homework-jianmu/docs/en/14-reference/03-taos-sql/23-perf.md

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Performance Data /tdengine-reference/sql-manual/performance-data

Starting from TDengine 3.0, a built-in database performance_schema is provided, which stores performance-related statistical data. This section details the tables and table structures within it.

PERF_APP

Provides information about the applications (clients) accessing the cluster. You can also use SHOW APPS to query this information.

# Column Name Data Type Description
1 app_id UBIGINT Client ID
2 ip BINARY(16) Client address
3 pid INT Client process number
4 name BINARY(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 Processing time for insert requests, in microseconds
9 insert_bytes UBIGINT Byte size of insert request messages
10 fetch_bytes UBIGINT Byte size of query results
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

Information related to the database connections. You can also use SHOW CONNECTIONS to query this information.

# Column Name Data Type Description
1 conn_id INT Connection ID
2 user BINARY(24) Username
3 app BINARY(24) Client name
4 pid UINT Process number of the client initiating this connection on its server or host
5 end_point BINARY(128) Client address
6 login_time TIMESTAMP Login time
7 last_access TIMESTAMP Last update time

PERF_QUERIES

Provides information about the SQL statements that are currently being executed. You can also use SHOW QUERIES to query this information.

# Column Name Data Type Description
1 kill_id UBIGINT ID used to stop the query
2 query_id INT Query ID
3 conn_id UINT Connection ID
4 app BINARY(24) App name
5 pid INT Process number of the app on its host
6 user BINARY(24) Username
7 end_point BINARY(16) Client address
8 create_time TIMESTAMP Creation time
9 exec_usec BIGINT Execution time
10 stable_query BOOL Whether it is a supertable query
11 sub_num INT Number of subqueries
12 sub_status BINARY(1000) Subquery status
13 sql BINARY(1024) SQL statement

PERF_CONSUMERS

# Column Name Data Type Description
1 consumer_id BIGINT Unique ID of the consumer
2 consumer_group BINARY(192) Consumer group
3 client_id BINARY(192) User-defined string, displayed by specifying client_id when creating a consumer
4 status BINARY(20) Current status of the consumer. Consumer statuses include: ready (normally available), lost (connection lost), rebalancing (consumer's vgroup is being allocated), unknown (unknown status)
5 topics BINARY(204) Subscribed topics. If multiple topics are subscribed, they are displayed as multiple lines
6 up_time TIMESTAMP Time when first connected to taosd
7 subscribe_time TIMESTAMP Time when the last subscription was initiated
8 rebalance_time TIMESTAMP Time when the last rebalance was triggered

PERF_TRANS

# Column Name Data Type Description
1 id INT Identifier of the ongoing transaction
2 create_time TIMESTAMP Creation time of the transaction
3 stage BINARY(12) Current stage of the transaction, usually one of redoAction, undoAction, commit
4 db1 BINARY(64) Name of the first database that has a conflict with this transaction
5 db2 BINARY(64) Name of the second database that has a conflict with this transaction
6 failed_times INT Total number of times the transaction has failed
7 last_exec_time TIMESTAMP Last execution time of the transaction
8 last_action_info BINARY(511) Detailed information about the last failed execution of the transaction

PERF_SMAS

# Column Name Data Type Description
1 sma_name BINARY(192) Name of the time-range-wise sma (precomputed time dimension)
2 create_time TIMESTAMP Creation time of the sma
3 stable_name BINARY(192) Name of the supertable to which the sma belongs
4 vgroup_id INT Name of the vgroup dedicated to the sma