	•	•	•
mysql.key_disk_ops	reads, writes	operations/s	•	•	•
mysql.binlog_cache	disk, all	transactions/s	•	•	•
mysql.binlog_stmt_cache	disk, all	statements/s	•	•	•

Per connection

These metrics refer to the replication connection.

This scope has no labels.

Metrics:

Metric	Dimensions	Unit	MySQL	MariaDB	Percona
mysql.slave_behind	seconds	seconds	•	•	•
mysql.slave_status	sql_running, io_running	boolean	•	•	•

Per user

These metrics refer to the MySQL user.

Labels:

Label	Description
user	username

Metrics:

Metric	Dimensions	Unit	MariaDB	Percona
mysql.userstats_cpu	used	percentage	•	•
mysql.userstats_rows	read, sent, updated, inserted, deleted	operations/s	•	•
mysql.userstats_commands	select, update, other	commands/s	•	•
mysql.userstats_denied_commands	denied	commands/s	•	•
mysql.userstats_created_transactions	commit, rollback	transactions/s	•	•
mysql.userstats_binlog_written	written	B/s	•	•
mysql.userstats_empty_queries	empty	queries/s	•	•
mysql.userstats_connections	created	connections/s	•	•
mysql.userstats_lost_connections	lost	connections/s	•	•
mysql.userstats_denied_connections	denied	connections/s	•	•

Live Data

This collector exposes real-time functions for interactive troubleshooting in the Live tab.

Top Queries

Retrieves aggregated SQL query performance metrics from MySQL performance_schema.events_statements_summary_by_digest table.

This function queries the events_statements_summary_by_digest table which contains aggregated statistics for SQL statements grouped by their digest (normalized query pattern). The function dynamically detects available columns based on your MySQL/MariaDB version.

Use cases: - Identify slow queries that consume the most execution time - Find frequently executed queries that may benefit from optimization - Detect queries with high lock time, errors, or table scans

Query text is truncated at 4096 characters for display purposes.

Aspect	Description
Name	`Mysql:top-queries`
Require Cloud	yes
Performance	Queries the `events_statements_summary_by_digest` table: • On busy servers with high query throughput, the digest table can grow large • Default limit of 500 rows balances usefulness with performance
Security	Query text may contain unmasked literal values including potentially sensitive data: • Personal information in WHERE clauses or INSERT values • Business data and internal identifiers • Access should be restricted to authorized personnel only
Availability	Available when: • The collector has successfully connected to MySQL • Performance Schema is enabled with statement digest collection • Returns HTTP 503 if collector is still initializing • Returns HTTP 500 if the query fails • Returns HTTP 504 if the query times out

Prerequisites

Enable performance_schema statement digest collection

Performance Schema must be enabled and statement instrumentation must be configured to collect digest statistics.

Check if Performance Schema is enabled: sql SELECT @@performance_schema;
Check statement instrumentation configuration: sql SELECT * FROM performance_schema.setup_consumers WHERE NAME LIKE '%statement%';
The following consumer should be enabled:
- events_statements_summary_by_digest
Enable statement consumers if needed: sql UPDATE performance_schema.setup_consumers SET ENABLED = 'YES' WHERE NAME LIKE 'events_statements%';

:::info

Changes to setup_consumers take effect immediately without requiring a server restart.
MariaDB also supports the events_statements_summary_by_digest table. Exact consumer names may vary by MariaDB version, so checking setup_consumers first as shown above is recommended.

:::

Verify digest table contains data: sql SELECT COUNT(*) FROM performance_schema.events_statements_summary_by_digest;

Note: Statement digest data is accumulated since server startup or since the table was last truncated. To reset statistics: sql TRUNCATE TABLE performance_schema.events_statements_summary_by_digest;

Ensure that statement instruments are enabled in the Performance Schema so that statement digest statistics are collected. Refer to your MySQL or MariaDB version documentation for the appropriate configuration options.

Grant SELECT permission on Performance Schema tables

The netdata user must have SELECT permission on Performance Schema tables. The standard collector permissions (USAGE, REPLICATION CLIENT, PROCESS) do not automatically include Performance Schema access.

Grant the required permission: sql GRANT SELECT ON performance_schema.* TO 'netdata'@'localhost'; FLUSH PRIVILEGES;

:::info

The host part ('localhost') should match how the netdata user connects. If connecting via TCP/IP, you may need 'netdata'@'%' or a specific IP address instead.

:::

Verify access: sql -- As the netdata user: SELECT COUNT(*) FROM performance_schema.events_statements_summary_by_digest;

Parameters

Parameter	Type	Description	Required	Default	Options
Filter By	select	Select the primary sort column. The available options depend on your MySQL/MariaDB version and include metrics like total execution time, number of calls, lock time, errors, rows examined, and more. Defaults to total execution time.	yes	totalTime

Returns

Aggregated statement statistics from Performance Schema, grouped by query digest. Each row represents a unique query pattern with cumulative metrics across all executions.

Column	Type	Unit	Visibility	Description
Digest	string		hidden	Unique hash identifier for the normalized query pattern. Queries with the same structure (different literal values) share the same digest.
Query	string			Normalized SQL query text with literals replaced by placeholders (e.g., '?' for values). Truncated to 4096 characters.
Schema	string			Database schema name where the query was executed. Empty string for queries without a schema context.
Calls	integer			Total number of times this query pattern has been executed since server startup or since the digest table was last truncated.
Total Time	duration	milliseconds		Cumulative execution time across all executions. High values indicate queries that consume significant server resources.
Min Time	duration	milliseconds	hidden	Minimum execution time observed for a single execution. Helps identify variability in query performance.
Avg Time	duration	milliseconds		Average execution time (total time divided by calls). Use this to compare performance across different query patterns.
Max Time	duration	milliseconds	hidden	Maximum execution time observed for a single execution. Large gaps between min and max may indicate performance instability.
Lock Time	duration	milliseconds		Total time spent waiting for table locks across all executions. High lock time may indicate contention from concurrent transactions.
Errors	integer			Total number of times this query pattern resulted in an error. Non-zero values require investigation into the underlying issue.
Warnings	integer			Total number of times this query pattern generated warnings. Warnings may indicate data type conversions, NULL handling issues, or other non-critical problems.
Error Attribution	string			Status of error detail attribution for this query. Values: enabled (error details available), no_data (no recent error for this digest), not_enabled (statement history consumers disabled), not_supported (required columns unavailable).
Error Number	integer			Most recent error number observed for this query digest (when error attribution is enabled).
SQL State	string		hidden	SQLSTATE code for the most recent error (when error attribution is enabled).
Error Message	string			Most recent error message for this query digest (when error attribution is enabled).
Rows Affected	integer			Total number of rows modified by INSERT, UPDATE, DELETE, or REPLACE statements. Useful for tracking write workloads.
Rows Sent	integer			Total number of rows returned to the client by SELECT statements. High values may indicate result sets that are too large.
Rows Examined	integer			Total number of rows read during query execution. A high ratio of rows examined to rows sent suggests missing or inefficient indexes.
Temp Disk Tables	integer			Total number of temporary tables created on disk across all executions. Disk-based temporary tables are significantly slower than in-memory tables and may indicate memory pressure or complex operations requiring sorting/grouping.
Temp Tables	integer			Total number of temporary tables created (both in-memory and on-disk). High values suggest frequent sorting, grouping, or DISTINCT operations.
Full Joins	integer			Total number of joins that performed a full table scan without using an index. These are typically very expensive operations that should be optimized.
Full Range Joins	integer		hidden	Total number of joins that used a range scan on the first table. Less efficient than indexed joins but better than full scans.
Select Range	integer		hidden	Total number of joins that used a range on the first table for row selection.
Select Range Check	integer		hidden	Total number of joins that checked each row after scanning for key ranges. Very inefficient operation.
Select Scan	integer			Total number of joins that performed a full scan of the first table. Indicates missing indexes or suboptimal join order.
Sort Merge Passes	integer		hidden	Total number of merge passes performed during sort operations. More passes indicate larger datasets that exceed sort buffer size.
Sort Range	integer		hidden	Total number of sorts that used a range scan.
Sort Rows	integer			Total number of rows sorted across all executions. High values indicate frequent sorting operations on large datasets.
Sort Scan	integer		hidden	Total number of sorts that required a full table scan.
No Index Used	integer			Total number of executions where no index was used for table access. These queries are prime candidates for index optimization.
No Good Index Used	integer		hidden	Total number of executions where a non-optimal index was used. Indicates that while an index exists, a better one might improve performance.
First Seen	string		hidden	Timestamp when this query pattern was first observed. Helps identify new queries that may have been introduced by application changes.
Last Seen	string		hidden	Timestamp when this query pattern was last executed. Can help identify stale queries that are no longer in use.
P95 Time	duration	milliseconds		95th percentile execution time. 95% of executions completed within this time. Available in MySQL 8.0+. Useful for understanding typical performance.
P99 Time	duration	milliseconds		99th percentile execution time. 99% of executions completed within this time. Available in MySQL 8.0+. Helps identify outlier slow executions.
P99.9 Time	duration	milliseconds	hidden	99.9th percentile execution time. Available in MySQL 8.0+. Identifies extreme outliers in query performance.
Sample Query	string		hidden	Example of an actual query execution with literal values preserved. Available in MySQL 8.0+. Helpful for understanding the exact queries being executed.
Sample Seen	string		hidden	Timestamp when the sample query was captured. Available in MySQL 8.0+.
Sample Time	duration	milliseconds	hidden	Execution time of the captured sample query. Available in MySQL 8.0+.
CPU Time	duration	milliseconds		Total CPU time consumed across all executions. Available in MySQL 8.0.28+. Helps identify CPU-intensive queries.
Max Controlled Memory	integer			Maximum memory controlled by the query executor for this query pattern. Available in MySQL 8.0.31+. Helps identify memory-intensive operations.
Max Total Memory	integer			Maximum total memory used by this query pattern including both controlled and uncontrolled allocations. Available in MySQL 8.0.31+.

Deadlock Info

Retrieves the latest detected InnoDB deadlock from SHOW ENGINE INNODB STATUS.

The output is parsed to attribute the deadlock to the participating transactions and their query text, lock mode, lock status, and wait resource.

Use cases: - Identify which query was chosen as the deadlock victim - Inspect the waiting lock resource and lock mode - Correlate deadlocks with application changes or deployment events

Query text is truncated at 4096 characters for display purposes.

Aspect	Description
Name	`Mysql:deadlock-info`
Require Cloud	yes
Performance	Executes `SHOW ENGINE INNODB STATUS` on demand: • Not part of regular collection • Query cost depends on server load and the size of the InnoDB status output
Security	Query text and wait resource strings may include unmasked literal values including sensitive data (PII/secrets): • SQL literals such as emails, IDs, or tokens • Schema and table names that may be sensitive in some environments • Restrict dashboard access to authorized personnel only
Availability	Available when: • The collector has successfully connected to MySQL • `deadlock_info_function_enabled` is true • The account can run `SHOW ENGINE INNODB STATUS` (PROCESS privilege) • Returns HTTP 200 with empty data when no deadlock is found • Returns HTTP 403 when PROCESS privilege is missing • Returns HTTP 500 if the query fails • Returns HTTP 504 if the query times out • Returns HTTP 561 when the deadlock section cannot be parsed • Returns HTTP 503 if the collector is still initializing or the function is disabled

Prerequisites

Enable deadlock-info function in Netdata

Set deadlock_info_function_enabled: true in the go.d/mysql.conf job.

Grant PROCESS privilege

The monitoring user must have PROCESS privilege to run SHOW ENGINE INNODB STATUS.

Parameters

This function has no parameters.

Returns

Parsed deadlock participants from the latest detected deadlock. Each row represents one transaction involved in the deadlock.

Column	Type	Visibility	Description
Row ID	string	hidden	Unique row identifier composed of deadlock ID and process ID.
Deadlock ID	string		Identifier for the deadlock event, used to group participating transactions.
Timestamp	timestamp		Timestamp of the deadlock event. Parsed from the deadlock section when available; otherwise the function execution time.
Process ID	string		MySQL thread id of the transaction involved in the deadlock.
Connection ID	integer		Numeric connection identifier when the process id is numeric.
ECID	integer		Execution context id (engine-specific). This is typically null for MySQL and reserved for cross-engine consistency.
Victim	string		"true" when the transaction was chosen as the deadlock victim and rolled back; otherwise "false".
Query	string		SQL query text for the transaction involved in the deadlock. Truncated to 4096 characters.
Lock Mode	string		Lock mode reported for the waiting lock (for example X or S).
Lock Status	string		Lock status for the transaction. WAITING indicates the transaction was waiting on a lock.
Wait Resource	string		Lock resource line from InnoDB status showing what the transaction was waiting on.
Database	string		Database name when it can be inferred. This may be empty or null depending on the deadlock output.

Error Info

Retrieves recent SQL errors from Performance Schema statement history tables.

This function reads performance_schema.events_statements_history_long when enabled, otherwise falls back to performance_schema.events_statements_history. It reports the most recent error per query digest, including error number, SQLSTATE, and message.

Use cases: - Identify recent query errors and their messages - Correlate errors to query patterns (digest) - Validate error rates seen in top-queries

Error messages are truncated by Performance Schema (usually 128 characters).

Aspect	Description
Name	`Mysql:error-info`
Require Cloud	yes
Performance	Reads Performance Schema statement history tables on demand: • Not part of regular collection • Query cost depends on history table size and server load
Security	Error messages and query text may include unmasked literals (PII/secrets). • Restrict dashboard access to authorized personnel only
Availability	Available when: • The collector has successfully connected to MySQL • `error_info_function_enabled` is true • Performance Schema statement history consumers are enabled (history and/or history_long) • Returns HTTP 200 with empty data when no errors are found • Returns HTTP 503 when required consumers are not enabled or function disabled • Returns HTTP 500 if the query fails • Returns HTTP 504 if the query times out

Prerequisites

Enable error-info function in Netdata

Set error_info_function_enabled: true in the go.d/mysql.conf job.

Enable statement history consumers

Ensure events_statements_history and/or events_statements_history_long consumers are enabled.

Grant SELECT on Performance Schema

The monitoring user must have SELECT on performance_schema.* to read statement history tables.

Parameters

This function has no parameters.

Returns

Most recent error per query digest from Performance Schema history tables.

Column	Type	Visibility	Description
Digest	string	hidden	Unique hash identifier for the normalized query pattern.
Query	string		Normalized query text when available (digest text or SQL text).
Schema	string		Database schema name when available.
Error Number	integer		MySQL error number for the most recent error of this digest.
SQL State	string		SQLSTATE code for the most recent error.
Error Message	string		Error message for the most recent error.

Troubleshooting

Debug Mode

Important: Debug mode is not supported for data collection jobs created via the UI using the Dyncfg feature.

To troubleshoot issues with the mysql collector, run the go.d.plugin with the debug option enabled. The output should give you clues as to why the collector isn't working.

Navigate to the plugins.d directory, usually at /usr/libexec/netdata/plugins.d/. If that's not the case on your system, open netdata.conf and look for the plugins setting under [directories].

  cd /usr/libexec/netdata/plugins.d/

Switch to the netdata user.

  sudo -u netdata -s

Run the go.d.plugin to debug the collector:

  ./go.d.plugin -d -m mysql

To debug a specific job:

  ./go.d.plugin -d -m mysql -j jobName

Getting Logs

If you're encountering problems with the mysql collector, follow these steps to retrieve logs and identify potential issues:

Run the command specific to your system (systemd, non-systemd, or Docker container).
Examine the output for any warnings or error messages that might indicate issues. These messages should provide clues about the root cause of the problem.

System with systemd

Use the following command to view logs generated since the last Netdata service restart:

journalctl _SYSTEMD_INVOCATION_ID="$(systemctl show --value --property=InvocationID netdata)" --namespace=netdata --grep mysql

System without systemd

Locate the collector log file, typically at /var/log/netdata/collector.log, and use grep to filter for collector's name:

grep mysql /var/log/netdata/collector.log

Note: This method shows logs from all restarts. Focus on the latest entries for troubleshooting current issues.

Docker Container

If your Netdata runs in a Docker container named "netdata" (replace if different), use this command:

docker logs netdata 2>&1 | grep mysql

#MariaDB

#Overview

#Default Behavior

#Auto-Detection

#Limits

#Performance Impact

#Setup

#Prerequisites

#Create netdata user

#Enable User Statistics (optional)

#Configuration

#Options

#via UI

#via File

#Examples

#TCP socket

#Unix socket

#Connection with password

#my.cnf

#Multi-instance

#Alerts

#Metrics

#Per MariaDB instance

#Per connection

#Per user

#Live Data

#Top Queries

#Prerequisites

#Enable performance_schema statement digest collection

#Grant SELECT permission on Performance Schema tables

#Parameters

#Returns

#Deadlock Info

#Prerequisites

#Enable deadlock-info function in Netdata

#Grant PROCESS privilege

#Parameters

#Returns

#Error Info

#Prerequisites

#Enable error-info function in Netdata

#Enable statement history consumers

#Grant SELECT on Performance Schema

#Parameters

#Returns

#Troubleshooting

#Debug Mode

#Getting Logs

#System with systemd

#System without systemd

#Docker Container

MariaDB

Overview

Default Behavior

Auto-Detection

Limits

Performance Impact

Setup

Prerequisites

Create netdata user

Enable User Statistics (optional)

Configuration

Options

via UI

via File

Examples

TCP socket

Unix socket

Connection with password

my.cnf

Multi-instance

Alerts

Metrics

Per MariaDB instance

Per connection

Per user

Live Data

Top Queries

Prerequisites

Enable performance_schema statement digest collection

Grant SELECT permission on Performance Schema tables

Parameters

Returns

Deadlock Info

Prerequisites

Enable deadlock-info function in Netdata

Grant PROCESS privilege

Parameters

Returns

Error Info

Prerequisites

Enable error-info function in Netdata

Enable statement history consumers

Grant SELECT on Performance Schema

Parameters

Returns

Troubleshooting

Debug Mode

Getting Logs

System with systemd

System without systemd

Docker Container