Updated on 2024-11-05 GMT+08:00

PGXC_WLM_SESSION_INFO

PGXC_WLM_SESSION_INFO displays load management information for completed jobs executed on all CNs. The data in this view is obtained from GS_WLM_SESSION_INFO.

The columns are similar to those in the GS_WLM_SESSION_HISTORY view. For details, see Table 1.

Table 1 GS_WLM_SESSION_HISTORY columns

Name

Type

Description

datid

oid

OID of the database connected to the backend.

dbname

text

Name of the database connected to the backend.

schemaname

text

Schema name.

nodename

text

Name of the CN where the statement is run.

username

text

Username used for connecting to the backend.

application_name

text

Name of the application connected to the backend.

client_addr

inet

IP address of the client connected to the 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 can be set through the GUC parameter query_band and is null string by default.

block_time

bigint

Blocking time before statement execution, including statement parsing and optimization time, in milliseconds.

start_time

timestamp with time zone

Start time of statement execution.

finish_time

timestamp with time zone

End time of statement execution.

duration

bigint

Execution time of a statement. The unit is ms.

estimate_total_time

bigint

Estimated execution time of a statement. The unit is ms.

status

text

End status of statement execution: finished for normal and aborted for abnormal. The statement status recorded here should be the database server execution status. When the server-side execution is successful and an error occurs when the result set is returned, the statement should be finished.

abort_info

text

Exception information displayed if the final statement execution status is aborted.

resource_pool

text

Resource pool used by the user.

control_group

text

Cgroup used by the statement.

estimate_memory

integer

Estimated memory used by the statement. The unit is MB.

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

Statement spill information on all DNs.

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 default value is 0. The unit is MB.

max_spill_size

integer

Maximum spilled data among all DNs when a spill occurs. The default value is 0. The unit is MB.

average_spill_size

integer

Average spilled data among all DNs when a spill occurs. The default value is 0. The unit is MB.

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 I/O peak of a statement on all DNs (times/s in column-store tables and 10,000 times/s in row-store tables). This function is not enabled in clusters of version 8.1.3. Therefore, you are not advised to refer to this column to analyze memory problems.

max_peak_iops

integer

Maximum I/O peak of a statement on all DNs (times/s in column-store tables and 10,000 times/s in row-store tables). This function is not enabled in clusters of version 8.1.3. Therefore, you are not advised to refer to this column to analyze memory problems.

average_peak_iops

integer

Average I/O peak of a statement on all DNs (times/s in column-store tables and 10,000 times/s in row-store tables). This function is not enabled in clusters of version 8.1.3. Therefore, you are not advised to refer to this column to analyze memory problems.

iops_skew_percent

integer

I/O skew of a statement among DNs. This function is not enabled in clusters of version 8.1.3. You are not advised to refer to this column to analyze memory problems.

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

queryid

bigint

Internal query ID used for statement execution.

query

text

Executed statement.

query_plan

text

Execution plan of a statement.

node_group

text

Logical cluster of the user running the statement.

pid

bigint

PID of the backend thread for the statement.

lane

text

Fast/Slow lane where the statement is executed.

unique_sql_id

bigint

ID of the normalized unique SQL.