postgres.git / summary / log / commit / refs

commit    d8453ccfbfd6bb1782e71beb28acf4025a9a01ce
Author:   Tomas Vondra <tomas.vondra@postgresql.org>
Date:     Sun Aug 04 18:19:54 2019 +0000
First released in: 13.0, 12.0

    Revert "Silence compiler warning"
    
    This reverts commit 9dc122585551516309c9362e673effdbf3bd79bd.
    
    As committed, statement sampling used the existing duration threshold
    (log_min_duration_statement) when decide which statements to sample.
    The issue is that even the longest statements are subject to sampling,
    and so may not end up logged. An improvement was proposed, introducing
    a second duration threshold, but it would not be backwards compatible.
    So we've decided to revert this feature - the separate threshold should
    be part of the feature itself.
    
    Discussion: https://postgr.es/m/CAFj8pRDS8tQ3Wviw9%3DAvODyUciPSrGeMhJi_WPE%2BEB8%2B4gLL-Q%40mail.gmail.com


 src/backend/tcop/postgres.c | 13 ++++++-------
 1 file changed, 6 insertions(+), 7 deletions(-)

diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
index 44a59e1d4fb..f010aa884ce 100644
--- a/src/backend/tcop/postgres.c
+++ b/src/backend/tcop/postgres.c
@@ -2236,14 +2236,13 @@ check_log_duration(char *msec_str, bool was_logged)
 
 		/*
 		 * Do not log if log_statement_sample_rate = 0. Log a sample if
-		 * log_statement_sample_rate <= 1 and avoid unnecessary random() call
-		 * if log_statement_sample_rate = 1.  But don't compute any of this
-		 * unless needed.
+		 * log_statement_sample_rate <= 1 and avoid unecessary random() call
+		 * if log_statement_sample_rate = 1.
 		 */
-		in_sample = exceeded &&
-			log_statement_sample_rate != 0 &&
-			(log_statement_sample_rate == 1 ||
-			 random() <= log_statement_sample_rate * MAX_RANDOM_VALUE);
+		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 || xact_is_sampled)
 		{


[parent: df521ab79547]