log_statement_stats

A configuration parameter determining whether to log statement performance statistics

log_statement_stats is a configuration parameter determining whether to log detailed performance statistics for statement execution.

log_statement_stats was added in PostgreSQL 7.4.

Usage

If log_statement_stats is set to "on", a DETAIL line will be emitted containing details about the statement execution, including execution time and memory / i/o usage.

log_statement_stats cannot be enabled at the same time as one or more of log_executor_stats, log_parser_stats, or log_planner_stats.

Default value

The default value for log_statement_stats is: off.

Change history

Examples

Log output from issuing a simple statement ("SELECT 1"):

[2021-03-29 17:23:14 UTC] psql postgres postgres STATEMENT:  SELECT 1;
[2021-03-29 17:23:14 UTC] psql postgres postgres LOG:  00000: QUERY STATISTICS
[2021-03-29 17:23:14 UTC] psql postgres postgres DETAIL:  ! system usage stats:
        !       0.000330 s user, 0.000000 s system, 0.000333 s elapsed
        !       [0.002029 s user, 0.000000 s system total]
        !       10956 kB max resident size
        !       0/0 [0/0] filesystem blocks in/out
        !       0/22 [0/461] page faults/reclaims, 0 [0] swaps
        !       0 [0] signals rcvd, 0/0 [0/0] messages rcvd/sent
        !       0/0 [3/0] voluntary/involuntary context switches

It is not possible to enable log_executor_stats, log_parser_stats, or log_planner_stats:

[2021-03-29 17:46:23 UTC]    LOG:  22023: invalid value for parameter "log_executor_stats": 1
[2021-03-29 17:46:23 UTC]    DETAIL:  Cannot enable parameter when "log_statement_stats" is true.

Categories

GUC configuration item, Logging

See also

log_executor_stats, log_parser_stats, log_planner_stats