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  5. GS_WLM_SESSION_HISTORY

GS_WLM_SESSION_HISTORY

GS_WLM_SESSION_HISTORY displays load management information about a completed job executed by the current user on the current CN. This view is used by Database Manager to query data from DWS. Data in DWS is cleared every 3 minutes.

Table 1 GS_WLM_SESSION_HISTORY columns

Name

Type

Description

datid

oid

OID of the database this backend is connected to

dbname

text

Name of the database the backend is connected to

schemaname

text

Schema name

nodename

text

Name of the CN where the statement is run

username

text

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 that the client uses for communication with this backend, or -1 if a Unix socket is used

query_band

text

Job type, which is specified by the query_band parameter. The default value is a null string.

block_time

bigint

Duration that a statement is blocked before being executed, including the statement parsing and optimization duration. The unit is ms.

start_time

timestamp with time zone

Time when the statement starts to be run

finish_time

timestamp with time zone

Time when the statement execution ends

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

Final statement execution status. Its value can be finished (normal) or aborted (abnormal).

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

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 indicates that the statement has not been issued to any DNs.

All indicates that the statement has been flushed to disks on every DN.

[a:b] indicates that the statement has been flushed 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.

warning

text

Warning. The following warnings and warnings related to SQL Self-Diagnosis Optimization are displayed:

  1. Spill file size large than 256MB
  2. Broadcast size large than 100MB
  3. Early spill
  4. Spill times is greater than 3
  5. Spill on memory adaptive
  6. Hash table conflict

queryid

integer

Internal query ID used for statement execution

query

text

Statement executed

query_plan

text

Execution plan of a statement