PGXC_WLM_SESSION_STATISTICS

PGXC_WLM_SESSION_STATISTICS displays load management information about jobs that are being executed on CNs.

**Table 1** PGXC_WLM_SESSION_STATISTICS columns
Name	Type	Description
datid	oid	OID of the database this backend is connected to
dbname	name	Name of the database the backend is connected to
schemaname	text	Schema name
nodename	text	Name of the CN where the statement is executed
username	name	User name used for connecting to the backend
application_name	text	Name of the application that is connected to the backend
client_addr	inet	IP address of the client connected to this backend. If this column is null, it indicates either that the client is connected via a Unix socket on the server machine or that 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 only be non-null for IP connections, and only when log_hostname is enabled.
client_port	integer	TCP port number used by the client to communicate with the backend. If a Unix socket is used, it is –1.
query_band	text	Job type, which is specified by the GUC parameter query_band parameter. The default value is a null string.
pid	bigint	ID of the backend thread
block_time	bigint	Block time before the statement is executed. The unit is ms.
start_time	timestamp with time zone	Time when the statement starts to be executed
duration	bigint	For how long a statement has been executing. The unit is ms.
estimate_total_time	bigint	Estimated execution time of a statement. The unit is ms.
estimate_left_time	bigint	Estimated remaining time of statement execution. The unit is ms.
enqueue	text	Workload management resource status
resource_pool	name	Resource pool used by the user
control_group	text	Cgroup used by the statement
estimate_memory	integer	Estimated memory used by a statement on a single instance. The unit is MB. This column takes effect only when the GUC parameter enable_dynamic_workload is set to on.
min_peak_memory	integer	Minimum memory peak of a statement across all DNs. The unit is MB.
max_peak_memory	integer	Maximum memory peak of a statement across all DNs. The unit is MB.
average_peak_memory	integer	Average memory usage during statement execution. The unit is MB.
memory_skew_percent	integer	Memory usage skew of a statement among DNs.
spill_info	text	Spill information for the statement on all DNs. The options are: None: The statement has not been spilled to disks on any DNs. All: The statement has been spilled to disks on all DNs. [a:b]: The statement has been spilled to disks on a of b DNs.
min_spill_size	integer	Minimum spilled data among all DNs when a spill occurs. The unit is MB. The default value is 0.
max_spill_size	integer	Maximum spilled data among all DNs when a spill occurs. The unit is MB. The default value is 0.
average_spill_size	integer	Average spilled data among all DNs when a spill occurs. The unit is MB. The default value is 0.
spill_skew_percent	integer	DN spill skew when a spill occurs
min_dn_time	bigint	Minimum execution time of a statement across all DNs. The unit is ms.
max_dn_time	bigint	Maximum execution time of a statement across all DNs. The unit is ms.
average_dn_time	bigint	Average execution time of a statement across all DNs. The unit is ms.
dntime_skew_percent	integer	Execution time skew of a statement among DNs.
min_cpu_time	bigint	Minimum CPU time of a statement across all DNs. The unit is ms.
max_cpu_time	bigint	Maximum CPU time of a statement across all DNs. The unit is ms.
total_cpu_time	bigint	Total CPU time of a statement across all DNs. The unit is ms.
cpu_skew_percent	integer	CPU time skew of a statement among DNs.
min_peak_iops	integer	Minimum IOPS peak of a statement across all DNs. It is counted by ones in a column-store table and by ten thousands in a row-store table.
max_peak_iops	integer	Maximum IOPS peak of a statement across all DNs. It is counted by ones in a column-store table and by ten thousands in a row-store table.
average_peak_iops	integer	Average IOPS peak of a statement across all DNs. It is counted by ones in a column-store table and by ten thousands in a row-store table.
iops_skew_percent	integer	I/O skew across DNs.
min_read_speed	integer	Minimum I/O read rate of a statement across all DNs within a monitoring period (5s). The unit is KB/s.
max_read_speed	integer	Maximum I/O read rate of a statement across all DNs within a monitoring period (5s). The unit is KB/s.
average_read_speed	integer	Average I/O read rate of a statement across all DNs within a monitoring period (5s). The unit is KB/s.
min_write_speed	integer	Minimum I/O write rate of a statement across all DNs within a monitoring period (5s). The unit is KB/s.
max_write_speed	integer	Maximum I/O write rate of a statement across all DNs within a monitoring period (5s). The unit is KB/s.
average_write_speed	integer	Average I/O write rate of a statement across all DNs within a monitoring period (5s). The unit is KB/s.
recv_pkg	bigint	Total number of communication packages received by a statement across all DNs.
send_pkg	bigint	Total number of communication packages sent by a statement across all DNs.
recv_bytes	bigint	Total received data of the statement stream, in byte.
send_bytes	bigint	Total sent data of the statement stream, in byte.
warning	text	Warning. The following warnings and warnings related to SQL self-diagnosis tuning are displayed: Spill file size large than 256MB Broadcast size large than 100MB Early spill Spill times is greater than 3 Spill on memory adaptive Hash table conflict
unique_sql_id	bigint	ID of the normalized unique SQL.
queryid	bigint	Internal query ID used for statement execution
query	text	Statement that is being executed
query_plan	text	Execution plan of a statement Specification restrictions: Execution plans are displayed only for DML statements. In 8.2.1.100 and later versions, the number of data binding times is added to the execution plans of Parse Bind Execute (PBE) statements to facilitate statement analysis. The number of data binding times is displayed in the format of PBE bind times: Times.
node_group	text	Logical cluster of the user running the statement
stmt_type	text	Query type corresponding to the statement.
except_info	text	Information about the exception rule triggered by the statement.
parse_time	bigint	Total parsing time before the statement is queued (including lexical and syntax parsing, optimization rewriting, and plan generation time), in milliseconds. This column is only supported in version 8.3.0.100 or later.
disk_cache_hit_ratio	numeric(5,2)	Disk cache hit rate. This column only applies to OBS 3.0 tables and foreign tables in decoupled storage and compute scenarios.
disk_cache_disk_read_size	bigint	Total size of data read from disk cache, in MB. This column only applies to OBS 3.0 tables and foreign tables in decoupled storage and compute scenarios.
disk_cache_disk_write_size	bigint	Total size of data written to disk cache, in MB. This column only applies to OBS 3.0 tables and foreign tables in decoupled storage and compute scenarios.
disk_cache_remote_read_size	bigint	Total size of data read remotely from OBS due to disk cache read failure, in MB. This column only applies to OBS 3.0 tables and foreign tables in decoupled storage and compute scenarios.
disk_cache_remote_read_time	bigint	Total number of times data is read remotely from OBS due to disk cache read failure. This column only applies to OBS 3.0 tables and foreign tables in decoupled storage and compute scenarios.