diff options
Diffstat (limited to 'src/backend/tcop/postgres.c')
| -rw-r--r-- | src/backend/tcop/postgres.c | 16 |
1 files changed, 14 insertions, 2 deletions
diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c index a3b9757565e..9a948f825df 100644 --- a/src/backend/tcop/postgres.c +++ b/src/backend/tcop/postgres.c @@ -2201,7 +2201,8 @@ check_log_statement(List *stmt_list) /* * check_log_duration - * Determine whether current command's duration should be logged + * Determine whether current command's duration should be logged. + * If log_statement_sample_rate < 1.0, log only a sample. * * Returns: * 0 if no logging is needed @@ -2223,6 +2224,7 @@ check_log_duration(char *msec_str, bool was_logged) int usecs; int msecs; bool exceeded; + bool in_sample; TimestampDifference(GetCurrentStatementStartTimestamp(), GetCurrentTimestamp(), @@ -2239,7 +2241,17 @@ check_log_duration(char *msec_str, bool was_logged) (secs > log_min_duration_statement / 1000 || secs * 1000 + msecs >= log_min_duration_statement))); - if (exceeded || log_duration) + /* + * Do not log if log_statement_sample_rate = 0. Log a sample if + * log_statement_sample_rate <= 1 and avoid unecessary random() call + * if log_statement_sample_rate = 1. + */ + if (exceeded) + in_sample = log_statement_sample_rate != 0 && + (log_statement_sample_rate == 1 || + random() <= log_statement_sample_rate * MAX_RANDOM_VALUE); + + if ((exceeded && in_sample) || log_duration) { snprintf(msec_str, 32, "%ld.%03d", secs * 1000 + msecs, usecs % 1000); |