Performance Data

Starting from v3.0.0.0, TDengine provides the built-in database PERFORMANCE_SCHEMA for performance-related statistics. The sections below describe each table and its columns (aligned with the current system-table definitions).

Richer metadata and status information is also available via INFORMATION_SCHEMA (see Metadata) and the corresponding SHOW Commands.

PERF_APPS

Provides write/query statistics, slow-query counts, and last-access time for applications (clients) connected to the cluster. You can also query with SHOW APPS.

#	Column	Data Type	Description
1	app_id	UBIGINT	Client ID
2	ip	VARCHAR(16)	Client address
3	pid	INT	Client process ID
4	name	VARCHAR(24)	Client name
5	start_time	TIMESTAMP	Client start time
6	insert_req	UBIGINT	Number of INSERT requests
7	insert_row	UBIGINT	Number of rows inserted
8	insert_time	UBIGINT	INSERT request processing time, in microseconds
9	insert_bytes	UBIGINT	INSERT request message size in bytes
10	fetch_bytes	UBIGINT	Query result size in bytes
11	query_time	UBIGINT	Query request processing time
12	slow_query	UBIGINT	Number of slow queries (processing time ≥ 3 seconds)
13	total_req	UBIGINT	Total number of requests
14	current_req	UBIGINT	Number of requests currently being processed
15	last_access	TIMESTAMP	Last update time

PERF_CONNECTIONS

Provides user, client, login time, connection type, and token information for current database connections. You can also query with SHOW CONNECTIONS.

#	Column	Data Type	Description
1	conn_id	UINT	Connection ID
2	user	BINARY(24)	Username. Keyword column; escape with backticks when querying (e.g. `user`)
3	app	BINARY(24)	Client name
4	pid	UINT	Client process ID that initiated the connection
5	end_point	BINARY(134)	Client address
6	login_time	TIMESTAMP	Login time
7	last_access	TIMESTAMP	Last update time
8	user_app	BINARY(24)	User-side application name
9	user_ip	VARCHAR(22)	User-side IP
10	native_version	BINARY(32)	Native client version
11	connector_info	BINARY(256)	Connector information
12	type	BINARY(16)	Connection type
13	token	BINARY(32)	Token name (if logged in with a token)

PERF_CONSUMERS

Provides consumer group, status, subscribed topics, parameters, and last poll time for data-subscription consumers. You can also query with SHOW CONSUMERS.

#	Column	Data Type	Description
1	consumer_id	BINARY(32)	Unique consumer ID
2	consumer_group	BINARY(193)	Consumer group
3	client_id	BINARY(256)	Client identifier specified when creating the consumer
4	user	BINARY(24)	Username
5	fqdn	BINARY(128)	FQDN of the machine running the consumer
6	status	BINARY(20)	Current status: ready (available), lost (connection lost), rebalancing (vgroup assignment in progress), unknown
7	topics	BINARY(205)	Subscribed topics; multiple topics are shown as multiple rows
8	end_point	VARCHAR(22)	Endpoint
9	up_time	TIMESTAMP	Time of first connection to taosd
10	subscribe_time	TIMESTAMP	Time of the most recent subscribe request
11	rebalance_time	TIMESTAMP	Time of the most recent rebalance
12	parameters	BINARY(192)	Subscription parameters
13	poll_time	TIMESTAMP	Time of the most recent poll

PERF_INSTANCES

Provides registration information for instances connected to the cluster, including type, description, and registration/expiration times. You can also query with SHOW INSTANCES.

#	Column	Data Type	Description
1	id	VARCHAR(257)	ID
2	type	VARCHAR(66)	Type
3	desc	VARCHAR(514)	Instance description
4	first_reg_time	TIMESTAMP	First registration time
5	last_reg_time	TIMESTAMP	Most recent registration time
6	expire	INT	Expiration time (seconds)

PERF_QUERIES

Provides identifiers, elapsed time, phase status, and SQL text for queries currently running. You can also query with SHOW QUERIES.

#	Column	Data Type	Description
1	kill_id	VARCHAR(26)	ID used with KILL QUERY
2	query_id	UBIGINT	Query ID
3	conn_id	UINT	Connection ID
4	app	VARCHAR(24)	Application name
5	pid	INT	Process ID of the application on its host
6	user	VARCHAR(24)	Username
7	end_point	VARCHAR(22)	Client address
8	create_time	TIMESTAMP	Creation time
9	exec_usec	BIGINT	Elapsed execution time (microseconds)
10	stable_query	BOOL	Whether this is a supertable query
11	sub_query	BOOL	Whether this is a subquery
12	sub_num	INT	Number of subqueries
13	sub_status	VARCHAR(1000)	Subquery status (including subquery ID, status, and status start time)
14	sql	VARCHAR(2048)	SQL statement. Keyword column; escape with backticks when querying
15	user_app	VARCHAR(24)	User-side application name
16	user_ip	VARCHAR(22)	User-side IP
17	phase_state	VARCHAR(64)	Current query phase / status
18	phase_start_time	TIMESTAMP	Start time of the current phase

PERF_TRANS

Provides stage, operation target, failure count, and recent execution details for metadata transactions currently running. You can also query with SHOW TRANSACTIONS.

#	Column	Data Type	Description
1	id	BIGINT	Transaction ID
2	create_time	TIMESTAMP	Creation time
3	stage	VARCHAR(12)	Current stage (e.g. redoAction, undoAction, commit)
4	oper	VARCHAR(22)	Operator
5	db	VARCHAR(64)	Related database
6	stable	VARCHAR(192)	Related supertable
7	killable	VARCHAR(10)	Whether the transaction can be killed
8	failed_times	INT	Total number of execution failures
9	last_exec_time	TIMESTAMP	Last execution time
10	last_action_info	VARCHAR(511)	Details of the last failed execution
11	type	VARCHAR(10)	Transaction type