v1.1

Statistics Information Functions

Statistics information functions are divided into the following two categories: functions that access databases, using the OID of each table or index in a database to mark the database for which statistics are generated; functions that access servers, identified by the server process ID, whose value ranges from 1 to the number of currently active servers.

pg_stat_get_db_conflict_tablespace(oid)

Description: Number of queries canceled due to a conflict between the restored tablespace and the deleted tablespace in the database.

Return type: bigint
pg_control_group_config

Description: Prints cgroup configurations on the current node.

Return type: record
pg_stat_get_db_stat_reset_time(oid)

Description: Last time when database statistics were reset. It is initialized to the system time during the first connection to each database. The reset time is updated when you call pg_stat_reset on the database and execute pg_stat_reset_single_table_counters against any table or index in it.

Return type: timestamptz
pg_stat_get_function_total_time(oid)

Description: Total wall clock time spent in the function, in microseconds. The time spent on this function calling other functions is included.

Return type: bigint
pg_stat_get_xact_tuples_returned(oid)

Description: Number of rows read through sequential scans when the parameter is a table in the current transaction, or number of index entries returned when the parameter is an index.

Return type: bigint
pg_stat_get_xact_numscans(oid)

Description: Number of sequential scans performed when the parameter is a table in the current transaction, or number of index scans performed when the parameter is an index.

Return type: bigint
pg_stat_get_xact_blocks_fetched(oid)

Description: Number of disk block fetch requests for a table or index in the current transaction.

Return type: bigint
pg_stat_get_xact_blocks_hit(oid)

Description: Number of disk block fetch requests for tables or indexes found in cache in the current transaction.

Return type: bigint
pg_stat_get_xact_function_calls(oid)

Description: Number of times the function is called in the current transaction.

Return type: bigint
pg_stat_get_xact_function_self_time(oid)

Description: Time spent on this function in the current transaction, excluding the time spent on this function internally calling other functions.

Return type: bigint
pg_stat_get_xact_function_total_time(oid)

Description: Total wall clock time (in microseconds) spent on the function in the current transaction, including the time spent on this function internally calling other functions.

Return type: bigint

pg_stat_get_wal_senders()

Description: Queries walsender information on the primary server.

Return type: setofrecord

The following table describes return fields.

Table 1 Return field description

Field	Type	Description
pid	bigint	Thread ID of the WAL sender
sender_pid	integer	Lightweight thread ID of the WAL sender.
local_role	text	Type of the primary node
peer_role	text	Type of the standby node
peer_state	text	Status of the standby node
state	text	Status of the WAL sender
catchup_start	timestamp with time zone	Startup time of a catchup task
catchup_end	timestamp with time zone	End time of a catchup task
sender_sent_location	text	Sending position of the primary node
sender_write_location	text	Writing position of the primary node
sender_flush_location	text	Flushing position of the primary node
sender_replay_location	text	Redo position of the primary node
receiver_received_location	text	Receiving position of the standby node
receiver_write_location	text	Writing position of the standby node
receiver_flush_location	text	Flushing position of the standby node
receiver_replay_location	text	Redo position of the standby node
sync_percent	text	Synchronization percentage
sync_state	text	Synchronization status
sync_priority	text	Priority of synchronous replication
sync_most_available	text	Maximum availability mode
channel	text	Channel information of the WAL sender

pg_stat_get_stream_replications()

Description: Queries the primary/standby replication status.

Return type: setofrecord

The following table describes return values.

Table 2 Return value description

Return Parameter Type Description

local_role text Local role

static_connections integer Connection statistics

db_state text Database status

detail_information text Detailed information
pg_stat_get_db_numbackends(oid)

Description: Number of active server processes for a database

Return type: integer
pg_stat_get_db_xact_commit(oid)

Description: Number of transactions committed in a database

Return type: bigint
pg_stat_get_db_xact_rollback(oid)

Description: Number of transactions rolled back in a database

Return type: bigint
pg_stat_get_db_blocks_fetched(oid)

Description: Number of disk blocks fetch requests for a database

Return type: bigint
pg_stat_get_db_blocks_hit(oid)

Description: Number of disk block fetch requests found in cache for a database

Return type: bigint
pg_stat_get_db_tuples_returned(oid)

Description: Number of tuples returned for a database

Return type: bigint
pg_stat_get_db_tuples_fetched(oid)

Description: Number of tuples fetched for a database

Return type: bigint
pg_stat_get_db_tuples_inserted(oid)

Description: Number of tuples inserted in a database

Return type: bigint
pg_stat_get_db_tuples_updated(oid)

Description: Number of tuples updated in a database

Return type: bigint
pg_stat_get_db_tuples_deleted(oid)

Description: Number of tuples deleted in a database

Return type: bigint
pg_stat_get_db_conflict_lock(oid)

Description: Number of lock conflicts in a database

Return type: bigint
pg_stat_get_db_deadlocks(oid)

Description: Number of deadlocks in a database

Return type: bigint
pg_stat_get_numscans(oid)

Description: Number of sequential row scans done if parameters are in a table or number of index scans done if parameters are in an index

Return type: bigint
pg_stat_get_role_name(oid)

Description: Obtains the username based on the user OID. Only the sysadmin and monitor admin users can access.

Return type: text

Example:
```
mogdb=# select pg_stat_get_role_name(10);
 pg_stat_get_role_name
-----------------------
 aabbcc
(1 row)
```
pg_stat_get_tuples_returned(oid)

Description: Number of sequential row scans done if parameters are in a table or number of index entries returned if parameters are in an index

Return type: bigint
pg_stat_get_tuples_fetched(oid)

Description: Number of table rows fetched by bitmap scans if parameters are in a table, or table rows fetched by simple index scans using the index if parameters are in an index

Return type: bigint
pg_stat_get_tuples_inserted(oid)

Description: Number of rows inserted into table

Return type: bigint
pg_stat_get_tuples_updated(oid)

Description: Number of rows updated in table

Return type: bigint
pg_stat_get_tuples_deleted(oid)

Description: Number of rows deleted from table

Return type: bigint
pg_stat_get_tuples_changed(oid)

Description: Total number of inserted, updated, and deleted rows after the table was last analyzed or autoanalyzed

Return type: bigint
pg_stat_get_tuples_hot_updated(oid)

Description: Number of rows hot updated in table

Return type: bigint
pg_stat_get_live_tuples(oid)

Description: Number of live rows in table

Return type: bigint
pg_stat_get_dead_tuples(oid)

Description: Number of dead rows in table

Return type: bigint
pg_stat_get_blocks_fetched(oid)

Description: Number of disk block fetch requests for table or index

Return type: bigint
pg_stat_get_blocks_hit(oid)

Description: Number of disk block requests found in cache for table or index

Return type: bigint
pg_stat_get_partition_tuples_inserted(oid)

Description: Number of rows in the corresponding table partition

Return type: bigint
pg_stat_get_partition_tuples_updated(oid)

Description: Number of rows that have been updated in the corresponding table partition

Return type: bigint
pg_stat_get_partition_tuples_deleted(oid)

Description: Number of rows deleted from the corresponding table partition

Return type: bigint
pg_stat_get_partition_tuples_changed(oid)

Description: Total number of inserted, updated, and deleted rows after the table partition was last analyzed or autoanalyzed

Return type: bigint
pg_stat_get_partition_live_tuples(oid)

Description: Number of live rows in partitioned table

Return type: bigint
pg_stat_get_partition_dead_tuples(oid)

Description: Number of dead rows in partitioned table

Return type: bigint
pg_stat_get_xact_tuples_inserted(oid)

Description: Number of tuple inserted into the active subtransactions related to the table.

Return type: bigint
pg_stat_get_xact_tuples_deleted(oid)

Description: Number of deleted tuples in the active subtransactions related to a table

Return type: bigint
pg_stat_get_xact_tuples_hot_updated(oid)

Description: Number of hot updated tuples in the active subtransactions related to a table

Return type: bigint
pg_stat_get_xact_tuples_updated(oid)

Description: Number of updated tuples in the active subtransactions related to a table

Return type: bigint
pg_stat_get_xact_partition_tuples_inserted(oid)

Description: Number of inserted tuples in the active subtransactions related to a table partition

Return type: bigint
pg_stat_get_xact_partition_tuples_deleted(oid)

Description: Number of deleted tuples in the active subtransactions related to a table partition

Return type: bigint
pg_stat_get_xact_partition_tuples_hot_updated(oid)

Description: Number of hot updated tuples in the active subtransactions related to a table partition

Return type: bigint
pg_stat_get_xact_partition_tuples_updated(oid)

Description: Number of updated tuples in the active subtransactions related to a table partition

Return type: bigint
pg_stat_get_last_vacuum_time(oid)

Description: Last time when the autovacuum thread is manually started to clear a table

Return type: timestamptz
pg_stat_get_last_autovacuum_time(oid)

Description: Time of the last vacuum initiated by the autovacuum daemon on this table

Return type: timestamptz
pg_stat_get_vacuum_count(oid)

Description: Number of times a table is manually cleared

Return type: bigint
pg_stat_get_autovacuum_count(oid)

Description: Number of times the autovacuum daemon is started to clear a table

Return type: bigint
pg_stat_get_last_analyze_time(oid)

Description: Last time when a table starts to be analyzed manually or by the autovacuum thread

Return type: timestamptz
pg_stat_get_last_autoanalyze_time(oid)

Description: Time of the last analysis initiated by the autovacuum daemon on this table

Return type: timestamptz
pg_stat_get_analyze_count(oid)

Description: Number of times a table is manually analyzed

Return type: bigint
pg_stat_get_autoanalyze_count(oid)

Description: Number of times the autovacuum daemon analyzes a table

Return type: bigint

Return Parameter	Type	Description
local_role	text	Local role
static_connections	integer	Connection statistics
db_state	text	Database status
detail_information	text	Detailed information

pg_total_autovac_tuples(bool,bool)

Description: Returns tuple records related to the total autovac, such as nodename, nspname, relname, and tuple IUDs. The input parameters specify whether to query relation and local information, respectively.

Return type: setofrecord

The following table describes return parameters.

Table 3 Return parameter description

Return Parameter	Type	Description
nodename	name	Node name
nspname	name	Name of a namespace
relname	name	Name of an object, such as a table, index, or view
partname	name	Partition name
n_dead_tuples	bigint	Number of dead rows in a table partition
n_live_tuples	bigint	Number of live rows in a table partition
changes_since_analyze	bigint	Number of changes generated by ANALYZE

pg_autovac_status(oid)

Description: Returns autovac information, such as nodename, nspname, relname, analyze, vacuum, thresholds of analyze and vacuum, and the number of analyzed or vacuumed tuples. Only the sysadmin user can use this function.

Return type: setofrecord

The following table describes return parameters.

Table 4 Return parameter description

Return Parameter	Type	Description
nspname	text	Name of a namespace
relname	text	Name of an object, such as a table, index, or view
nodename	text	Node name
doanalyze	Boolean	Whether to execute ANALYZE
anltuples	bigint	Number of ANALYZE tuples
anlthresh	bigint	ANALYZE threshold
dovacuum	Boolean	Whether to execute VACUUM
vactuples	bigint	Number of VACUUM tuples
vacthresh	bigint	VACUUM threshold

pg_autovac_timeout(oid)

Description: Returns the number of consecutive timeouts during the autovac operation on a table. If the table information is invalid or the node information is abnormal, NULL will be returned.

Return type: bigint
pg_autovac_dbnode(oid)

Description: Returns the name of the dbnode performing the autovac operation on a table. If the table information is invalid or the node information is abnormal, NULL will be returned.

Return type: text
pg_stat_get_last_data_changed_time(oid)

Description: Returns the time when INSERT, UPDATE, DELETE, or EXCHANGE/TRUNCATE/DROP PARTITION was performed last time on a table. The data in the last_data_changed column of the PG_STAT_ALL_TABLES view is calculated by using this function. The performance of obtaining the last modification time by using the view is poor when the table has a large amount of data. In this case, you are advised to use the function.

Return type: timestamptz
pg_stat_set_last_data_changed_time(oid)

Description: Manually changes the time when INSERT, UPDATE, DELETE, or EXCHANGE/TRUNCATE/DROP PARTITION was performed last time.

Return type: void
pg_backend_pid()

Description: Thread ID of the server thread attached to the current session

Return type: integer

pg_stat_get_activity(integer)

Description: Returns a record about the backend with the specified PID. A record for each active backend in the system is returned if NULL is specified. The return results are a subnet of those (excluding the connection_info column) in the PG_STAT_ACTIVITY view.

Example:

mogdb=# select * from pg_stat_get_activity(140036483839744);
 datid |       pid       |    sessionid    | usesysid | application_name | state  |                        query                         | waiting |          xact_start
       |          query_start          |         backend_start         |         state_change          | client_addr | client_hostname | client_port | enqueue |     query_i
d
-------+-----------------+-----------------+----------+------------------+--------+------------------------------------------------------+---------+------------------------
-------+-------------------------------+-------------------------------+-------------------------------+-------------+-----------------+-------------+---------+------------
-------
 15914 | 140036483839744 | 140036483839744 |       10 | gsql             | active | select * from pg_stat_get_activity(140036483839744); | f       | 2020-06-24 10:53:19.583
666+08 | 2020-06-24 10:53:19.583598+08 | 2020-06-24 10:00:03.471893+08 | 2020-06-24 10:53:19.583601+08 |             |                 |          -1 |         | 72902018968
108794
(1 row)

Return type: setofrecord

The following table describes return parameters.

Table 5 Return parameter description

Return Parameter	Type	Description
datid	oid	OID of the database that the user session connects to in the backend
pid	bigint	Thread ID of the backend
sessionid	bigint	Session ID
usesysid	oid	Name of the user logged in to the backend
application_name	text	Name of the application connected to the backend
state	text	Overall status of this backend.
query	text	Text of this backend's most recent query. If state is active, this column shows the ongoing query. In all other states, it shows the last query that was executed.
waiting	Boolean	Whether the backend is currently waiting on a lock. If yes, the value is true.
xact_start	timestamp with time zone	Time when current transaction was started (null if no transaction is active).If the current query is the first of its transaction, the value of this column is the same as that of the query_start column.
query_start	timestamp with time zone	Time when the currently active query was started, or time when the last query was started if state is not active
backend_start	timestamp with time zone	Time when this process was started, that is, when the client connected to the server
state_change	timestamp with time zone	Time when the state was last changed
client_addr	inet	IP address of the client connected to the backend. If this column is NULL, it indicates either the client is connected via a Unix socket on the server or this is an internal process, such as AUTOVACUUM.
client_hostname	text	Host name of the connected client, as reported by a reverse DNS lookup of client_addr. This column will be non-null only for IP connections and only when log_hostname is enabled.
client_port	integer	TCP port number that the client uses for communication with this backend (-1 if a Unix socket is used)
enqueue	text	Unsupported currently
query_id	bigint	ID of a query

pg_stat_get_activity_with_conninfo(integer)

Return type: setofrecord

The following table describes return values.

Table 6 Return value description

Return Value	Return Type	Description
datid	oid	OID of the database that the user session connects to in the backend
pid	bigint	Thread ID of the backend
sessionid	bigint	Session ID
usesysid	oid	Name of the user logged in to the backend
application_name	text	Name of the application connected to the backend
state	text	Overall status of this backend
query	text	Text of this backend's most recent query. If state is active, this column shows the ongoing query. In all other states, it shows the last query that was executed.
waiting	Boolean	Whether the backend is currently waiting on a lock. If yes, the value is true
xact_start	timestamp with time zone	Time when current transaction was started (null if no transaction is active). If the current query is the first of its transaction, the value of this column is the same as that of the query_start column.
query_start	timestamp with time zone	Time when the currently active query was started, or time when the last query was started if state is not active
backend_start	timestamp with time zone	Time when this process was started, that is, when the client connected to the server
state_change	timestamp with time zone	Time when the state was last changed
client_addr	inet	IP address of the client connected to the backend. If this column is NULL, it indicates either the client is connected via a Unix socket on the server or this is an internal process, such as AUTOVACUUM.
client_hostname	text	Host name of the connected client, as reported by a reverse DNS lookup of client_addr. This column will be non-null only for IP connections and only when log_hostname is enabled.
client_port	integer	TCP port number that the client uses for communication with this backend (-1 if a Unix socket is used)
enqueue	text	Unsupported currently
query_id	bigint	ID of a query
connection_info	text	A string in JSON format recording the driver type, driver version, driver deployment path, and process owner of the connected database

pg_user_iostat(text)

Description: Displays the I/O load management information about the job currently executed by the user.

Return type: record

The following table describes return fields.

Name	Type	Description
userid	oid	User ID.
min_curr_iops	int4	Minimum I/O of the current user across database nodes. The IOPS is counted by ones for column storage and by ten thousands for row storage.
max_curr_iops	int4	Maximum I/O of the current user across database nodes. The IOPS is counted by ones for column storage and by thousands for row storage.
min_peak_iops	int4	Minimum peak I/O of the current user across database nodes. The IOPS is counted by ones for column storage and by thousands for row storage.
max_peak_iops	int4	Maximum peak I/O of the current user across database nodes. The IOPS is counted by ones for column storage and by thousands for row storage.
io_limits	int4	io_limits set for the resource pool specified by the user. The IOPS is counted by ones for column storage and by thousands for row storage.
io_priority	text	io_priority set for the user. The IOPS is counted by ones for column storage and by thousands for row storage.

pg_stat_get_function_calls(oid)

Description: Number of times the function has been called

Return type: bigint
pg_stat_get_function_self_time(oid)

Description: Time spent in only this function. The time spent on this function calling other functions is excluded.

Return type: bigint
pg_stat_get_backend_idset()

Description: Set of currently active server process numbers (from 1 to the number of active server processes)

Return type: setofinteger
pg_stat_get_backend_pid(integer)

Description: Thread ID of the given server thread

Return type: bigint
pg_stat_get_backend_dbid(integer)

Description: ID of the database connected to the given server process

Return type: oid
pg_stat_get_backend_userid(integer)

Description: User ID of the given server process

Return type: oid
pg_stat_get_backend_activity(integer)

Description: Active command of the given server process, but only if the current user is a system administrator or the same user as that of the session being queried and track_activities is on

Return type: text
pg_stat_get_backend_waiting(integer)

Description: True if the given server process is waiting for a lock, but only if the current user is a system administrator or the same user as that of the session being queried and track_activities is on

Return type: Boolean
pg_stat_get_backend_activity_start(integer)

Description: The time at which the given server process's currently executing query was started, but only if the current user is a system administrator or the same user as that of the session being queried and track_activities is on

Return type: timestamp with time zone
pg_stat_get_backend_xact_start(integer)

Description: The time at which the given server process's currently executing transaction was started, but only if the current user is a system administrator or the same user as that of the session being queried and track_activities is on

Return type: timestamp with time zone
pg_stat_get_backend_start(integer)

Description: The time at which the given server process was started, or NULL if the current user is neither a system administrator nor the same user as that of the session being queried

Return type: timestamp with time zone
pg_stat_get_backend_client_addr(integer)

Description: IP address of the client connected to the given server process. If the connection is over a Unix domain socket, or if the current user is neither a system administrator nor the same user as that of the session being queried, NULL will be returned.

Return type: inet
pg_stat_get_backend_client_port(integer)

Description: TCP port number of the client connected to the given server process If the connection is over a Unix domain socket, -1 will be returned. If the current user is neither a system administrator nor the same user as that of the session being queried, NULL will be returned.

Return type: integer
pg_stat_get_bgwriter_timed_checkpoints()

Description: The number of times the background writer has started timed checkpoints (because the checkpoint_timeout time has expired)

Return type: bigint
pg_stat_get_bgwriter_requested_checkpoints()

Description: The number of times the background writer has started checkpoints based on requests from the backend because checkpoint_segments has been exceeded or the CHECKPOINT command has been executed

Return type: bigint
pg_stat_get_bgwriter_buf_written_checkpoints()

Description: The number of buffers written by the background writer during checkpoints

Return type: bigint
pg_stat_get_bgwriter_buf_written_clean()

Description: The number of buffers written by the background writer for routine cleaning of dirty pages

Return type: bigint
pg_stat_get_bgwriter_maxwritten_clean()

Description: The number of times the background writer has stopped its cleaning scan because it has written more buffers than specified in the bgwriter_lru_maxpages parameter

Return type: bigint
pg_stat_get_buf_written_backend()

Description: The number of buffers written by the backend because they needed to allocate a new buffer

Return type: bigint
pg_stat_get_buf_alloc()

Description: The total number of buffer allocations

Return type: bigint
pg_stat_clear_snapshot()

Description: Discards the current statistics snapshot.

Return type: void
pg_stat_reset()

Description: Resets all statistics counters for the current database to zero (requires system administrator permissions).

Return type: void
gs_stat_reset()

Description: Resets all statistics counters for the current database on each node to zero (requires system administrator permissions).

Return type: void
pg_stat_reset_shared(text)

Description: Resets all statistics counters for the current database in each node in a shared cluster to zero (requires system administrator permissions).

Return type: void
pg_stat_reset_single_table_counters(oid)

Description: Resets statistics for a single table or index in the current database to zero (requires system administrator permissions).

Return type: void
pg_stat_reset_single_function_counters(oid)

Description: Resets statistics for a single function in the current database to zero (requires system administrator permissions).

Return type: void
pg_stat_session_cu(int, int, int)

Description: Obtains the compression unit (CU) hit statistics of sessions running on the current node.

Return type: record
gs_get_stat_session_cu(text, int, int, int)

Description: Obtains the CU hit statistics of all running sessions in MogDB.

Return type: record
gs_get_stat_db_cu(text, text, int, int, int)

Description: Obtains the CU hit statistics of a database in MogDB.

Return type: record
pg_stat_get_cu_mem_hit(oid)

Description: Obtains the number of CU memory hits of a column storage table in the current database of the current node.

Return type: bigint
pg_stat_get_cu_hdd_sync(oid)

Description: Obtains the times CU is synchronously read from a disk by a column storage table in the current database of the current node.

Return type: bigint
pg_stat_get_cu_hdd_asyn(oid)

Description: Obtains the times CU is asynchronously read from a disk by a column storage table in the current database of the current node.

Return type: bigint
pg_stat_get_db_cu_mem_hit(oid)

Description: Obtains the CU memory hit in a database of the current node.

Return type: bigint
pg_stat_get_db_cu_hdd_sync(oid)

Description: Obtains the times CU is synchronously read from a disk by a database of the current node.

Return type: bigint
pgxc_get_wlm_current_instance_info(text, int default null)

Description: Queries the current resource usage on the primary database node and reads the data that is not stored in section "5.19.2.3 GS_WLM_INSTANCE_HISTORY" system catalog in the memory. The input parameters are the node name (ALL, C, D, or instance name) and the maximum number of records returned by each node. The returned value is GS_WLM_INSTANCE_HISTORY.

Return type: setofrecord
pgxc_get_wlm_history_instance_info(text, TIMESTAMP, TIMESTAMP, int default null)

Description: Queries the historical resource usage on the primary database node and reads the data in section "GS_WLM_INSTANCE_HISTORY" system catalog in the memory. The input parameters are as follows: node name (ALL, C, D, or instance name), start time, end time, and maximum number of records returned for each instance. The returned value is GS_WLM_INSTANCE_HISTORY.

Return type: setofrecord
fenced_udf_process()

Description: Shows the number of local UDF Master and Work processes.

Return type: record
total_cpu()

Description: Obtains the CPU time used by the current node, in jiffies.

Return type: bigint
total_memory()

Description: Obtains the size of the virtual memory used by the current node, in KB.

Return type: bigint
pg_stat_get_db_cu_hdd_asyn(oid)

Description: Obtains the times CU is asynchronously read from a disk by a database of the current node.

Return type: bigint
pg_stat_bad_block(text, int, int, int, int, int, timestamp with time zone, timestamp with time zone)

Description: Obtains damage information about pages or CUs after the current node is started.

Example: select * from pg_stat_bad_block();

Return type: record
pg_stat_bad_block_clear()

Description: Deletes the page and CU damage information that is read and recorded on the node. (System administrator rights are required.)

Return type: void
gs_respool_exception_info(pool text)

Description: Queries for the query rule of a specified resource pool.

Return type: record

gs_control_group_info(pool text)

Description: Queries for information about Cgroups associated with a resource pool.

Return type: record

The following table describes return fields.

Attribute	Attribute Value	Description
name	class_a:workload_a1	Name of class and workload
class	class_a	Class Cgroup name
workload	workload_a1	Workload Cgroup name
type	DEFWD	Cgroup type (Top, CLASS, BAKWD, DEFWD, and TSWD)
gid	87	Cgroup ID
shares	30	Percentage of CPU resources to those on the parent node
limits	0	Percentage of CPU cores to those on the parent node
rate	0	Allocation raio in Timeshare
cpucores	0-3	CPU cores

gs_all_control_group_info()

Description: Collects information about all Cgroups in the database.

Return type: record
gs_get_control_group_info()

Description: Collects information about all Cgroups.

Return type: record

get_instr_workload_info(integer)

Description: Obtains the transaction volume and time information on the primary database node.

Return type: record

Attribute	Attribute Value	Description
resourcepool_oid	10	OID of the resource pool (the logic is equivalent to the load)
commit_counter	4	Number of front-end transactions that were committed
rollback_counter	1	Number of front-end transactions that were rolled back
resp_min	949	Minimum response time of front-end transactions (unit: μs)
resp_max	201891	Maximum response time of front-end transactions (unit: μs)
resp_avg	43564	Average response time of front-end transactions (unit: μs)
resp_total	217822	Total response time of front-end transactions (unit: μs)
bg_commit_counter	910	Number of background transactions that were committed
bg_rollback_counter	0	Number of background transactions that were rolled back
bg_resp_min	97	Minimum response time of background transactions (unit: μs)
bg_resp_max	678080687	Maximum response time of background transactions (unit: μs)
bg_resp_avg	327847884	Average response time of background transactions (unit: μs)
bg_resp_total	298341575300	Total response time of background transactions (unit: μs)

pv_instance_time()

Description: Obtains the time consumed in each execution phase on the current node.

Return type: record

Stat_name Attribute	Attribute Value	Description
DB_TIME	1062385	Total end-to-end wall time consumed by all threads (unit: μs)
CPU_TIME	311777	Total CPU time consumed by all threads (unit: μs)
EXECUTION_TIME	380037	Total time consumed on the executor (unit: μs)
PARSE_TIME	6033	Total time consumed for parsing SQL statements (unit: μs)
PLAN_TIME	173356	Total time consumed for generating an execution plan (unit: μs)
REWRITE_TIME	2274	Total time consumed on query rewriting (unit: μs)
PL_EXECUTION_TIME	0	Total time consumed for executing PL/SQL statements (unit: μs)
PL_COMPILATION_TIME	557	Total time consumed for SQL compilation (unit: μs)
NET_SEND_TIME	1673	Total time consumed for sending data over network (unit: μs)
DATA_IO_TIME	426622	Total time consumed for data read and write (unit: μs)

DBE_PERF.get_global_instance_time()

Description: Provides the time consumption of each key phase of MogDB. This function is supported only on the primary node of the database. To query this function, you must have the sysadmin permission.

Return type: record
get_instr_unique_sql()

Description: Obtains information about execution statements (normalized SQL statements) on the current node as a user with the sysadmin permission.

Return type: record
reset_unique_sql(text, text, bigint)

Description: Resets information about system execution statements (normalized SQL statements) information as a user with the sysadmin permission. The value of the first parameter can be global or local. global indicates that information on all nodes is cleared, and local indicates that only information on the current node is cleared. The value of the second parameter can be ALL, BY_USERID, or BY_CNID. ALL indicates that all information is cleared. BY_USERID indicates that the SQL information of the user specified by USERID is cleared. BY_CNID indicates that the SQL information related to the primary node of the database in the system is cleared. The third parameter indicates CNID and USERID. If the second parameter is set to ALL, the third parameter does not take effect and can be set to any value.

Return type: Boolean
get_instr_wait_event(NULL)

Description: Obtains the statistics on wait events of the current node.

Return type: record
get_instr_user_login()

Description: Obtains the number of user login and logout times of the current node as a user with the sysadmin permission.

Return type: record
get_instr_rt_percentile()

Description: Obtains the response time distribution for 80% and 95% SQL statements in the CCN node. This information of MogDB is stored on the CCN node. The query result from other nodes is 0.

Return type: record
get_node_stat_reset_time()

Description: Obtains statistics about reset (restart, primary/standby switchover, and database deletion) time of the current node.

Return type: record
DBE_PERF.get_global_os_runtime()

Description: Displays the running status of the current OS. This function is supported only on the primary node of the database. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_global_os_threads()

Description: Provides information about the threads under all normal nodes of MogDB. This function is supported only on the primary node of the database. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_summary_workload_sql_count()

Description: Provides statistics about the number of SELECT, UPDATE, INSERT, DELETE, DDL, DML, and DCL statements of different service loads in MogDB. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_summary_workload_sql_elapse_time()

Description: Provides statistics about the number of SELECT, UPDATE, INSERT, and DELETE statements and response time information (TOTAL, AVG, MIN, and MAX) for different loads in MogDB. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_global_workload_transaction()

Description: Obtains the transaction volume and time information on all nodes of MogDB. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_global_session_stat()

Description: Obtains the session status information on all nodes of MogDB. To query this function, you must have the sysadmin permission.

Return type: record

NOTE:

The status information contains the following 17 items:commit, rollback, sql, table_scan, blocks_fetched, physical_read_operation, shared_blocks_dirtied, local_blocks_dirtied, shared_blocks_read, local_blocks_read, blocks_read_time, blocks_write_time, sort_imemory, sort_idisk, cu_mem_hit, cu_hdd_sync_read, and cu_hdd_asyread.
DBE_PERF.get_global_session_time()

Description: Provides the time consumed in each key phase of each node in MogDB. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_global_session_memory()

Description: Displays statistics about memory usage at the session level on each node in the unit of MB, including all the memory allocated to Postgres and stream threads on DNs for jobs currently executed by users. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_global_session_memory_detail()

Description: Displays statistics about thread memory usage on each node by MemoryContext node. To query this function, you must have the sysadmin permission.

Return type: record
gs_session_memory_detail_tp()

Description: Collects statistics about thread memory usage by MemoryContext node. When enable_thread_pool is set to on, this view contains memory usage of all threads and sessions.

Return type: record
reate_wlm_operator_info(int flag)

Description: Clears top SQL operator-level statistics recorded in the current memory. If the input parameter is greater than 0, the information is archived to gs_wlm_operator_info and gs_wlm_ec_operator_info. Otherwise, the information is not archived. Only the administrator can execute this function.

Return type: int
create_wlm_session_info(int flag)

Description: Clears top SQL query statement-level statistics recorded in the current memory. Only the administrator can execute this function.

Return type: int
pg_stat_get_wlm_session_info(int flag)

Description: Obtains top SQL query statement-level statistics recorded in the current memory. If the input parameter is not 0, the information is cleared from the memory. Only the system admin and monitor admin users can execute this function.

Return type: record
gs_wlm_get_resource_pool_info()

Description: Obtains the resource usage statistics of all users.

Return type: record
gs_wlm_get_all_user_resource_info()

Description: Obtains the resource usage statistics of all users.

Return type: record
gs_wlm_get_user_info()

Description: Obtains information about all users.

Return type: record
gs_wlm_get_workload_records()

Description: Obtains all job information in dynamic load management. This function is valid only when dynamic load management is enabled.

Return type: record
gs_wlm_persisitent_user_resource_info()

Description: Archives all user resource usage statistics to the gs_wlm_user_resource_history system catalog.

Return type: record
gs_wlm_readjust_user_space()

Description: Corrects the storage space usage of all users. Only the administrator can execute this function.

Return type: record
gs_wlm_readjust_user_space_through_username(text name)

Description: Corrects the storage space usage of a specified user. Common users can use this function to modify only their own usage. Only the administrator can modify the usage of all users. If the value of name is 0000, the usage of all users needs to be modified.

Return type: record
gs_wlm_readjust_user_space_with_reset_flag(text name, boolean isfirst)

Description: Corrects the storage space usage of a specified user. If the input parameter isfirst is set to true, statistics are collected from 0. Otherwise, statistics are collected from the previous result. Common users can use this function to modify only their own usage. Only the administrator can modify the usage of all users. If the value of name is 0000, the usage of all users needs to be modified.

Return type: record
gs_wlm_session_respool()

Description: Obtains the session resource pool information about all background threads.

Return type: record
gs_wlm_get_session_info()

Description: This API has been discarded and is unavailable currently.
gs_wlm_get_user_session_info()

Description: This API has been discarded and is unavailable currently.
gs_total_nodegroup_memory_detail

Description: Returns information about the memory used by the current logical cluster in the database, in MB.

Return type: SETOF record
global_comm_client_info()

Description: Queries information about active client connections of global nodes. For details about the columns returned by the function, see the COMM_CLIENT_INFO column.

Return type: record
pgxc_get_wlm_ec_operator_history()

Description: Displays the operator information when the execution of ExtensionConnector (EC) jobs cached on all primary nodes is complete. The information is cleared every 3 minutes. Only the system administrator can execute this function.

Return type: record
pgxc_get_wlm_ec_operator_info()

Description: Displays the operator information when the execution of ExtensionConnector (EC) jobs on all primary nodes is complete. Only the system administrator can execute this function.

Return type: record
pgxc_get_wlm_ec_operator_statistics()

Description: Displays the operator information when ExtensionConnector (EC) jobs on all primary nodes are being executed. Only the system administrator can execute this function.

Return type: record
pgxc_get_wlm_operator_history()

Description: Displays the operator information when the execution of jobs cached on all primary nodes is complete. The information is cleared every 3 minutes. Only the system administrator can execute this function.

Return type: record
pgxc_get_wlm_operator_info()

Description: Displays the operator information when the execution of jobs on all primary nodes is complete. Only the system administrator can execute this function.

Return type: record
pgxc_get_wlm_operator_statistics()

Description: Displays the operator information when jobs on all primary nodes are being executed. Only the system administrator can execute this function.

Return type: record
pgxc_get_wlm_session_history()

Description: Displays the load management information when the execution of jobs cached on all primary nodes is complete. The information is cleared every 3 minutes. Only the system administrator can execute this function.

Return type: record
pgxc_get_wlm_session_info()

Description: Displays the load management information when the execution of jobs cached on all primary nodes is complete. Only the system administrator can execute this function.

Return type: record
pgxc_get_wlm_session_info_bytime(tag text, begin timestamp, end timestamp, limit int)

Description: Displays load management records of jobs whose start or end time is within a time range on all primary nodes. Only the system administrator can execute this function.

Parameter description:
- tag: The value can only be 'start_time' or 'finish_time', indicating that the query is restricted by the start time or end time of the job.
- begin: start time of a time range.
- end: end time of a time range.
- limit: number of returned records.
  
  Return type: record
pgxc_get_wlm_session_statistics()

Description: Displays load management records when jobs on all primary nodes are being executed. Only the system administrator can execute this function.

Return type: record
pgxc_stat_activity_with_conninfo()

Description:PGXC_STAT_ACTIVITY shows query information about the current user on all the CNs in the current cluster. Only the system administrator has the permission to query this view.

Return type: SETOF record
pgxc_wlm_get_workload_records()

Description: Displays the status information when jobs on all primary nodes are being executed. Only the system administrator can execute this function.

Return type: record
DBE_PERF.get_global_active_session()

Description: Displays a summary of samples in the ACTIVE SESSION PROFILE memory on all nodes.

Return type: record
DBE_PERF.get_global_session_stat_activity()

Description: Displays information about threads that are running on each node in MogDB. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_global_thread_wait_status()

Description: Displays the block waiting status of backend threads and auxiliary threads on all nodes. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_wlm_user_resource_runtime()

Description: Displays the resource usage of all users. This parameter is valid only when use_workload_manager is set to on. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_global_operator_history_table()

Description: Displays the operator-related records (persistent) generated after jobs are executed on the primary database node of the current user. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_global_operator_history()

Description: Displays the operator-related records generated after jobs are executed on the primary database node of the current user. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_global_operator_runtime()

Description: Displays real-time operator-related records of jobs executed on the primary database node of the current user. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_global_statement_complex_history()

Description: Displays the historical records of complex queries on the primary database node of the current user. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_global_statement_complex_history_table()

Description: Displays the historical records (persistent) of complex queries on the primary database node of the current user. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_global_statement_complex_runtime()

Description: Displays the real-time information of complex queries on the primary database node of the current user. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_global_memory_node_detail()

Description: Displays the memory usage of a certain database on all nodes. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_global_shared_memory_detail()

Description: Displays the usage information about all the shared memory contexts of all nodes. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_global_statio_all_indexes

Description: Displays statistics about each index displayed in a row in the current database, showing I/O statistics about accesses to that specific index. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_local_toastname_and_toastindexname()

Description: Provides the mapping between the name and index of the local TOAST table and its associated tables.

Return type: record
DBE_PERF.get_summary_statio_all_indexes()

Description: Collects statistics about each index displayed in a row in the current databases of all nodes and displays the I/O statistics of a specific index. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_global_statio_all_sequences()

Description: Provides I/O status information about all sequences in the namespace. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_global_statio_all_tables()

Description: Displays the I/O statistics about each table in databases on each node as a user with the sysadmin permission.

Return type: record
DBE_PERF.get_summary_statio_all_tables()

Description: Collects I/O statistics about each table in databases in MogDB. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_local_toast_relation()

Description: Provides the mapping between the name of the local toast table and its associated table. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_global_statio_sys_indexes()

Description: Displays the I/O status information about all system catalog indexes in namespaces on each node. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_summary_statio_sys_indexes()

Description: Collects the I/O status information about all system catalog indexes in namespaces on each node. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_global_statio_sys_sequences()

Description: Provides the I/O status information about all the system sequences in the namespace. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_global_statio_sys_tables()

Description: Provides I/O status information about all system catalogs in namespaces on each node. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_summary_statio_sys_tables()

Description: Displays the I/O status information of all system catalogs in the namespace in MogDB. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_global_statio_user_indexes()

Description: Displays the I/O status information about all user relationship table indexes in namespaces on each node. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_summary_statio_user_indexes()

Description: Displays the I/O status information about all user relationship table indexes in namespaces in MogDB. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_global_statio_user_sequences()

Description: Displays the I/O status information about all user sequences in the namespace of each node. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_global_statio_user_tables()

Description: Displays the displays I/O status information about all user relationship tables in namespaces on each node. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_summary_statio_user_tables()

Description: Displays the I/O status information about all user relationship tables in namespaces in MogDB. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_stat_db_cu()

Description: Queries CU hits in a database and in each node in MogDB. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_global_stat_all_indexes()

Description: Displays statistics of each index in databases on all nodes. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_summary_stat_all_indexes()

Description: Collects statistics on each index in all databases on all nodes. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_global_stat_sys_tables()

Description: Displays statistics about the system catalogs of all the namespaces in pg_catalog and information_schema schemas on each node. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_summary_stat_sys_tables()

Description: Collects statistics about the system catalogs of all the namespaces in pg_catalog and information_schema schemas on each node. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_global_stat_sys_indexes()

Description: Displays index status information about all the system catalogs in the pg_catalog and information_schema schemas on each node. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_summary_stat_sys_indexes()

Description: Collects statistics about index status information about all the system catalogs in the pg_catalog and information_schema schemas on each node. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_global_stat_user_tables()

Description: Displays the status information about customized ordinary tables in all namespaces. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_summary_stat_user_tables()

Description: Collects statistics about the status information about customized ordinary tables in all namespaces. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_global_stat_user_indexes()

Description: Displays the status information about the index of customized ordinary tables in all databases. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_summary_stat_user_indexes()

Description: Collects statistics about the status information about the index of customized ordinary tables in all databases. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_global_stat_database()

Description: Displays database statistics of all nodes. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_global_stat_database_conflicts()

Description: Collects statistics on the database of all nodes. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_global_stat_xact_all_tables()

Description: Displays transaction status information about all ordinary tables and TOAST tables in all namespaces. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_summary_stat_xact_all_tables()

Description: Collects statistics about transaction status information about all ordinary tables and TOAST tables in all namespaces. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_global_stat_xact_sys_tables()

Description: Displays transaction status information about all system catalogs in namespaces on all nodes. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_summary_stat_xact_sys_tables()

Description: Collects statistics about transaction status information about all system catalogs in namespaces on all nodes. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_global_stat_xact_user_tables()

Description: Displays the transaction status information of the user tables in the namespaces on all nodes. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_summary_stat_xact_user_tables()

Description: Collects statistics about the transaction status information of the user tables in the namespaces on all nodes. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_global_stat_user_functions()

Description: Displays the transaction status information of customized functions in the namespaces on all nodes. To query the function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_global_stat_xact_user_functions()

Description: Collects statistics about the transaction status information of customized functions in the namespaces on all nodes. To query the function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_global_stat_bad_block()

Description: Displays information about table and index read failures on all nodes. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_global_file_redo_iostat()

Description: Collects statistics on information about table and index read failures on all nodes. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_global_file_iostat()

Description: Displays statistics about data file I/Os on all nodes. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_global_locks()

Description: Displays lock information of all nodes. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_global_replication_slots()

Description: Displays logical replication information on all nodes. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_global_bgwriter_stat()

Description: Displays statistics about the background writer process's activities on all nodes. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_global_replication_stat()

Description: Displays information about log synchronization status on each node, such as the locations where the sender sends logs and where the receiver receives logs. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_global_transactions_running_xacts()

Description: Displays information about running transactions on each node. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_summary_transactions_running_xacts()

Description: Collects statistics of information about running transactions on each node. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_global_transactions_prepared_xacts()

Description: Displays information about transactions that are currently prepared for two-phase commit on each node. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_summary_transactions_prepared_xacts()

Description: Collects statistics information about transactions that are currently prepared for two-phase commit on each node. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_summary_statement()

Description: Displays the status information of the historically-executed statements on each node. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_global_statement_count()

Description: Displays the number of SELECT, UPDATE, INSERT, and DELETE statements and response time information (TOTAL, AVG, MIN, and MAX) on each node. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_global_config_settings()

Description: Displays GUC parameter configuration information on each node. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_global_wait_events()

Description: Displays the wait event status information on each node. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_statement_responsetime_percentile()

Description: Obtains the response time distribution for 80% and 95% SQL statements of MogDB. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_summary_user_login()

Description: Collects statistics about number of user login and logout times on each node in MogDB. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.get_global_record_reset_time()

Description: Displays the statistics about reset (restart, primary/standby switchover, and database deletion) time of MogDB. To query this function, you must have the sysadmin permission.

Return type: record
gs_wlm_user_resource_info(name text)

Description: Queries for a user's resource quota and resource usage.

Return type: record
pg_stat_get_file_stat()

Description: Rrecords statistics about data file I/Os to indicate I/O performance and detect performance problems such as abnormal I/O operations.

Return type: record
pg_stat_get_redo_stat()

Description: Displays statistics on the replay of session thread logs.

Return type: record
pg_stat_get_status(int8)

Description: Allows you to test the block waiting status about the backend thread and auxiliary thread of the current instance.

Return type: record
get_local_rel_iostat()

Description: Queries the accumulated I/O status of data files on the current node.

Return type: record
DBE_PERF.get_global_rel_iostat()

Description: Displays statistics about data file I/Os on all nodes. To query this function, you must have the sysadmin permission.

Return type: record
DBE_PERF.global_threadpool_status()

Description: Displays the status of worker threads and sessions in thread pools on all nodes. For details about the columns returned by the function, see GLOBAL_THREADPOOL_STATUS.

Return type: record

remote_bgwriter_stat()

Description: Displays the information about pages flushed by the bgwriter threads of all instances in the cluster, number of pages in the candidate buffer chain, and buffer elimination information (except for the local node and not available on the DN).

Return type: record

Table 7 remote_bgwriter_stat parameter description

Parameter	Type	Description
node_name	text	Instance name
bgwr_actual_flush_total_num	bigint	Total number of dirty pages flushed by the bgwriter thread from the startup time to the current time
bgwr_last_flush_num	integer	Number of dirty pages flushed by the bgwriter thread in the previous batch
candidate_slots	integer	Number of pages in the current candidate buffer chain.
get_buffer_from_list	bigint	Number of times that pages are obtained from the candidate buffer chain during buffer elimination.
get_buf_clock_sweep	bigint	Number of times that pages are obtained from the original elimination solution during buffer elimination.

remote_ckpt_stat()

Description: Displays the checkpoint information and log flushing information about all instances in the cluster (except the current node).

Return type: record

Table 8 remote_ckpt_stat parameter description

Parameter	Type	Description
node_name	text	Instance name
ckpt_redo_point	text	Checkpoint of the current instance
ckpt_clog_flush_num	int8	Number of Clog flushing pages from the startup time to the current time
ckpt_csnlog_flush_num	int8	Number of CSN log flushing pages from the startup time to the current time
ckpt_multixact_flush_num	int8	Number of MultiXact flushing pages from the startup time to the current time
ckpt_predicate_flush_num	int8	Number of predicate flushing pages from the startup time to the current time
ckpt_twophase_flush_num	int8	Number of two-phase flushing pages from the startup time to the current time

remote_double_write_stat()

Description: Displays doublewrite file status of all instances in the cluster (except the current node).

Return type: record

Table 9 remote_double_write_stat parameter description

Parameter	Type	Description
node_name	text	Instance name
curr_dwn	int8	Sequence number of the doublewrite file
curr_start_page	int8	Start page for restoring the doublewrite file
file_trunc_num	int8	Number of times that the doublewrite file is reused
file_reset_num	int8	Number of reset times after the doublewrite file is full
total_writes	int8	Total number of I/Os of the doublewrite file
low_threshold_writes	int8	Number of I/Os for writing doublewrite files with low efficiency (the number of I/O flushing pages at a time is less than 16)
high_threshold_writes	int8	Number of I/Os for writing doublewrite files with high efficiency (the number of I/O flushing pages at a time is more than 421)
total_pages	int8	Total number of pages that are flushed to the doublewrite file area
low_threshold_pages	int8	Number of pages that are flushed with low efficiency
high_threshold_pages	int8	Number of pages that are flushed with high efficiency

remote_pagewriter_stat()

Description: Displays the page flushing information and checkpoint information about all instances in the cluster (except the current node).

Return type: record

Table 10 remote_pagewriter_stat parameter description

Parameter	Type	Description
node_name	text	Instance name
pgwr_actual_flush_total_num	int8	Total number of dirty pages flushed from the startup time to the current time
pgwr_last_flush_num	int4	Number of dirty pages flushed in the previous batch
remain_dirty_page_num	int8	Estimated number of dirty pages that are not flushed
queue_head_page_rec_lsn	text	recovery_lsn of the first dirty page in the dirty page queue of the current instance
queue_rec_lsn	text	recovery_lsn of the dirty page queue of the current instance
current_xlog_insert_lsn	text	Write position of Xlogs in the current instance
ckpt_redo_point	text	Checkpoint of the current instance

remote_recovery_status()

Description: Displays log flow control information about the primary and standby nodes (except the current node).

Return type: record

Table 11 remote_recovery_status parameter description

Parameter	Type	Description
node_name	text	Node name (including the primary and standby nodes)
standby_node_name	text	Name of the standby node
source_ip	text	IP address of the primary node
source_port	int4	Port number of the primary node
dest_ip	text	IP address of the standby node
dest_port	int4	Port number of the standby node
current_rto	int8	Current log flow control time of the standby node (unit: s)
target_rto	int8	Expected flow control time of the standby node specified by the corresponding GUC parameter (unit: s)
current_sleep_time	int8	Sleep time required to achieve the expected flow control time (unit: μs)

remote_redo_stat()

Description: Displays the log replay status of all instances in the cluster (except the current node).

Return type: record

Table 12 remote_redo_stat parameter description

Parameter	Type	Description
node_name	text	Instance name
redo_start_ptr	int8	Start point for replaying the instance logs
redo_start_time	int8	Start time (UTC) when the instance logs are replayed
redo_done_time	int8	End time (UTC) when the instance logs are replayed
curr_time	int8	Current time (UTC) of the instance
min_recovery_point	int8	Position of the minimum consistency point for the instance logs
read_ptr	int8	Position for reading the instance logs
last_replayed_read_ptr	int8	Position for replaying the instance logs
recovery_done_ptr	int8	Replay position after the instance is started
read_xlog_io_counter	int8	Number of I/Os when the instance reads and replays logs
read_xlog_io_total_dur	int8	Total I/O latency when the instance reads and replays logs
read_data_io_counter	int8	Number of data page I/O reads during replay in the instance
read_data_io_total_dur	int8	Total I/O latency of data page reads during replay in the instance
write_data_io_counter	int8	Number of data page I/O writes during replay in the instance
write_data_io_total_dur	int8	Total I/O latency of data page writes during replay in the instance
process_pending_counter	int8	Number of synchronization times of log distribution threads during replay in the instance
process_pending_total_dur	int8	Total synchronization latency of log distribution threads during replay in the instance
apply_counter	int8	Number of synchronization times of replay threads during replay in the instance
apply_total_dur	int8	Total synchronization latency of replay threads during replay in the instance
speed	int8	Log replay rate of the current instance
local_max_ptr	int8	Maximum number of replay logs received by the local host after the instance is started
primary_flush_ptr	int8	Log point where the host flushes logs to a disk
worker_info	text	Replay thread information of the instance. If concurrent replay is not enabled, the value is NULL.

Example:

The function pg_backend_pid shows the ID of the current server thread.

mogdb=# SELECT pg_backend_pid();
 pg_backend_pid
-----------------
 139706243217168
(1 row)

The function pg_stat_get_backend_pid shows the ID of a given server thread.

mogdb=# SELECT pg_stat_get_backend_pid(1);
 pg_stat_get_backend_pid
-------------------------
         139706243217168
(1 row)

Issue