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[PATCH v3 1/3] Move TAP log-searching feature to common modules
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* [PATCH v3 1/3] Move TAP log-searching feature to common modules
@ 2021-01-05 04:34  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 9+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-05 04:34 UTC (permalink / raw)

Some private functions in 019_repslot_limit.pl will be used in other
tests. Move them to common modules so that they are available to the
new tests.
---
 src/test/perl/PostgresNode.pm             | 33 ++++++++++++++++++++
 src/test/perl/TestLib.pm                  | 16 +++++++---
 src/test/recovery/t/019_replslot_limit.pl | 37 ++++-------------------
 3 files changed, 51 insertions(+), 35 deletions(-)

diff --git a/src/test/perl/PostgresNode.pm b/src/test/perl/PostgresNode.pm
index 9667f7667e..b09273efe5 100644
--- a/src/test/perl/PostgresNode.pm
+++ b/src/test/perl/PostgresNode.pm
@@ -2223,6 +2223,39 @@ sub pg_recvlogical_upto
 
 =pod
 
+=item $node->current_log_position()
+
+Return the current position of server log.
+
+=cut
+
+sub current_log_position
+{
+	my $self = shift;
+
+	return (stat $self->logfile)[7];
+}
+
+=pod
+
+=item $node->find_in_log($pattern, $startpos)
+
+Returns whether the $pattern occurs after $startpos in the server log.
+
+=cut
+
+sub find_in_log
+{
+	my ($self, $pattern, $startpos) = @_;
+
+	$startpos = 0 unless defined $startpos;
+	my $log = TestLib::slurp_file($self->logfile, $startpos);
+
+	return $log =~ m/$pattern/;
+}
+
+=pod
+
 =back
 
 =cut
diff --git a/src/test/perl/TestLib.pm b/src/test/perl/TestLib.pm
index 1baf6bd001..8751f48dfe 100644
--- a/src/test/perl/TestLib.pm
+++ b/src/test/perl/TestLib.pm
@@ -430,30 +430,38 @@ sub slurp_dir
 
 =pod
 
-=item slurp_file(filename)
+=item slurp_file(filename, pos)
 
-Return the full contents of the specified file.
+Return the contents after pos of the specified file.
+Reutrns the full contents if pos is omitted.
 
 =cut
 
 sub slurp_file
 {
-	my ($filename) = @_;
+	my ($filename, $from) = @_;
 	local $/;
 	my $contents;
+
+	$from = 0 unless defined $from;
+
 	if ($Config{osname} ne 'MSWin32')
 	{
 		open(my $in, '<', $filename)
 		  or croak "could not read \"$filename\": $!";
+		seek($in, $from, 0)
+		  or croak "could not seek \"$filename\" to $from: $!";
 		$contents = <$in>;
 		close $in;
 	}
 	else
 	{
 		my $fHandle = createFile($filename, "r", "rwd")
-		  or croak "could not open \"$filename\": $^E";
+		  or croak "could not open \"$filename\": $^E\n";
 		OsFHandleOpen(my $fh = IO::Handle->new(), $fHandle, 'r')
 		  or croak "could not read \"$filename\": $^E\n";
+		seek($fh, $from, 0)
+		  or croak "could not seek \"$filename\" to $from: $^E\n";
 		$contents = <$fh>;
 		CloseHandle($fHandle)
 		  or croak "could not close \"$filename\": $^E\n";
diff --git a/src/test/recovery/t/019_replslot_limit.pl b/src/test/recovery/t/019_replslot_limit.pl
index 20f4a1bbc3..b298d9992f 100644
--- a/src/test/recovery/t/019_replslot_limit.pl
+++ b/src/test/recovery/t/019_replslot_limit.pl
@@ -165,19 +165,17 @@ $node_primary->wait_for_catchup($node_standby, 'replay', $start_lsn);
 
 $node_standby->stop;
 
-ok( !find_in_log(
-		$node_standby,
-		"requested WAL segment [0-9A-F]+ has already been removed"),
+ok( !$node_standby->find_in_log(
+		 "requested WAL segment [0-9A-F]+ has already been removed"),
 	'check that required WAL segments are still available');
 
 # Advance WAL again, the slot loses the oldest segment.
-my $logstart = get_log_size($node_primary);
+my $logstart = $node_primary->current_log_position();
 advance_wal($node_primary, 7);
 $node_primary->safe_psql('postgres', "CHECKPOINT;");
 
 # WARNING should be issued
-ok( find_in_log(
-		$node_primary,
+ok( $node_primary->find_in_log(
 		"invalidating slot \"rep1\" because its restart_lsn [0-9A-F/]+ exceeds max_slot_wal_keep_size",
 		$logstart),
 	'check that the warning is logged');
@@ -190,14 +188,13 @@ is($result, "rep1|f|t|lost|",
 	'check that the slot became inactive and the state "lost" persists');
 
 # The standby no longer can connect to the primary
-$logstart = get_log_size($node_standby);
+$logstart = $node_standby->current_log_position();
 $node_standby->start;
 
 my $failed = 0;
 for (my $i = 0; $i < 10000; $i++)
 {
-	if (find_in_log(
-			$node_standby,
+	if ($node_standby->find_in_log(
 			"requested WAL segment [0-9A-F]+ has already been removed",
 			$logstart))
 	{
@@ -264,25 +261,3 @@ sub advance_wal
 	}
 	return;
 }
-
-# return the size of logfile of $node in bytes
-sub get_log_size
-{
-	my ($node) = @_;
-
-	return (stat $node->logfile)[7];
-}
-
-# find $pat in logfile of $node after $off-th byte
-sub find_in_log
-{
-	my ($node, $pat, $off) = @_;
-
-	$off = 0 unless defined $off;
-	my $log = TestLib::slurp_file($node->logfile);
-	return 0 if (length($log) <= $off);
-
-	$log = substr($log, $off);
-
-	return $log =~ m/$pat/;
-}
-- 
2.27.0


----Next_Part(Tue_Jan__5_17_26_02_2021_224)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v3-0002-New-test-for-timeline-tracking-of-walsender.patch"



^ permalink  raw  reply  [nested|flat] 9+ messages in thread

* [PATCH v16 3/4] Merge constants in ArrayExpr into groups
@ 2023-10-15 08:06  Dmitrii Dolgov <[email protected]>
  0 siblings, 0 replies; 9+ messages in thread

From: Dmitrii Dolgov @ 2023-10-15 08:06 UTC (permalink / raw)

Using query_id_const_merge only first/last element in an ArrayExpr will
be used to compute query id. Extend this to take into account number of
elements, and merge constants into groups based on it. Resulting groups
are powers of 10, i.e. 1 to 9, 10 to 99, etc.
---
 .../pg_stat_statements/expected/merging.out   | 84 +++++++++++++++----
 .../pg_stat_statements/pg_stat_statements.c   | 17 +++-
 contrib/pg_stat_statements/sql/merging.sql    | 13 +++
 doc/src/sgml/pgstatstatements.sgml            | 11 +--
 src/backend/nodes/queryjumblefuncs.c          | 52 ++++++++----
 src/include/nodes/queryjumble.h               |  7 +-
 6 files changed, 142 insertions(+), 42 deletions(-)

diff --git a/contrib/pg_stat_statements/expected/merging.out b/contrib/pg_stat_statements/expected/merging.out
index f286c735a36..7400870f3f6 100644
--- a/contrib/pg_stat_statements/expected/merging.out
+++ b/contrib/pg_stat_statements/expected/merging.out
@@ -54,11 +54,11 @@ SELECT * FROM test_merge WHERE id IN (1, 2, 3);
 (0 rows)
 
 SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
-                   query                    | calls 
---------------------------------------------+-------
- SELECT * FROM test_merge WHERE id IN ($1)  |     1
- SELECT * FROM test_merge WHERE id IN (...) |     1
- SELECT pg_stat_statements_reset()          |     1
+                          query                           | calls 
+----------------------------------------------------------+-------
+ SELECT * FROM test_merge WHERE id IN ($1)                |     1
+ SELECT * FROM test_merge WHERE id IN (... [1-9 entries]) |     1
+ SELECT pg_stat_statements_reset()                        |     1
 (3 rows)
 
 SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9);
@@ -80,7 +80,60 @@ SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
                                  query                                  | calls 
 ------------------------------------------------------------------------+-------
  SELECT * FROM test_merge WHERE id IN ($1)                              |     1
- SELECT * FROM test_merge WHERE id IN (...)                             |     4
+ SELECT * FROM test_merge WHERE id IN (... [1-9 entries])               |     2
+ SELECT * FROM test_merge WHERE id IN (... [10-99 entries])             |     2
+ SELECT pg_stat_statements_reset()                                      |     1
+ SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C" |     1
+(5 rows)
+
+-- Second order of magnitude, brace yourself
+SELECT pg_stat_statements_reset();
+ pg_stat_statements_reset 
+--------------------------
+ 
+(1 row)
+
+SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110);
+ id | data 
+----+------
+(0 rows)
+
+SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
+                            query                             | calls 
+--------------------------------------------------------------+-------
+ SELECT * FROM test_merge WHERE id IN (... [100-999 entries]) |     1
+ SELECT pg_stat_statements_reset()                            |     1
+(2 rows)
+
+-- With gaps on the threshold
+SELECT pg_stat_statements_reset();
+ pg_stat_statements_reset 
+--------------------------
+ 
+(1 row)
+
+SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4);
+ id | data 
+----+------
+(0 rows)
+
+SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
+                          query                           | calls 
+----------------------------------------------------------+-------
+ SELECT * FROM test_merge WHERE id IN (... [1-9 entries]) |     1
+ SELECT pg_stat_statements_reset()                        |     1
+(2 rows)
+
+SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15);
+ id | data 
+----+------
+(0 rows)
+
+SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
+                                 query                                  | calls 
+------------------------------------------------------------------------+-------
+ SELECT * FROM test_merge WHERE id IN (... [1-9 entries])               |     1
+ SELECT * FROM test_merge WHERE id IN (... [10-99 entries])             |     1
  SELECT pg_stat_statements_reset()                                      |     1
  SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C" |     1
 (4 rows)
@@ -108,11 +161,12 @@ SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11) and dat
 (0 rows)
 
 SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
-                          query                           | calls 
-----------------------------------------------------------+-------
- SELECT * FROM test_merge WHERE id IN (...) and data = $3 |     3
- SELECT pg_stat_statements_reset()                        |     1
-(2 rows)
+                                  query                                   | calls 
+--------------------------------------------------------------------------+-------
+ SELECT * FROM test_merge WHERE id IN (... [1-9 entries]) and data = $3   |     1
+ SELECT * FROM test_merge WHERE id IN (... [10-99 entries]) and data = $3 |     2
+ SELECT pg_stat_statements_reset()                                        |     1
+(3 rows)
 
 -- No constants simplification
 SELECT pg_stat_statements_reset();
@@ -147,10 +201,10 @@ SELECT * FROM test_merge_numeric WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
 (0 rows)
 
 SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
-                       query                        | calls 
-----------------------------------------------------+-------
- SELECT * FROM test_merge_numeric WHERE id IN (...) |     1
- SELECT pg_stat_statements_reset()                  |     1
+                               query                                | calls 
+--------------------------------------------------------------------+-------
+ SELECT * FROM test_merge_numeric WHERE id IN (... [10-99 entries]) |     1
+ SELECT pg_stat_statements_reset()                                  |     1
 (2 rows)
 
 -- Test constants evaluation, verifies a tricky part to make sure there are no
diff --git a/contrib/pg_stat_statements/pg_stat_statements.c b/contrib/pg_stat_statements/pg_stat_statements.c
index 4d47a746670..a5702c3d749 100644
--- a/contrib/pg_stat_statements/pg_stat_statements.c
+++ b/contrib/pg_stat_statements/pg_stat_statements.c
@@ -2714,6 +2714,8 @@ generate_normalized_query(JumbleState *jstate, const char *query,
 				last_tok_len = 0;	/* Length (in bytes) of that tok */
 	bool		skip = false; 	/* Signals that certain constants are
 								   merged together and have to be skipped */
+	int 		magnitude; 		/* Order of magnitute for number of merged
+								   constants */
 
 
 	/*
@@ -2754,7 +2756,8 @@ generate_normalized_query(JumbleState *jstate, const char *query,
 		Assert(len_to_wrt >= 0);
 
 		/* Normal path, non merged constant */
-		if (!jstate->clocations[i].merged)
+		magnitude = jstate->clocations[i].magnitude;
+		if (magnitude == 0)
 		{
 			memcpy(norm_query + n_quer_loc, query + quer_loc, len_to_wrt);
 			n_quer_loc += len_to_wrt;
@@ -2770,12 +2773,22 @@ generate_normalized_query(JumbleState *jstate, const char *query,
 		/* The firsts merged constant */
 		else if (!skip)
 		{
+			static const uint32 powers_of_ten[] = {
+				1, 10, 100,
+				1000, 10000, 100000,
+				1000000, 10000000, 100000000,
+				1000000000
+			};
+			int lower_merged = powers_of_ten[magnitude - 1];
+			int upper_merged = powers_of_ten[magnitude];
+
 			memcpy(norm_query + n_quer_loc, query + quer_loc, len_to_wrt);
 			n_quer_loc += len_to_wrt;
 
 			/* Skip the following until a non merged constant appear */
 			skip = true;
-			n_quer_loc += sprintf(norm_query + n_quer_loc, "...");
+			n_quer_loc += sprintf(norm_query + n_quer_loc, "... [%d-%d entries]",
+								  lower_merged, upper_merged - 1);
 		}
 		/* Otherwise the constant is merged away */
 
diff --git a/contrib/pg_stat_statements/sql/merging.sql b/contrib/pg_stat_statements/sql/merging.sql
index 8b589135daa..c515e48d50c 100644
--- a/contrib/pg_stat_statements/sql/merging.sql
+++ b/contrib/pg_stat_statements/sql/merging.sql
@@ -27,6 +27,19 @@ SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10);
 SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11);
 SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
 
+-- Second order of magnitude, brace yourself
+SELECT pg_stat_statements_reset();
+SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110);
+SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
+
+-- With gaps on the threshold
+SELECT pg_stat_statements_reset();
+SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4);
+SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
+
+SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15);
+SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
+
 -- More conditions in the query
 SELECT pg_stat_statements_reset();
 
diff --git a/doc/src/sgml/pgstatstatements.sgml b/doc/src/sgml/pgstatstatements.sgml
index bba8e5e11ed..a919696abc2 100644
--- a/doc/src/sgml/pgstatstatements.sgml
+++ b/doc/src/sgml/pgstatstatements.sgml
@@ -559,7 +559,7 @@
 =# SELECT * FROM test WHERE a IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12);
 =# SELECT query, calls FROM pg_stat_statements;
 -[ RECORD 1 ]------------------------------
-query | SELECT * FROM test WHERE a IN (...)
+query | SELECT * FROM test WHERE a IN (... [10-99 entries])
 calls | 2
 -[ RECORD 2 ]------------------------------
 query | SELECT pg_stat_statements_reset()
@@ -896,10 +896,11 @@ calls | 1
       with an array of different lenght.
 
       If this parameter is on, an array of constants will contribute only the
-      first and the last elements to the query identifier. It means two
-      occurences of the same query, where the only difference is number of
-      constants in the array, are going to get the same query identifier.
-      Such queries are represented in form <literal>'(...)'</literal>.
+      first element, the last element and the number of elements to the query
+      identifier. It means two occurences of the same query, where the only
+      difference is number of constants in the array, are going to get the
+      same query identifier if the arrays are of similar length.
+      Such queries are represented in form <literal>'(... [10-99 entries])'</literal>.
 
       The parameter could be used to reduce amount of repeating data stored
       via <structname>pg_stat_statements</structname>.  The default value is off.
diff --git a/src/backend/nodes/queryjumblefuncs.c b/src/backend/nodes/queryjumblefuncs.c
index 4bc16dde6a0..a1d4567ca66 100644
--- a/src/backend/nodes/queryjumblefuncs.c
+++ b/src/backend/nodes/queryjumblefuncs.c
@@ -37,6 +37,8 @@
 #include "nodes/queryjumble.h"
 #include "parser/scansup.h"
 
+#include "utils/numutils.h"
+
 #define JUMBLE_SIZE				1024	/* query serialization buffer size */
 
 /* GUC parameters */
@@ -51,7 +53,7 @@ bool		query_id_enabled = false;
 static void AppendJumble(JumbleState *jstate,
 						 const unsigned char *item, Size size);
 static void RecordConstLocation(JumbleState *jstate,
-								int location, bool merged);
+								int location, int magnitude);
 static void _jumbleNode(JumbleState *jstate, Node *node);
 static void _jumbleElements(JumbleState *jstate, List *elements);
 static void _jumbleA_Const(JumbleState *jstate, Node *node);
@@ -206,12 +208,15 @@ AppendJumble(JumbleState *jstate, const unsigned char *item, Size size)
  * Record location of constant within query string of query tree that is
  * currently being walked.
  *
- * Merged argument signals that the constant represents the first or the last
- * element in a series of merged constants, and everything but the first/last
- * element contributes nothing to the jumble hash.
+ * Magnitude argument larger than zero signals that the constant represents the
+ * first or the last element in a series of merged constants, and everything
+ * but such first/last element will contribute nothing to the jumble hash. The
+ * magnitute value specifies order of magnitute (i.e. how many digits it has)
+ * for the number of elements in the series, to represent the fact of merging
+ * later on.
  */
 static void
-RecordConstLocation(JumbleState *jstate, int location, bool merged)
+RecordConstLocation(JumbleState *jstate, int location, int magnitude)
 {
 	/* -1 indicates unknown or undefined location */
 	if (location >= 0)
@@ -227,7 +232,7 @@ RecordConstLocation(JumbleState *jstate, int location, bool merged)
 		}
 		jstate->clocations[jstate->clocations_count].location = location;
 		/* initialize lengths to -1 to simplify third-party module usage */
-		jstate->clocations[jstate->clocations_count].merged = merged;
+		jstate->clocations[jstate->clocations_count].magnitude = magnitude;
 		jstate->clocations[jstate->clocations_count].length = -1;
 		jstate->clocations_count++;
 	}
@@ -237,24 +242,26 @@ RecordConstLocation(JumbleState *jstate, int location, bool merged)
  * Verify if the provided list contains could be merged down, which means it
  * contains only constant expressions.
  *
- * Return value indicates if merging is possible.
+ * Return value is the order of magnitude (i.e. how many digits it has) for
+ * length of the list (to use for representation purposes later on) if merging
+ * is possible, otherwise zero.
  *
  * Note that this function searches only for explicit Const nodes and does not
  * try to simplify expressions.
  */
-static bool
+static int
 IsMergeableConstList(List *elements, Const **firstConst, Const **lastConst)
 {
 	ListCell   *temp;
 	Node	   *firstExpr = NULL;
 
 	if (elements == NULL)
-		return false;
+		return 0;
 
 	if (!query_id_const_merge)
 	{
 		/* Merging is disabled, process everything one by one */
-		return false;
+		return 0;
 	}
 
 	firstExpr = linitial(elements);
@@ -268,26 +275,26 @@ IsMergeableConstList(List *elements, Const **firstConst, Const **lastConst)
 	{
 		foreach(temp, elements)
 			if (!IsA(lfirst(temp), Const))
-				return false;
+				return 0;
 
 		*firstConst = (Const *) firstExpr;
 		*lastConst = llast_node(Const, elements);
-		return true;
+		return decimalLength32(elements->length);
 	}
 
 	/*
 	 * If we end up here, it means no constants merging is possible, process
 	 * the list as usual.
 	 */
-	return false;
+	return 0;
 }
 
 #define JUMBLE_NODE(item) \
 	_jumbleNode(jstate, (Node *) expr->item)
 #define JUMBLE_ELEMENTS(list) \
 	_jumbleElements(jstate, (List *) expr->list)
-#define JUMBLE_LOCATION(location, merged) \
-	RecordConstLocation(jstate, expr->location, merged)
+#define JUMBLE_LOCATION(location, magnitude) \
+	RecordConstLocation(jstate, expr->location, magnitude)
 #define JUMBLE_FIELD(item) \
 	AppendJumble(jstate, (const unsigned char *) &(expr->item), sizeof(expr->item))
 #define JUMBLE_FIELD_SINGLE(item) \
@@ -304,10 +311,19 @@ static void
 _jumbleElements(JumbleState *jstate, List *elements)
 {
 	Const *first, *last;
-	if(IsMergeableConstList(elements, &first, &last))
+	int magnitude = IsMergeableConstList(elements, &first, &last);
+
+	if (magnitude)
 	{
-		RecordConstLocation(jstate, first->location, true);
-		RecordConstLocation(jstate, last->location, true);
+		RecordConstLocation(jstate, first->location, magnitude);
+		RecordConstLocation(jstate, last->location, magnitude);
+
+		/*
+		 * After merging constants down we end up with only two constants, the
+		 * first and the last one. To distinguish the order of magnitute behind
+		 * merged constants, add its value into the jumble.
+		 */
+		JUMBLE_FIELD_SINGLE(magnitude);
 	}
 	else
 	{
diff --git a/src/include/nodes/queryjumble.h b/src/include/nodes/queryjumble.h
index c64a007ad3f..8ee2e9afbb6 100644
--- a/src/include/nodes/queryjumble.h
+++ b/src/include/nodes/queryjumble.h
@@ -26,9 +26,12 @@ typedef struct LocationLen
 
 	/*
 	 * Indicates the constant represents the beginning or the end of a merged
-	 * constants interval.
+	 * constants interval. The value shows how many constants were merged away
+	 * (up to a power of 10), or in other words the order of manitude for
+	 * number of merged constants (i.e. how many digits it has). Otherwise the
+	 * value is 0, indicating that no merging was performed.
 	 */
-	bool		merged;
+	int			magnitude;
 } LocationLen;
 
 /*
-- 
2.41.0


--pjkjqtbeiiimipyr
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
	filename="v16-0004-Introduce-query_id_const_merge_threshold.patch"



^ permalink  raw  reply  [nested|flat] 9+ messages in thread

* [PATCH v17 3/4] Merge constants in ArrayExpr into groups
@ 2023-10-15 08:06  Dmitrii Dolgov <[email protected]>
  0 siblings, 0 replies; 9+ messages in thread

From: Dmitrii Dolgov @ 2023-10-15 08:06 UTC (permalink / raw)

Using query_id_const_merge only first/last element in an ArrayExpr will
be used to compute query id. Extend this to take into account number of
elements, and merge constants into groups based on it. Resulting groups
are powers of 10, i.e. 1 to 9, 10 to 99, etc.
---
 .../pg_stat_statements/expected/merging.out   | 84 +++++++++++++++----
 .../pg_stat_statements/pg_stat_statements.c   | 17 +++-
 contrib/pg_stat_statements/sql/merging.sql    | 13 +++
 doc/src/sgml/pgstatstatements.sgml            | 11 +--
 src/backend/nodes/queryjumblefuncs.c          | 52 ++++++++----
 src/include/nodes/queryjumble.h               |  7 +-
 6 files changed, 142 insertions(+), 42 deletions(-)

diff --git a/contrib/pg_stat_statements/expected/merging.out b/contrib/pg_stat_statements/expected/merging.out
index f286c735a36..7400870f3f6 100644
--- a/contrib/pg_stat_statements/expected/merging.out
+++ b/contrib/pg_stat_statements/expected/merging.out
@@ -54,11 +54,11 @@ SELECT * FROM test_merge WHERE id IN (1, 2, 3);
 (0 rows)
 
 SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
-                   query                    | calls 
---------------------------------------------+-------
- SELECT * FROM test_merge WHERE id IN ($1)  |     1
- SELECT * FROM test_merge WHERE id IN (...) |     1
- SELECT pg_stat_statements_reset()          |     1
+                          query                           | calls 
+----------------------------------------------------------+-------
+ SELECT * FROM test_merge WHERE id IN ($1)                |     1
+ SELECT * FROM test_merge WHERE id IN (... [1-9 entries]) |     1
+ SELECT pg_stat_statements_reset()                        |     1
 (3 rows)
 
 SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9);
@@ -80,7 +80,60 @@ SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
                                  query                                  | calls 
 ------------------------------------------------------------------------+-------
  SELECT * FROM test_merge WHERE id IN ($1)                              |     1
- SELECT * FROM test_merge WHERE id IN (...)                             |     4
+ SELECT * FROM test_merge WHERE id IN (... [1-9 entries])               |     2
+ SELECT * FROM test_merge WHERE id IN (... [10-99 entries])             |     2
+ SELECT pg_stat_statements_reset()                                      |     1
+ SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C" |     1
+(5 rows)
+
+-- Second order of magnitude, brace yourself
+SELECT pg_stat_statements_reset();
+ pg_stat_statements_reset 
+--------------------------
+ 
+(1 row)
+
+SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110);
+ id | data 
+----+------
+(0 rows)
+
+SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
+                            query                             | calls 
+--------------------------------------------------------------+-------
+ SELECT * FROM test_merge WHERE id IN (... [100-999 entries]) |     1
+ SELECT pg_stat_statements_reset()                            |     1
+(2 rows)
+
+-- With gaps on the threshold
+SELECT pg_stat_statements_reset();
+ pg_stat_statements_reset 
+--------------------------
+ 
+(1 row)
+
+SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4);
+ id | data 
+----+------
+(0 rows)
+
+SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
+                          query                           | calls 
+----------------------------------------------------------+-------
+ SELECT * FROM test_merge WHERE id IN (... [1-9 entries]) |     1
+ SELECT pg_stat_statements_reset()                        |     1
+(2 rows)
+
+SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15);
+ id | data 
+----+------
+(0 rows)
+
+SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
+                                 query                                  | calls 
+------------------------------------------------------------------------+-------
+ SELECT * FROM test_merge WHERE id IN (... [1-9 entries])               |     1
+ SELECT * FROM test_merge WHERE id IN (... [10-99 entries])             |     1
  SELECT pg_stat_statements_reset()                                      |     1
  SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C" |     1
 (4 rows)
@@ -108,11 +161,12 @@ SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11) and dat
 (0 rows)
 
 SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
-                          query                           | calls 
-----------------------------------------------------------+-------
- SELECT * FROM test_merge WHERE id IN (...) and data = $3 |     3
- SELECT pg_stat_statements_reset()                        |     1
-(2 rows)
+                                  query                                   | calls 
+--------------------------------------------------------------------------+-------
+ SELECT * FROM test_merge WHERE id IN (... [1-9 entries]) and data = $3   |     1
+ SELECT * FROM test_merge WHERE id IN (... [10-99 entries]) and data = $3 |     2
+ SELECT pg_stat_statements_reset()                                        |     1
+(3 rows)
 
 -- No constants simplification
 SELECT pg_stat_statements_reset();
@@ -147,10 +201,10 @@ SELECT * FROM test_merge_numeric WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
 (0 rows)
 
 SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
-                       query                        | calls 
-----------------------------------------------------+-------
- SELECT * FROM test_merge_numeric WHERE id IN (...) |     1
- SELECT pg_stat_statements_reset()                  |     1
+                               query                                | calls 
+--------------------------------------------------------------------+-------
+ SELECT * FROM test_merge_numeric WHERE id IN (... [10-99 entries]) |     1
+ SELECT pg_stat_statements_reset()                                  |     1
 (2 rows)
 
 -- Test constants evaluation, verifies a tricky part to make sure there are no
diff --git a/contrib/pg_stat_statements/pg_stat_statements.c b/contrib/pg_stat_statements/pg_stat_statements.c
index 4d47a746670..a5702c3d749 100644
--- a/contrib/pg_stat_statements/pg_stat_statements.c
+++ b/contrib/pg_stat_statements/pg_stat_statements.c
@@ -2714,6 +2714,8 @@ generate_normalized_query(JumbleState *jstate, const char *query,
 				last_tok_len = 0;	/* Length (in bytes) of that tok */
 	bool		skip = false; 	/* Signals that certain constants are
 								   merged together and have to be skipped */
+	int 		magnitude; 		/* Order of magnitute for number of merged
+								   constants */
 
 
 	/*
@@ -2754,7 +2756,8 @@ generate_normalized_query(JumbleState *jstate, const char *query,
 		Assert(len_to_wrt >= 0);
 
 		/* Normal path, non merged constant */
-		if (!jstate->clocations[i].merged)
+		magnitude = jstate->clocations[i].magnitude;
+		if (magnitude == 0)
 		{
 			memcpy(norm_query + n_quer_loc, query + quer_loc, len_to_wrt);
 			n_quer_loc += len_to_wrt;
@@ -2770,12 +2773,22 @@ generate_normalized_query(JumbleState *jstate, const char *query,
 		/* The firsts merged constant */
 		else if (!skip)
 		{
+			static const uint32 powers_of_ten[] = {
+				1, 10, 100,
+				1000, 10000, 100000,
+				1000000, 10000000, 100000000,
+				1000000000
+			};
+			int lower_merged = powers_of_ten[magnitude - 1];
+			int upper_merged = powers_of_ten[magnitude];
+
 			memcpy(norm_query + n_quer_loc, query + quer_loc, len_to_wrt);
 			n_quer_loc += len_to_wrt;
 
 			/* Skip the following until a non merged constant appear */
 			skip = true;
-			n_quer_loc += sprintf(norm_query + n_quer_loc, "...");
+			n_quer_loc += sprintf(norm_query + n_quer_loc, "... [%d-%d entries]",
+								  lower_merged, upper_merged - 1);
 		}
 		/* Otherwise the constant is merged away */
 
diff --git a/contrib/pg_stat_statements/sql/merging.sql b/contrib/pg_stat_statements/sql/merging.sql
index 8b589135daa..c515e48d50c 100644
--- a/contrib/pg_stat_statements/sql/merging.sql
+++ b/contrib/pg_stat_statements/sql/merging.sql
@@ -27,6 +27,19 @@ SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10);
 SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11);
 SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
 
+-- Second order of magnitude, brace yourself
+SELECT pg_stat_statements_reset();
+SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110);
+SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
+
+-- With gaps on the threshold
+SELECT pg_stat_statements_reset();
+SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4);
+SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
+
+SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15);
+SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
+
 -- More conditions in the query
 SELECT pg_stat_statements_reset();
 
diff --git a/doc/src/sgml/pgstatstatements.sgml b/doc/src/sgml/pgstatstatements.sgml
index c78140f8858..ff24153c493 100644
--- a/doc/src/sgml/pgstatstatements.sgml
+++ b/doc/src/sgml/pgstatstatements.sgml
@@ -560,7 +560,7 @@
 =# SELECT * FROM test WHERE a IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12);
 =# SELECT query, calls FROM pg_stat_statements;
 -[ RECORD 1 ]------------------------------
-query | SELECT * FROM test WHERE a IN (...)
+query | SELECT * FROM test WHERE a IN (... [10-99 entries])
 calls | 2
 -[ RECORD 2 ]------------------------------
 query | SELECT pg_stat_statements_reset()
@@ -897,10 +897,11 @@ calls | 1
       with an array of different lenght.
 
       If this parameter is on, an array of constants will contribute only the
-      first and the last elements to the query identifier. It means two
-      occurences of the same query, where the only difference is number of
-      constants in the array, are going to get the same query identifier.
-      Such queries are represented in form <literal>'(...)'</literal>.
+      first element, the last element and the number of elements to the query
+      identifier. It means two occurences of the same query, where the only
+      difference is number of constants in the array, are going to get the
+      same query identifier if the arrays are of similar length.
+      Such queries are represented in form <literal>'(... [10-99 entries])'</literal>.
 
       The parameter could be used to reduce amount of repeating data stored
       via <structname>pg_stat_statements</structname>.  The default value is off.
diff --git a/src/backend/nodes/queryjumblefuncs.c b/src/backend/nodes/queryjumblefuncs.c
index 4bc16dde6a0..a1d4567ca66 100644
--- a/src/backend/nodes/queryjumblefuncs.c
+++ b/src/backend/nodes/queryjumblefuncs.c
@@ -37,6 +37,8 @@
 #include "nodes/queryjumble.h"
 #include "parser/scansup.h"
 
+#include "utils/numutils.h"
+
 #define JUMBLE_SIZE				1024	/* query serialization buffer size */
 
 /* GUC parameters */
@@ -51,7 +53,7 @@ bool		query_id_enabled = false;
 static void AppendJumble(JumbleState *jstate,
 						 const unsigned char *item, Size size);
 static void RecordConstLocation(JumbleState *jstate,
-								int location, bool merged);
+								int location, int magnitude);
 static void _jumbleNode(JumbleState *jstate, Node *node);
 static void _jumbleElements(JumbleState *jstate, List *elements);
 static void _jumbleA_Const(JumbleState *jstate, Node *node);
@@ -206,12 +208,15 @@ AppendJumble(JumbleState *jstate, const unsigned char *item, Size size)
  * Record location of constant within query string of query tree that is
  * currently being walked.
  *
- * Merged argument signals that the constant represents the first or the last
- * element in a series of merged constants, and everything but the first/last
- * element contributes nothing to the jumble hash.
+ * Magnitude argument larger than zero signals that the constant represents the
+ * first or the last element in a series of merged constants, and everything
+ * but such first/last element will contribute nothing to the jumble hash. The
+ * magnitute value specifies order of magnitute (i.e. how many digits it has)
+ * for the number of elements in the series, to represent the fact of merging
+ * later on.
  */
 static void
-RecordConstLocation(JumbleState *jstate, int location, bool merged)
+RecordConstLocation(JumbleState *jstate, int location, int magnitude)
 {
 	/* -1 indicates unknown or undefined location */
 	if (location >= 0)
@@ -227,7 +232,7 @@ RecordConstLocation(JumbleState *jstate, int location, bool merged)
 		}
 		jstate->clocations[jstate->clocations_count].location = location;
 		/* initialize lengths to -1 to simplify third-party module usage */
-		jstate->clocations[jstate->clocations_count].merged = merged;
+		jstate->clocations[jstate->clocations_count].magnitude = magnitude;
 		jstate->clocations[jstate->clocations_count].length = -1;
 		jstate->clocations_count++;
 	}
@@ -237,24 +242,26 @@ RecordConstLocation(JumbleState *jstate, int location, bool merged)
  * Verify if the provided list contains could be merged down, which means it
  * contains only constant expressions.
  *
- * Return value indicates if merging is possible.
+ * Return value is the order of magnitude (i.e. how many digits it has) for
+ * length of the list (to use for representation purposes later on) if merging
+ * is possible, otherwise zero.
  *
  * Note that this function searches only for explicit Const nodes and does not
  * try to simplify expressions.
  */
-static bool
+static int
 IsMergeableConstList(List *elements, Const **firstConst, Const **lastConst)
 {
 	ListCell   *temp;
 	Node	   *firstExpr = NULL;
 
 	if (elements == NULL)
-		return false;
+		return 0;
 
 	if (!query_id_const_merge)
 	{
 		/* Merging is disabled, process everything one by one */
-		return false;
+		return 0;
 	}
 
 	firstExpr = linitial(elements);
@@ -268,26 +275,26 @@ IsMergeableConstList(List *elements, Const **firstConst, Const **lastConst)
 	{
 		foreach(temp, elements)
 			if (!IsA(lfirst(temp), Const))
-				return false;
+				return 0;
 
 		*firstConst = (Const *) firstExpr;
 		*lastConst = llast_node(Const, elements);
-		return true;
+		return decimalLength32(elements->length);
 	}
 
 	/*
 	 * If we end up here, it means no constants merging is possible, process
 	 * the list as usual.
 	 */
-	return false;
+	return 0;
 }
 
 #define JUMBLE_NODE(item) \
 	_jumbleNode(jstate, (Node *) expr->item)
 #define JUMBLE_ELEMENTS(list) \
 	_jumbleElements(jstate, (List *) expr->list)
-#define JUMBLE_LOCATION(location, merged) \
-	RecordConstLocation(jstate, expr->location, merged)
+#define JUMBLE_LOCATION(location, magnitude) \
+	RecordConstLocation(jstate, expr->location, magnitude)
 #define JUMBLE_FIELD(item) \
 	AppendJumble(jstate, (const unsigned char *) &(expr->item), sizeof(expr->item))
 #define JUMBLE_FIELD_SINGLE(item) \
@@ -304,10 +311,19 @@ static void
 _jumbleElements(JumbleState *jstate, List *elements)
 {
 	Const *first, *last;
-	if(IsMergeableConstList(elements, &first, &last))
+	int magnitude = IsMergeableConstList(elements, &first, &last);
+
+	if (magnitude)
 	{
-		RecordConstLocation(jstate, first->location, true);
-		RecordConstLocation(jstate, last->location, true);
+		RecordConstLocation(jstate, first->location, magnitude);
+		RecordConstLocation(jstate, last->location, magnitude);
+
+		/*
+		 * After merging constants down we end up with only two constants, the
+		 * first and the last one. To distinguish the order of magnitute behind
+		 * merged constants, add its value into the jumble.
+		 */
+		JUMBLE_FIELD_SINGLE(magnitude);
 	}
 	else
 	{
diff --git a/src/include/nodes/queryjumble.h b/src/include/nodes/queryjumble.h
index c64a007ad3f..8ee2e9afbb6 100644
--- a/src/include/nodes/queryjumble.h
+++ b/src/include/nodes/queryjumble.h
@@ -26,9 +26,12 @@ typedef struct LocationLen
 
 	/*
 	 * Indicates the constant represents the beginning or the end of a merged
-	 * constants interval.
+	 * constants interval. The value shows how many constants were merged away
+	 * (up to a power of 10), or in other words the order of manitude for
+	 * number of merged constants (i.e. how many digits it has). Otherwise the
+	 * value is 0, indicating that no merging was performed.
 	 */
-	bool		merged;
+	int			magnitude;
 } LocationLen;
 
 /*
-- 
2.41.0


--si27d3bgnnpsswlv
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
	filename="v17-0004-Introduce-query_id_const_merge_threshold.patch"



^ permalink  raw  reply  [nested|flat] 9+ messages in thread

* [PATCH v15 3/4] Merge constants in ArrayExpr into groups
@ 2023-10-15 08:06  Dmitrii Dolgov <[email protected]>
  0 siblings, 0 replies; 9+ messages in thread

From: Dmitrii Dolgov @ 2023-10-15 08:06 UTC (permalink / raw)

Using query_id_const_merge only first/last element in an ArrayExpr will
be used to compute query id. Extend this to take into account number of
elements, and merge constants into groups based on it. Resulting groups
are powers of 10, i.e. 1 to 9, 10 to 99, etc.
---
 .../pg_stat_statements/expected/merging.out   | 84 +++++++++++++++----
 .../pg_stat_statements/pg_stat_statements.c   | 17 +++-
 contrib/pg_stat_statements/sql/merging.sql    | 13 +++
 doc/src/sgml/config.sgml                      |  9 +-
 doc/src/sgml/pgstatstatements.sgml            |  2 +-
 src/backend/nodes/queryjumblefuncs.c          | 52 ++++++++----
 src/include/nodes/queryjumble.h               |  7 +-
 7 files changed, 142 insertions(+), 42 deletions(-)

diff --git a/contrib/pg_stat_statements/expected/merging.out b/contrib/pg_stat_statements/expected/merging.out
index 7711572e0b7..1bb75a93045 100644
--- a/contrib/pg_stat_statements/expected/merging.out
+++ b/contrib/pg_stat_statements/expected/merging.out
@@ -54,11 +54,11 @@ SELECT * FROM test_merge WHERE id IN (1, 2, 3);
 (0 rows)
 
 SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
-                   query                    | calls 
---------------------------------------------+-------
- SELECT * FROM test_merge WHERE id IN ($1)  |     1
- SELECT * FROM test_merge WHERE id IN (...) |     1
- SELECT pg_stat_statements_reset()          |     1
+                          query                           | calls 
+----------------------------------------------------------+-------
+ SELECT * FROM test_merge WHERE id IN ($1)                |     1
+ SELECT * FROM test_merge WHERE id IN (... [1-9 entries]) |     1
+ SELECT pg_stat_statements_reset()                        |     1
 (3 rows)
 
 SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9);
@@ -80,7 +80,60 @@ SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
                                  query                                  | calls 
 ------------------------------------------------------------------------+-------
  SELECT * FROM test_merge WHERE id IN ($1)                              |     1
- SELECT * FROM test_merge WHERE id IN (...)                             |     4
+ SELECT * FROM test_merge WHERE id IN (... [1-9 entries])               |     2
+ SELECT * FROM test_merge WHERE id IN (... [10-99 entries])             |     2
+ SELECT pg_stat_statements_reset()                                      |     1
+ SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C" |     1
+(5 rows)
+
+-- Second order of magnitude, brace yourself
+SELECT pg_stat_statements_reset();
+ pg_stat_statements_reset 
+--------------------------
+ 
+(1 row)
+
+SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110);
+ id | data 
+----+------
+(0 rows)
+
+SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
+                            query                             | calls 
+--------------------------------------------------------------+-------
+ SELECT * FROM test_merge WHERE id IN (... [100-999 entries]) |     1
+ SELECT pg_stat_statements_reset()                            |     1
+(2 rows)
+
+-- With gaps on the threshold
+SELECT pg_stat_statements_reset();
+ pg_stat_statements_reset 
+--------------------------
+ 
+(1 row)
+
+SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4);
+ id | data 
+----+------
+(0 rows)
+
+SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
+                          query                           | calls 
+----------------------------------------------------------+-------
+ SELECT * FROM test_merge WHERE id IN (... [1-9 entries]) |     1
+ SELECT pg_stat_statements_reset()                        |     1
+(2 rows)
+
+SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15);
+ id | data 
+----+------
+(0 rows)
+
+SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
+                                 query                                  | calls 
+------------------------------------------------------------------------+-------
+ SELECT * FROM test_merge WHERE id IN (... [1-9 entries])               |     1
+ SELECT * FROM test_merge WHERE id IN (... [10-99 entries])             |     1
  SELECT pg_stat_statements_reset()                                      |     1
  SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C" |     1
 (4 rows)
@@ -108,11 +161,12 @@ SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11) and dat
 (0 rows)
 
 SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
-                          query                           | calls 
-----------------------------------------------------------+-------
- SELECT * FROM test_merge WHERE id IN (...) and data = $3 |     3
- SELECT pg_stat_statements_reset()                        |     1
-(2 rows)
+                                  query                                   | calls 
+--------------------------------------------------------------------------+-------
+ SELECT * FROM test_merge WHERE id IN (... [1-9 entries]) and data = $3   |     1
+ SELECT * FROM test_merge WHERE id IN (... [10-99 entries]) and data = $3 |     2
+ SELECT pg_stat_statements_reset()                                        |     1
+(3 rows)
 
 -- No constants simplification
 SELECT pg_stat_statements_reset();
@@ -147,10 +201,10 @@ SELECT * FROM test_merge_numeric WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
 (0 rows)
 
 SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
-                       query                        | calls 
-----------------------------------------------------+-------
- SELECT * FROM test_merge_numeric WHERE id IN (...) |     1
- SELECT pg_stat_statements_reset()                  |     1
+                               query                                | calls 
+--------------------------------------------------------------------+-------
+ SELECT * FROM test_merge_numeric WHERE id IN (... [10-99 entries]) |     1
+ SELECT pg_stat_statements_reset()                                  |     1
 (2 rows)
 
 -- Test constants evaluation, verifies a tricky part to make sure there are no
diff --git a/contrib/pg_stat_statements/pg_stat_statements.c b/contrib/pg_stat_statements/pg_stat_statements.c
index 0b03009a053..24d7401257d 100644
--- a/contrib/pg_stat_statements/pg_stat_statements.c
+++ b/contrib/pg_stat_statements/pg_stat_statements.c
@@ -2697,6 +2697,8 @@ generate_normalized_query(JumbleState *jstate, const char *query,
 				last_tok_len = 0;	/* Length (in bytes) of that tok */
 	bool		skip = false; 	/* Signals that certain constants are
 								   merged together and have to be skipped */
+	int 		magnitude; 		/* Order of magnitute for number of merged
+								   constants */
 
 
 	/*
@@ -2737,7 +2739,8 @@ generate_normalized_query(JumbleState *jstate, const char *query,
 		Assert(len_to_wrt >= 0);
 
 		/* Normal path, non merged constant */
-		if (!jstate->clocations[i].merged)
+		magnitude = jstate->clocations[i].magnitude;
+		if (magnitude == 0)
 		{
 			memcpy(norm_query + n_quer_loc, query + quer_loc, len_to_wrt);
 			n_quer_loc += len_to_wrt;
@@ -2753,12 +2756,22 @@ generate_normalized_query(JumbleState *jstate, const char *query,
 		/* The firsts merged constant */
 		else if (!skip)
 		{
+			static const uint32 powers_of_ten[] = {
+				1, 10, 100,
+				1000, 10000, 100000,
+				1000000, 10000000, 100000000,
+				1000000000
+			};
+			int lower_merged = powers_of_ten[magnitude - 1];
+			int upper_merged = powers_of_ten[magnitude];
+
 			memcpy(norm_query + n_quer_loc, query + quer_loc, len_to_wrt);
 			n_quer_loc += len_to_wrt;
 
 			/* Skip the following until a non merged constant appear */
 			skip = true;
-			n_quer_loc += sprintf(norm_query + n_quer_loc, "...");
+			n_quer_loc += sprintf(norm_query + n_quer_loc, "... [%d-%d entries]",
+								  lower_merged, upper_merged - 1);
 		}
 		/* Otherwise the constant is merged away */
 
diff --git a/contrib/pg_stat_statements/sql/merging.sql b/contrib/pg_stat_statements/sql/merging.sql
index 02266a92ce8..75960159a1d 100644
--- a/contrib/pg_stat_statements/sql/merging.sql
+++ b/contrib/pg_stat_statements/sql/merging.sql
@@ -27,6 +27,19 @@ SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10);
 SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11);
 SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
 
+-- Second order of magnitude, brace yourself
+SELECT pg_stat_statements_reset();
+SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110);
+SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
+
+-- With gaps on the threshold
+SELECT pg_stat_statements_reset();
+SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4);
+SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
+
+SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15);
+SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
+
 -- More conditions in the query
 SELECT pg_stat_statements_reset();
 
diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml
index 55b0795bce1..4fd997284c9 100644
--- a/doc/src/sgml/config.sgml
+++ b/doc/src/sgml/config.sgml
@@ -8205,15 +8205,16 @@ COPY postgres_log FROM '/full/path/to/logfile.csv' WITH csv;
         with an array of different lenght.
 
         If this parameter is on, an array of constants will contribute only the
-        first and the last elements to the query identifier. It means two
-        occurences of the same query, where the only difference is number of
-        constants in the array, are going to get the same query identifier.
+        first element, the last element and the number of elements to the query
+        identifier. It means two occurences of the same query, where the only
+        difference is number of constants in the array, are going to get the
+        same query identifier if the arrays are of similar length.
 
         The parameter could be used to reduce amount of repeating data stored
         via <xref linkend="pgstatstatements"/> extension.  The default value is off.
 
         The <xref linkend="pgstatstatements"/> extension will represent such
-        queries in form <literal>'(...)'</literal>.
+        queries in form <literal>'(... [10-99 entries])'</literal>.
        </para>
       </listitem>
      </varlistentry>
diff --git a/doc/src/sgml/pgstatstatements.sgml b/doc/src/sgml/pgstatstatements.sgml
index 8df4064cbf4..1f6e6a0e76b 100644
--- a/doc/src/sgml/pgstatstatements.sgml
+++ b/doc/src/sgml/pgstatstatements.sgml
@@ -559,7 +559,7 @@
 =# SELECT * FROM test WHERE a IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12);
 =# SELECT query, calls FROM pg_stat_statements;
 -[ RECORD 1 ]------------------------------
-query | SELECT * FROM test WHERE a IN (...)
+query | SELECT * FROM test WHERE a IN (... [10-99 entries])
 calls | 2
 -[ RECORD 2 ]------------------------------
 query | SELECT pg_stat_statements_reset()
diff --git a/src/backend/nodes/queryjumblefuncs.c b/src/backend/nodes/queryjumblefuncs.c
index 52d45c2b093..b198fe2579e 100644
--- a/src/backend/nodes/queryjumblefuncs.c
+++ b/src/backend/nodes/queryjumblefuncs.c
@@ -37,6 +37,8 @@
 #include "nodes/queryjumble.h"
 #include "parser/scansup.h"
 
+#include "utils/numutils.h"
+
 #define JUMBLE_SIZE				1024	/* query serialization buffer size */
 
 /* GUC parameters */
@@ -51,7 +53,7 @@ bool		query_id_enabled = false;
 static void AppendJumble(JumbleState *jstate,
 						 const unsigned char *item, Size size);
 static void RecordConstLocation(JumbleState *jstate,
-								int location, bool merged);
+								int location, int magnitude);
 static void _jumbleNode(JumbleState *jstate, Node *node);
 static void _jumbleA_Const(JumbleState *jstate, Node *node);
 static void _jumbleList(JumbleState *jstate, Node *node);
@@ -193,12 +195,15 @@ AppendJumble(JumbleState *jstate, const unsigned char *item, Size size)
  * Record location of constant within query string of query tree that is
  * currently being walked.
  *
- * Merged argument signals that the constant represents the first or the last
- * element in a series of merged constants, and everything but the first/last
- * element contributes nothing to the jumble hash.
+ * Magnitude argument larger than zero signals that the constant represents the
+ * first or the last element in a series of merged constants, and everything
+ * but such first/last element will contribute nothing to the jumble hash. The
+ * magnitute value specifies order of magnitute (i.e. how many digits it has)
+ * for the number of elements in the series, to represent the fact of merging
+ * later on.
  */
 static void
-RecordConstLocation(JumbleState *jstate, int location, bool merged)
+RecordConstLocation(JumbleState *jstate, int location, int magnitude)
 {
 	/* -1 indicates unknown or undefined location */
 	if (location >= 0)
@@ -214,7 +219,7 @@ RecordConstLocation(JumbleState *jstate, int location, bool merged)
 		}
 		jstate->clocations[jstate->clocations_count].location = location;
 		/* initialize lengths to -1 to simplify third-party module usage */
-		jstate->clocations[jstate->clocations_count].merged = merged;
+		jstate->clocations[jstate->clocations_count].magnitude = magnitude;
 		jstate->clocations[jstate->clocations_count].length = -1;
 		jstate->clocations_count++;
 	}
@@ -224,24 +229,26 @@ RecordConstLocation(JumbleState *jstate, int location, bool merged)
  * Verify if the provided list contains could be merged down, which means it
  * contains only constant expressions.
  *
- * Return value indicates if merging is possible.
+ * Return value is the order of magnitude (i.e. how many digits it has) for
+ * length of the list (to use for representation purposes later on) if merging
+ * is possible, otherwise zero.
  *
  * Note that this function searches only for explicit Const nodes and does not
  * try to simplify expressions.
  */
-static bool
+static int
 IsMergeableConstList(List *elements, Const **firstConst, Const **lastConst)
 {
 	ListCell   *temp;
 	Node	   *firstExpr = NULL;
 
 	if (elements == NULL)
-		return false;
+		return 0;
 
 	if (!query_id_const_merge)
 	{
 		/* Merging is disabled, process everything one by one */
-		return false;
+		return 0;
 	}
 
 	firstExpr = linitial(elements);
@@ -255,24 +262,24 @@ IsMergeableConstList(List *elements, Const **firstConst, Const **lastConst)
 	{
 		foreach(temp, elements)
 			if (!IsA(lfirst(temp), Const))
-				return false;
+				return 0;
 
 		*firstConst = (Const *) firstExpr;
 		*lastConst = llast_node(Const, elements);
-		return true;
+		return decimalLength32(elements->length);
 	}
 
 	/*
 	 * If we end up here, it means no constants merging is possible, process
 	 * the list as usual.
 	 */
-	return false;
+	return 0;
 }
 
 #define JUMBLE_NODE(item) \
 	_jumbleNode(jstate, (Node *) expr->item)
-#define JUMBLE_LOCATION(location, merged) \
-	RecordConstLocation(jstate, expr->location, merged)
+#define JUMBLE_LOCATION(location, magnitude) \
+	RecordConstLocation(jstate, expr->location, magnitude)
 #define JUMBLE_FIELD(item) \
 	AppendJumble(jstate, (const unsigned char *) &(expr->item), sizeof(expr->item))
 #define JUMBLE_FIELD_SINGLE(item) \
@@ -290,10 +297,19 @@ _jumbleArrayExpr(JumbleState *jstate, Node *node)
 {
 	ArrayExpr *expr = (ArrayExpr *) node;
 	Const *first, *last;
-	if(IsMergeableConstList(expr->elements, &first, &last))
+	int magnitude = IsMergeableConstList(expr->elements, &first, &last);
+
+	if (magnitude)
 	{
-		RecordConstLocation(jstate, first->location, true);
-		RecordConstLocation(jstate, last->location, true);
+		RecordConstLocation(jstate, first->location, magnitude);
+		RecordConstLocation(jstate, last->location, magnitude);
+
+		/*
+		 * After merging constants down we end up with only two constants, the
+		 * first and the last one. To distinguish the order of magnitute behind
+		 * merged constants, add its value into the jumble.
+		 */
+		JUMBLE_FIELD_SINGLE(magnitude);
 	}
 	else
 	{
diff --git a/src/include/nodes/queryjumble.h b/src/include/nodes/queryjumble.h
index 225957d7b3c..cfa99efc14e 100644
--- a/src/include/nodes/queryjumble.h
+++ b/src/include/nodes/queryjumble.h
@@ -27,9 +27,12 @@ typedef struct LocationLen
 
 	/*
 	 * Indicates the constant represents the beginning or the end of a merged
-	 * constants interval.
+	 * constants interval. The value shows how many constants were merged away
+	 * (up to a power of 10), or in other words the order of manitude for
+	 * number of merged constants (i.e. how many digits it has). Otherwise the
+	 * value is 0, indicating that no merging was performed.
 	 */
-	bool		merged;
+	int			magnitude;
 } LocationLen;
 
 /*
-- 
2.41.0


--svnhsmawrtczycxj
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
	filename="v15-0004-Add-query_id_const_merge_threshold.patch"



^ permalink  raw  reply  [nested|flat] 9+ messages in thread

* [PATCH v19 3/4] Merge constants in ArrayExpr into groups
@ 2024-01-22 20:20  Dmitrii Dolgov <[email protected]>
  0 siblings, 0 replies; 9+ messages in thread

From: Dmitrii Dolgov @ 2024-01-22 20:20 UTC (permalink / raw)

Using query_id_const_merge only first/last element in an ArrayExpr will
be used to compute query id. Extend this to take into account number of
elements, and merge constants into groups based on it. Resulting groups
are powers of 10, i.e. 1 to 9, 10 to 99, etc.
---
 .../pg_stat_statements/expected/merging.out   | 84 +++++++++++++++----
 .../pg_stat_statements/pg_stat_statements.c   | 17 +++-
 contrib/pg_stat_statements/sql/merging.sql    | 13 +++
 doc/src/sgml/pgstatstatements.sgml            | 11 +--
 src/backend/nodes/queryjumblefuncs.c          | 52 ++++++++----
 src/include/nodes/queryjumble.h               |  7 +-
 6 files changed, 142 insertions(+), 42 deletions(-)

diff --git a/contrib/pg_stat_statements/expected/merging.out b/contrib/pg_stat_statements/expected/merging.out
index 1e58283afe8..0cb4f67b8b7 100644
--- a/contrib/pg_stat_statements/expected/merging.out
+++ b/contrib/pg_stat_statements/expected/merging.out
@@ -54,11 +54,11 @@ SELECT * FROM test_merge WHERE id IN (1, 2, 3);
 (0 rows)
 
 SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
-                       query                        | calls 
-----------------------------------------------------+-------
- SELECT * FROM test_merge WHERE id IN ($1)          |     1
- SELECT * FROM test_merge WHERE id IN (...)         |     1
- SELECT pg_stat_statements_reset() IS NOT NULL AS t |     1
+                          query                           | calls 
+----------------------------------------------------------+-------
+ SELECT * FROM test_merge WHERE id IN ($1)                |     1
+ SELECT * FROM test_merge WHERE id IN (... [1-9 entries]) |     1
+ SELECT pg_stat_statements_reset() IS NOT NULL AS t       |     1
 (3 rows)
 
 SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9);
@@ -80,7 +80,60 @@ SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
                                  query                                  | calls 
 ------------------------------------------------------------------------+-------
  SELECT * FROM test_merge WHERE id IN ($1)                              |     1
- SELECT * FROM test_merge WHERE id IN (...)                             |     4
+ SELECT * FROM test_merge WHERE id IN (... [1-9 entries])               |     2
+ SELECT * FROM test_merge WHERE id IN (... [10-99 entries])             |     2
+ SELECT pg_stat_statements_reset() IS NOT NULL AS t                     |     1
+ SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C" |     1
+(5 rows)
+
+-- Second order of magnitude, brace yourself
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110);
+ id | data 
+----+------
+(0 rows)
+
+SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
+                            query                             | calls 
+--------------------------------------------------------------+-------
+ SELECT * FROM test_merge WHERE id IN (... [100-999 entries]) |     1
+ SELECT pg_stat_statements_reset() IS NOT NULL AS t           |     1
+(2 rows)
+
+-- With gaps on the threshold
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4);
+ id | data 
+----+------
+(0 rows)
+
+SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
+                          query                           | calls 
+----------------------------------------------------------+-------
+ SELECT * FROM test_merge WHERE id IN (... [1-9 entries]) |     1
+ SELECT pg_stat_statements_reset() IS NOT NULL AS t       |     1
+(2 rows)
+
+SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15);
+ id | data 
+----+------
+(0 rows)
+
+SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
+                                 query                                  | calls 
+------------------------------------------------------------------------+-------
+ SELECT * FROM test_merge WHERE id IN (... [1-9 entries])               |     1
+ SELECT * FROM test_merge WHERE id IN (... [10-99 entries])             |     1
  SELECT pg_stat_statements_reset() IS NOT NULL AS t                     |     1
  SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C" |     1
 (4 rows)
@@ -108,11 +161,12 @@ SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11) and dat
 (0 rows)
 
 SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
-                          query                           | calls 
-----------------------------------------------------------+-------
- SELECT * FROM test_merge WHERE id IN (...) and data = $3 |     3
- SELECT pg_stat_statements_reset() IS NOT NULL AS t       |     1
-(2 rows)
+                                  query                                   | calls 
+--------------------------------------------------------------------------+-------
+ SELECT * FROM test_merge WHERE id IN (... [1-9 entries]) and data = $3   |     1
+ SELECT * FROM test_merge WHERE id IN (... [10-99 entries]) and data = $3 |     2
+ SELECT pg_stat_statements_reset() IS NOT NULL AS t                       |     1
+(3 rows)
 
 -- No constants simplification
 SELECT pg_stat_statements_reset() IS NOT NULL AS t;
@@ -147,10 +201,10 @@ SELECT * FROM test_merge_numeric WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
 (0 rows)
 
 SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
-                       query                        | calls 
-----------------------------------------------------+-------
- SELECT * FROM test_merge_numeric WHERE id IN (...) |     1
- SELECT pg_stat_statements_reset() IS NOT NULL AS t |     1
+                               query                                | calls 
+--------------------------------------------------------------------+-------
+ SELECT * FROM test_merge_numeric WHERE id IN (... [10-99 entries]) |     1
+ SELECT pg_stat_statements_reset() IS NOT NULL AS t                 |     1
 (2 rows)
 
 -- Test constants evaluation, verifies a tricky part to make sure there are no
diff --git a/contrib/pg_stat_statements/pg_stat_statements.c b/contrib/pg_stat_statements/pg_stat_statements.c
index d7841b51cc9..00eec30feb1 100644
--- a/contrib/pg_stat_statements/pg_stat_statements.c
+++ b/contrib/pg_stat_statements/pg_stat_statements.c
@@ -2827,6 +2827,8 @@ generate_normalized_query(JumbleState *jstate, const char *query,
 				last_tok_len = 0;	/* Length (in bytes) of that tok */
 	bool		skip = false; 	/* Signals that certain constants are
 								   merged together and have to be skipped */
+	int 		magnitude; 		/* Order of magnitute for number of merged
+								   constants */
 
 
 	/*
@@ -2867,7 +2869,8 @@ generate_normalized_query(JumbleState *jstate, const char *query,
 		Assert(len_to_wrt >= 0);
 
 		/* Normal path, non merged constant */
-		if (!jstate->clocations[i].merged)
+		magnitude = jstate->clocations[i].magnitude;
+		if (magnitude == 0)
 		{
 			memcpy(norm_query + n_quer_loc, query + quer_loc, len_to_wrt);
 			n_quer_loc += len_to_wrt;
@@ -2883,12 +2886,22 @@ generate_normalized_query(JumbleState *jstate, const char *query,
 		/* The firsts merged constant */
 		else if (!skip)
 		{
+			static const uint32 powers_of_ten[] = {
+				1, 10, 100,
+				1000, 10000, 100000,
+				1000000, 10000000, 100000000,
+				1000000000
+			};
+			int lower_merged = powers_of_ten[magnitude - 1];
+			int upper_merged = powers_of_ten[magnitude];
+
 			memcpy(norm_query + n_quer_loc, query + quer_loc, len_to_wrt);
 			n_quer_loc += len_to_wrt;
 
 			/* Skip the following until a non merged constant appear */
 			skip = true;
-			n_quer_loc += sprintf(norm_query + n_quer_loc, "...");
+			n_quer_loc += sprintf(norm_query + n_quer_loc, "... [%d-%d entries]",
+								  lower_merged, upper_merged - 1);
 		}
 		/* Otherwise the constant is merged away */
 
diff --git a/contrib/pg_stat_statements/sql/merging.sql b/contrib/pg_stat_statements/sql/merging.sql
index 71985bb1cd9..657044faded 100644
--- a/contrib/pg_stat_statements/sql/merging.sql
+++ b/contrib/pg_stat_statements/sql/merging.sql
@@ -27,6 +27,19 @@ SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10);
 SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11);
 SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
 
+-- Second order of magnitude, brace yourself
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110);
+SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
+
+-- With gaps on the threshold
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4);
+SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
+
+SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15);
+SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
+
 -- More conditions in the query
 SELECT pg_stat_statements_reset() IS NOT NULL AS t;
 
diff --git a/doc/src/sgml/pgstatstatements.sgml b/doc/src/sgml/pgstatstatements.sgml
index 2b4c142f647..bac029430be 100644
--- a/doc/src/sgml/pgstatstatements.sgml
+++ b/doc/src/sgml/pgstatstatements.sgml
@@ -616,7 +616,7 @@
 =# SELECT * FROM test WHERE a IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12);
 =# SELECT query, calls FROM pg_stat_statements;
 -[ RECORD 1 ]------------------------------
-query | SELECT * FROM test WHERE a IN (...)
+query | SELECT * FROM test WHERE a IN (... [10-99 entries])
 calls | 2
 -[ RECORD 2 ]------------------------------
 query | SELECT pg_stat_statements_reset()
@@ -968,10 +968,11 @@ calls | 1
       with an array of different lenght.
 
       If this parameter is on, an array of constants will contribute only the
-      first and the last elements to the query identifier. It means two
-      occurences of the same query, where the only difference is number of
-      constants in the array, are going to get the same query identifier.
-      Such queries are represented in form <literal>'(...)'</literal>.
+      first element, the last element and the number of elements to the query
+      identifier. It means two occurences of the same query, where the only
+      difference is number of constants in the array, are going to get the
+      same query identifier if the arrays are of similar length.
+      Such queries are represented in form <literal>'(... [10-99 entries])'</literal>.
 
       The parameter could be used to reduce amount of repeating data stored
       via <structname>pg_stat_statements</structname>.  The default value is off.
diff --git a/src/backend/nodes/queryjumblefuncs.c b/src/backend/nodes/queryjumblefuncs.c
index e9473def361..a27202cb279 100644
--- a/src/backend/nodes/queryjumblefuncs.c
+++ b/src/backend/nodes/queryjumblefuncs.c
@@ -37,6 +37,8 @@
 #include "nodes/queryjumble.h"
 #include "parser/scansup.h"
 
+#include "utils/numutils.h"
+
 #define JUMBLE_SIZE				1024	/* query serialization buffer size */
 
 /* GUC parameters */
@@ -57,7 +59,7 @@ bool		query_id_enabled = false;
 static void AppendJumble(JumbleState *jstate,
 						 const unsigned char *item, Size size);
 static void RecordConstLocation(JumbleState *jstate,
-								int location, bool merged);
+								int location, int magnitude);
 static void _jumbleNode(JumbleState *jstate, Node *node);
 static void _jumbleElements(JumbleState *jstate, List *elements);
 static void _jumbleA_Const(JumbleState *jstate, Node *node);
@@ -212,12 +214,15 @@ AppendJumble(JumbleState *jstate, const unsigned char *item, Size size)
  * Record location of constant within query string of query tree that is
  * currently being walked.
  *
- * Merged argument signals that the constant represents the first or the last
- * element in a series of merged constants, and everything but the first/last
- * element contributes nothing to the jumble hash.
+ * Magnitude argument larger than zero signals that the constant represents the
+ * first or the last element in a series of merged constants, and everything
+ * but such first/last element will contribute nothing to the jumble hash. The
+ * magnitute value specifies order of magnitute (i.e. how many digits it has)
+ * for the number of elements in the series, to represent the fact of merging
+ * later on.
  */
 static void
-RecordConstLocation(JumbleState *jstate, int location, bool merged)
+RecordConstLocation(JumbleState *jstate, int location, int magnitude)
 {
 	/* -1 indicates unknown or undefined location */
 	if (location >= 0)
@@ -233,7 +238,7 @@ RecordConstLocation(JumbleState *jstate, int location, bool merged)
 		}
 		jstate->clocations[jstate->clocations_count].location = location;
 		/* initialize lengths to -1 to simplify third-party module usage */
-		jstate->clocations[jstate->clocations_count].merged = merged;
+		jstate->clocations[jstate->clocations_count].magnitude = magnitude;
 		jstate->clocations[jstate->clocations_count].length = -1;
 		jstate->clocations_count++;
 	}
@@ -243,24 +248,26 @@ RecordConstLocation(JumbleState *jstate, int location, bool merged)
  * Verify if the provided list contains could be merged down, which means it
  * contains only constant expressions.
  *
- * Return value indicates if merging is possible.
+ * Return value is the order of magnitude (i.e. how many digits it has) for
+ * length of the list (to use for representation purposes later on) if merging
+ * is possible, otherwise zero.
  *
  * Note that this function searches only for explicit Const nodes and does not
  * try to simplify expressions.
  */
-static bool
+static int
 IsMergeableConstList(List *elements, Const **firstConst, Const **lastConst)
 {
 	ListCell   *temp;
 	Node	   *firstExpr = NULL;
 
 	if (elements == NULL)
-		return false;
+		return 0;
 
 	if (!query_id_const_merge)
 	{
 		/* Merging is disabled, process everything one by one */
-		return false;
+		return 0;
 	}
 
 	firstExpr = linitial(elements);
@@ -274,26 +281,26 @@ IsMergeableConstList(List *elements, Const **firstConst, Const **lastConst)
 	{
 		foreach(temp, elements)
 			if (!IsA(lfirst(temp), Const))
-				return false;
+				return 0;
 
 		*firstConst = (Const *) firstExpr;
 		*lastConst = llast_node(Const, elements);
-		return true;
+		return decimalLength32(elements->length);
 	}
 
 	/*
 	 * If we end up here, it means no constants merging is possible, process
 	 * the list as usual.
 	 */
-	return false;
+	return 0;
 }
 
 #define JUMBLE_NODE(item) \
 	_jumbleNode(jstate, (Node *) expr->item)
 #define JUMBLE_ELEMENTS(list) \
 	_jumbleElements(jstate, (List *) expr->list)
-#define JUMBLE_LOCATION(location, merged) \
-	RecordConstLocation(jstate, expr->location, merged)
+#define JUMBLE_LOCATION(location, magnitude) \
+	RecordConstLocation(jstate, expr->location, magnitude)
 #define JUMBLE_FIELD(item) \
 	AppendJumble(jstate, (const unsigned char *) &(expr->item), sizeof(expr->item))
 #define JUMBLE_FIELD_SINGLE(item) \
@@ -310,10 +317,19 @@ static void
 _jumbleElements(JumbleState *jstate, List *elements)
 {
 	Const *first, *last;
-	if(IsMergeableConstList(elements, &first, &last))
+	int magnitude = IsMergeableConstList(elements, &first, &last);
+
+	if (magnitude)
 	{
-		RecordConstLocation(jstate, first->location, true);
-		RecordConstLocation(jstate, last->location, true);
+		RecordConstLocation(jstate, first->location, magnitude);
+		RecordConstLocation(jstate, last->location, magnitude);
+
+		/*
+		 * After merging constants down we end up with only two constants, the
+		 * first and the last one. To distinguish the order of magnitute behind
+		 * merged constants, add its value into the jumble.
+		 */
+		JUMBLE_FIELD_SINGLE(magnitude);
 	}
 	else
 	{
diff --git a/src/include/nodes/queryjumble.h b/src/include/nodes/queryjumble.h
index 8daf0725d7f..551555494e0 100644
--- a/src/include/nodes/queryjumble.h
+++ b/src/include/nodes/queryjumble.h
@@ -26,9 +26,12 @@ typedef struct LocationLen
 
 	/*
 	 * Indicates the constant represents the beginning or the end of a merged
-	 * constants interval.
+	 * constants interval. The value shows how many constants were merged away
+	 * (up to a power of 10), or in other words the order of manitude for
+	 * number of merged constants (i.e. how many digits it has). Otherwise the
+	 * value is 0, indicating that no merging was performed.
 	 */
-	bool		merged;
+	int			magnitude;
 } LocationLen;
 
 /*
-- 
2.41.0


--yzrwxjftwx5vp4wd
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
	filename="v19-0004-Introduce-query_id_const_merge_threshold.patch"



^ permalink  raw  reply  [nested|flat] 9+ messages in thread

* [PATCH v18 3/4] Merge constants in ArrayExpr into groups
@ 2024-01-22 20:20  Dmitrii Dolgov <[email protected]>
  0 siblings, 0 replies; 9+ messages in thread

From: Dmitrii Dolgov @ 2024-01-22 20:20 UTC (permalink / raw)

Using query_id_const_merge only first/last element in an ArrayExpr will
be used to compute query id. Extend this to take into account number of
elements, and merge constants into groups based on it. Resulting groups
are powers of 10, i.e. 1 to 9, 10 to 99, etc.
---
 .../pg_stat_statements/expected/merging.out   | 84 +++++++++++++++----
 .../pg_stat_statements/pg_stat_statements.c   | 17 +++-
 contrib/pg_stat_statements/sql/merging.sql    | 13 +++
 doc/src/sgml/pgstatstatements.sgml            | 11 +--
 src/backend/nodes/queryjumblefuncs.c          | 52 ++++++++----
 src/include/nodes/queryjumble.h               |  7 +-
 6 files changed, 142 insertions(+), 42 deletions(-)

diff --git a/contrib/pg_stat_statements/expected/merging.out b/contrib/pg_stat_statements/expected/merging.out
index 1e58283afe8..0cb4f67b8b7 100644
--- a/contrib/pg_stat_statements/expected/merging.out
+++ b/contrib/pg_stat_statements/expected/merging.out
@@ -54,11 +54,11 @@ SELECT * FROM test_merge WHERE id IN (1, 2, 3);
 (0 rows)
 
 SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
-                       query                        | calls 
-----------------------------------------------------+-------
- SELECT * FROM test_merge WHERE id IN ($1)          |     1
- SELECT * FROM test_merge WHERE id IN (...)         |     1
- SELECT pg_stat_statements_reset() IS NOT NULL AS t |     1
+                          query                           | calls 
+----------------------------------------------------------+-------
+ SELECT * FROM test_merge WHERE id IN ($1)                |     1
+ SELECT * FROM test_merge WHERE id IN (... [1-9 entries]) |     1
+ SELECT pg_stat_statements_reset() IS NOT NULL AS t       |     1
 (3 rows)
 
 SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9);
@@ -80,7 +80,60 @@ SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
                                  query                                  | calls 
 ------------------------------------------------------------------------+-------
  SELECT * FROM test_merge WHERE id IN ($1)                              |     1
- SELECT * FROM test_merge WHERE id IN (...)                             |     4
+ SELECT * FROM test_merge WHERE id IN (... [1-9 entries])               |     2
+ SELECT * FROM test_merge WHERE id IN (... [10-99 entries])             |     2
+ SELECT pg_stat_statements_reset() IS NOT NULL AS t                     |     1
+ SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C" |     1
+(5 rows)
+
+-- Second order of magnitude, brace yourself
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110);
+ id | data 
+----+------
+(0 rows)
+
+SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
+                            query                             | calls 
+--------------------------------------------------------------+-------
+ SELECT * FROM test_merge WHERE id IN (... [100-999 entries]) |     1
+ SELECT pg_stat_statements_reset() IS NOT NULL AS t           |     1
+(2 rows)
+
+-- With gaps on the threshold
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4);
+ id | data 
+----+------
+(0 rows)
+
+SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
+                          query                           | calls 
+----------------------------------------------------------+-------
+ SELECT * FROM test_merge WHERE id IN (... [1-9 entries]) |     1
+ SELECT pg_stat_statements_reset() IS NOT NULL AS t       |     1
+(2 rows)
+
+SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15);
+ id | data 
+----+------
+(0 rows)
+
+SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
+                                 query                                  | calls 
+------------------------------------------------------------------------+-------
+ SELECT * FROM test_merge WHERE id IN (... [1-9 entries])               |     1
+ SELECT * FROM test_merge WHERE id IN (... [10-99 entries])             |     1
  SELECT pg_stat_statements_reset() IS NOT NULL AS t                     |     1
  SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C" |     1
 (4 rows)
@@ -108,11 +161,12 @@ SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11) and dat
 (0 rows)
 
 SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
-                          query                           | calls 
-----------------------------------------------------------+-------
- SELECT * FROM test_merge WHERE id IN (...) and data = $3 |     3
- SELECT pg_stat_statements_reset() IS NOT NULL AS t       |     1
-(2 rows)
+                                  query                                   | calls 
+--------------------------------------------------------------------------+-------
+ SELECT * FROM test_merge WHERE id IN (... [1-9 entries]) and data = $3   |     1
+ SELECT * FROM test_merge WHERE id IN (... [10-99 entries]) and data = $3 |     2
+ SELECT pg_stat_statements_reset() IS NOT NULL AS t                       |     1
+(3 rows)
 
 -- No constants simplification
 SELECT pg_stat_statements_reset() IS NOT NULL AS t;
@@ -147,10 +201,10 @@ SELECT * FROM test_merge_numeric WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
 (0 rows)
 
 SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
-                       query                        | calls 
-----------------------------------------------------+-------
- SELECT * FROM test_merge_numeric WHERE id IN (...) |     1
- SELECT pg_stat_statements_reset() IS NOT NULL AS t |     1
+                               query                                | calls 
+--------------------------------------------------------------------+-------
+ SELECT * FROM test_merge_numeric WHERE id IN (... [10-99 entries]) |     1
+ SELECT pg_stat_statements_reset() IS NOT NULL AS t                 |     1
 (2 rows)
 
 -- Test constants evaluation, verifies a tricky part to make sure there are no
diff --git a/contrib/pg_stat_statements/pg_stat_statements.c b/contrib/pg_stat_statements/pg_stat_statements.c
index 09912f61b7d..bb8c1894e05 100644
--- a/contrib/pg_stat_statements/pg_stat_statements.c
+++ b/contrib/pg_stat_statements/pg_stat_statements.c
@@ -2826,6 +2826,8 @@ generate_normalized_query(JumbleState *jstate, const char *query,
 				last_tok_len = 0;	/* Length (in bytes) of that tok */
 	bool		skip = false; 	/* Signals that certain constants are
 								   merged together and have to be skipped */
+	int 		magnitude; 		/* Order of magnitute for number of merged
+								   constants */
 
 
 	/*
@@ -2866,7 +2868,8 @@ generate_normalized_query(JumbleState *jstate, const char *query,
 		Assert(len_to_wrt >= 0);
 
 		/* Normal path, non merged constant */
-		if (!jstate->clocations[i].merged)
+		magnitude = jstate->clocations[i].magnitude;
+		if (magnitude == 0)
 		{
 			memcpy(norm_query + n_quer_loc, query + quer_loc, len_to_wrt);
 			n_quer_loc += len_to_wrt;
@@ -2882,12 +2885,22 @@ generate_normalized_query(JumbleState *jstate, const char *query,
 		/* The firsts merged constant */
 		else if (!skip)
 		{
+			static const uint32 powers_of_ten[] = {
+				1, 10, 100,
+				1000, 10000, 100000,
+				1000000, 10000000, 100000000,
+				1000000000
+			};
+			int lower_merged = powers_of_ten[magnitude - 1];
+			int upper_merged = powers_of_ten[magnitude];
+
 			memcpy(norm_query + n_quer_loc, query + quer_loc, len_to_wrt);
 			n_quer_loc += len_to_wrt;
 
 			/* Skip the following until a non merged constant appear */
 			skip = true;
-			n_quer_loc += sprintf(norm_query + n_quer_loc, "...");
+			n_quer_loc += sprintf(norm_query + n_quer_loc, "... [%d-%d entries]",
+								  lower_merged, upper_merged - 1);
 		}
 		/* Otherwise the constant is merged away */
 
diff --git a/contrib/pg_stat_statements/sql/merging.sql b/contrib/pg_stat_statements/sql/merging.sql
index 71985bb1cd9..657044faded 100644
--- a/contrib/pg_stat_statements/sql/merging.sql
+++ b/contrib/pg_stat_statements/sql/merging.sql
@@ -27,6 +27,19 @@ SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10);
 SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11);
 SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
 
+-- Second order of magnitude, brace yourself
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110);
+SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
+
+-- With gaps on the threshold
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4);
+SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
+
+SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15);
+SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
+
 -- More conditions in the query
 SELECT pg_stat_statements_reset() IS NOT NULL AS t;
 
diff --git a/doc/src/sgml/pgstatstatements.sgml b/doc/src/sgml/pgstatstatements.sgml
index 2b4c142f647..bac029430be 100644
--- a/doc/src/sgml/pgstatstatements.sgml
+++ b/doc/src/sgml/pgstatstatements.sgml
@@ -616,7 +616,7 @@
 =# SELECT * FROM test WHERE a IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12);
 =# SELECT query, calls FROM pg_stat_statements;
 -[ RECORD 1 ]------------------------------
-query | SELECT * FROM test WHERE a IN (...)
+query | SELECT * FROM test WHERE a IN (... [10-99 entries])
 calls | 2
 -[ RECORD 2 ]------------------------------
 query | SELECT pg_stat_statements_reset()
@@ -968,10 +968,11 @@ calls | 1
       with an array of different lenght.
 
       If this parameter is on, an array of constants will contribute only the
-      first and the last elements to the query identifier. It means two
-      occurences of the same query, where the only difference is number of
-      constants in the array, are going to get the same query identifier.
-      Such queries are represented in form <literal>'(...)'</literal>.
+      first element, the last element and the number of elements to the query
+      identifier. It means two occurences of the same query, where the only
+      difference is number of constants in the array, are going to get the
+      same query identifier if the arrays are of similar length.
+      Such queries are represented in form <literal>'(... [10-99 entries])'</literal>.
 
       The parameter could be used to reduce amount of repeating data stored
       via <structname>pg_stat_statements</structname>.  The default value is off.
diff --git a/src/backend/nodes/queryjumblefuncs.c b/src/backend/nodes/queryjumblefuncs.c
index 45717553b5b..7db7ae7f2ee 100644
--- a/src/backend/nodes/queryjumblefuncs.c
+++ b/src/backend/nodes/queryjumblefuncs.c
@@ -37,6 +37,8 @@
 #include "nodes/queryjumble.h"
 #include "parser/scansup.h"
 
+#include "utils/numutils.h"
+
 #define JUMBLE_SIZE				1024	/* query serialization buffer size */
 
 /* GUC parameters */
@@ -51,7 +53,7 @@ bool		query_id_enabled = false;
 static void AppendJumble(JumbleState *jstate,
 						 const unsigned char *item, Size size);
 static void RecordConstLocation(JumbleState *jstate,
-								int location, bool merged);
+								int location, int magnitude);
 static void _jumbleNode(JumbleState *jstate, Node *node);
 static void _jumbleElements(JumbleState *jstate, List *elements);
 static void _jumbleA_Const(JumbleState *jstate, Node *node);
@@ -206,12 +208,15 @@ AppendJumble(JumbleState *jstate, const unsigned char *item, Size size)
  * Record location of constant within query string of query tree that is
  * currently being walked.
  *
- * Merged argument signals that the constant represents the first or the last
- * element in a series of merged constants, and everything but the first/last
- * element contributes nothing to the jumble hash.
+ * Magnitude argument larger than zero signals that the constant represents the
+ * first or the last element in a series of merged constants, and everything
+ * but such first/last element will contribute nothing to the jumble hash. The
+ * magnitute value specifies order of magnitute (i.e. how many digits it has)
+ * for the number of elements in the series, to represent the fact of merging
+ * later on.
  */
 static void
-RecordConstLocation(JumbleState *jstate, int location, bool merged)
+RecordConstLocation(JumbleState *jstate, int location, int magnitude)
 {
 	/* -1 indicates unknown or undefined location */
 	if (location >= 0)
@@ -227,7 +232,7 @@ RecordConstLocation(JumbleState *jstate, int location, bool merged)
 		}
 		jstate->clocations[jstate->clocations_count].location = location;
 		/* initialize lengths to -1 to simplify third-party module usage */
-		jstate->clocations[jstate->clocations_count].merged = merged;
+		jstate->clocations[jstate->clocations_count].magnitude = magnitude;
 		jstate->clocations[jstate->clocations_count].length = -1;
 		jstate->clocations_count++;
 	}
@@ -237,24 +242,26 @@ RecordConstLocation(JumbleState *jstate, int location, bool merged)
  * Verify if the provided list contains could be merged down, which means it
  * contains only constant expressions.
  *
- * Return value indicates if merging is possible.
+ * Return value is the order of magnitude (i.e. how many digits it has) for
+ * length of the list (to use for representation purposes later on) if merging
+ * is possible, otherwise zero.
  *
  * Note that this function searches only for explicit Const nodes and does not
  * try to simplify expressions.
  */
-static bool
+static int
 IsMergeableConstList(List *elements, Const **firstConst, Const **lastConst)
 {
 	ListCell   *temp;
 	Node	   *firstExpr = NULL;
 
 	if (elements == NULL)
-		return false;
+		return 0;
 
 	if (!query_id_const_merge)
 	{
 		/* Merging is disabled, process everything one by one */
-		return false;
+		return 0;
 	}
 
 	firstExpr = linitial(elements);
@@ -268,26 +275,26 @@ IsMergeableConstList(List *elements, Const **firstConst, Const **lastConst)
 	{
 		foreach(temp, elements)
 			if (!IsA(lfirst(temp), Const))
-				return false;
+				return 0;
 
 		*firstConst = (Const *) firstExpr;
 		*lastConst = llast_node(Const, elements);
-		return true;
+		return decimalLength32(elements->length);
 	}
 
 	/*
 	 * If we end up here, it means no constants merging is possible, process
 	 * the list as usual.
 	 */
-	return false;
+	return 0;
 }
 
 #define JUMBLE_NODE(item) \
 	_jumbleNode(jstate, (Node *) expr->item)
 #define JUMBLE_ELEMENTS(list) \
 	_jumbleElements(jstate, (List *) expr->list)
-#define JUMBLE_LOCATION(location, merged) \
-	RecordConstLocation(jstate, expr->location, merged)
+#define JUMBLE_LOCATION(location, magnitude) \
+	RecordConstLocation(jstate, expr->location, magnitude)
 #define JUMBLE_FIELD(item) \
 	AppendJumble(jstate, (const unsigned char *) &(expr->item), sizeof(expr->item))
 #define JUMBLE_FIELD_SINGLE(item) \
@@ -304,10 +311,19 @@ static void
 _jumbleElements(JumbleState *jstate, List *elements)
 {
 	Const *first, *last;
-	if(IsMergeableConstList(elements, &first, &last))
+	int magnitude = IsMergeableConstList(elements, &first, &last);
+
+	if (magnitude)
 	{
-		RecordConstLocation(jstate, first->location, true);
-		RecordConstLocation(jstate, last->location, true);
+		RecordConstLocation(jstate, first->location, magnitude);
+		RecordConstLocation(jstate, last->location, magnitude);
+
+		/*
+		 * After merging constants down we end up with only two constants, the
+		 * first and the last one. To distinguish the order of magnitute behind
+		 * merged constants, add its value into the jumble.
+		 */
+		JUMBLE_FIELD_SINGLE(magnitude);
 	}
 	else
 	{
diff --git a/src/include/nodes/queryjumble.h b/src/include/nodes/queryjumble.h
index 8daf0725d7f..551555494e0 100644
--- a/src/include/nodes/queryjumble.h
+++ b/src/include/nodes/queryjumble.h
@@ -26,9 +26,12 @@ typedef struct LocationLen
 
 	/*
 	 * Indicates the constant represents the beginning or the end of a merged
-	 * constants interval.
+	 * constants interval. The value shows how many constants were merged away
+	 * (up to a power of 10), or in other words the order of manitude for
+	 * number of merged constants (i.e. how many digits it has). Otherwise the
+	 * value is 0, indicating that no merging was performed.
 	 */
-	bool		merged;
+	int			magnitude;
 } LocationLen;
 
 /*
-- 
2.41.0


--tp75mykizkxh6a6a
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
	filename="v18-0004-Introduce-query_id_const_merge_threshold.patch"



^ permalink  raw  reply  [nested|flat] 9+ messages in thread

* [PATCH v22 3/4] Merge constants in ArrayExpr into groups
@ 2024-05-12 09:51  Dmitrii Dolgov <[email protected]>
  0 siblings, 0 replies; 9+ messages in thread

From: Dmitrii Dolgov @ 2024-05-12 09:51 UTC (permalink / raw)

Using query_id_const_merge only first/last element in an ArrayExpr will
be used to compute query id. Extend this to take into account number of
elements, and merge constants into groups based on it. Resulting groups
are powers of 10, i.e. 1 to 9, 10 to 99, etc.

Reviewed-by: Sutou Kouhei
Tested-by: Yasuo Honda
---
 .../pg_stat_statements/expected/merging.out   | 84 +++++++++++++++----
 .../pg_stat_statements/pg_stat_statements.c   | 29 +++++--
 contrib/pg_stat_statements/sql/merging.sql    | 13 +++
 doc/src/sgml/pgstatstatements.sgml            | 11 +--
 src/backend/nodes/gen_node_support.pl         |  2 +-
 src/backend/nodes/queryjumblefuncs.c          | 55 ++++++++----
 src/include/nodes/queryjumble.h               | 10 ++-
 7 files changed, 158 insertions(+), 46 deletions(-)

diff --git a/contrib/pg_stat_statements/expected/merging.out b/contrib/pg_stat_statements/expected/merging.out
index 1e58283afe..0cb4f67b8b 100644
--- a/contrib/pg_stat_statements/expected/merging.out
+++ b/contrib/pg_stat_statements/expected/merging.out
@@ -54,11 +54,11 @@ SELECT * FROM test_merge WHERE id IN (1, 2, 3);
 (0 rows)
 
 SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
-                       query                        | calls 
-----------------------------------------------------+-------
- SELECT * FROM test_merge WHERE id IN ($1)          |     1
- SELECT * FROM test_merge WHERE id IN (...)         |     1
- SELECT pg_stat_statements_reset() IS NOT NULL AS t |     1
+                          query                           | calls 
+----------------------------------------------------------+-------
+ SELECT * FROM test_merge WHERE id IN ($1)                |     1
+ SELECT * FROM test_merge WHERE id IN (... [1-9 entries]) |     1
+ SELECT pg_stat_statements_reset() IS NOT NULL AS t       |     1
 (3 rows)
 
 SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9);
@@ -80,7 +80,60 @@ SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
                                  query                                  | calls 
 ------------------------------------------------------------------------+-------
  SELECT * FROM test_merge WHERE id IN ($1)                              |     1
- SELECT * FROM test_merge WHERE id IN (...)                             |     4
+ SELECT * FROM test_merge WHERE id IN (... [1-9 entries])               |     2
+ SELECT * FROM test_merge WHERE id IN (... [10-99 entries])             |     2
+ SELECT pg_stat_statements_reset() IS NOT NULL AS t                     |     1
+ SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C" |     1
+(5 rows)
+
+-- Second order of magnitude, brace yourself
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110);
+ id | data 
+----+------
+(0 rows)
+
+SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
+                            query                             | calls 
+--------------------------------------------------------------+-------
+ SELECT * FROM test_merge WHERE id IN (... [100-999 entries]) |     1
+ SELECT pg_stat_statements_reset() IS NOT NULL AS t           |     1
+(2 rows)
+
+-- With gaps on the threshold
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4);
+ id | data 
+----+------
+(0 rows)
+
+SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
+                          query                           | calls 
+----------------------------------------------------------+-------
+ SELECT * FROM test_merge WHERE id IN (... [1-9 entries]) |     1
+ SELECT pg_stat_statements_reset() IS NOT NULL AS t       |     1
+(2 rows)
+
+SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15);
+ id | data 
+----+------
+(0 rows)
+
+SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
+                                 query                                  | calls 
+------------------------------------------------------------------------+-------
+ SELECT * FROM test_merge WHERE id IN (... [1-9 entries])               |     1
+ SELECT * FROM test_merge WHERE id IN (... [10-99 entries])             |     1
  SELECT pg_stat_statements_reset() IS NOT NULL AS t                     |     1
  SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C" |     1
 (4 rows)
@@ -108,11 +161,12 @@ SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11) and dat
 (0 rows)
 
 SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
-                          query                           | calls 
-----------------------------------------------------------+-------
- SELECT * FROM test_merge WHERE id IN (...) and data = $3 |     3
- SELECT pg_stat_statements_reset() IS NOT NULL AS t       |     1
-(2 rows)
+                                  query                                   | calls 
+--------------------------------------------------------------------------+-------
+ SELECT * FROM test_merge WHERE id IN (... [1-9 entries]) and data = $3   |     1
+ SELECT * FROM test_merge WHERE id IN (... [10-99 entries]) and data = $3 |     2
+ SELECT pg_stat_statements_reset() IS NOT NULL AS t                       |     1
+(3 rows)
 
 -- No constants simplification
 SELECT pg_stat_statements_reset() IS NOT NULL AS t;
@@ -147,10 +201,10 @@ SELECT * FROM test_merge_numeric WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
 (0 rows)
 
 SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
-                       query                        | calls 
-----------------------------------------------------+-------
- SELECT * FROM test_merge_numeric WHERE id IN (...) |     1
- SELECT pg_stat_statements_reset() IS NOT NULL AS t |     1
+                               query                                | calls 
+--------------------------------------------------------------------+-------
+ SELECT * FROM test_merge_numeric WHERE id IN (... [10-99 entries]) |     1
+ SELECT pg_stat_statements_reset() IS NOT NULL AS t                 |     1
 (2 rows)
 
 -- Test constants evaluation, verifies a tricky part to make sure there are no
diff --git a/contrib/pg_stat_statements/pg_stat_statements.c b/contrib/pg_stat_statements/pg_stat_statements.c
index bcbf1164c1..24ab2a45ff 100644
--- a/contrib/pg_stat_statements/pg_stat_statements.c
+++ b/contrib/pg_stat_statements/pg_stat_statements.c
@@ -2830,6 +2830,8 @@ generate_normalized_query(JumbleState *jstate, const char *query,
 	bool		merged_interval = false;	/* Currently processed constants
 											   belong to a merged constants
 											   interval. */
+	int 		magnitude; 		/* Order of magnitute for number of merged
+								   constants */
 
 
 	/*
@@ -2844,8 +2846,13 @@ generate_normalized_query(JumbleState *jstate, const char *query,
 	 * certainly isn't more than 11 bytes, even if n reaches INT_MAX.  We
 	 * could refine that limit based on the max value of n for the current
 	 * query, but it hardly seems worth any extra effort to do so.
+	 *
+	 * On top of that, each pair of $n symbols representing a merged constants
+	 * interval will be decorated with the explanationary text, adding 14
+	 * bytes.
 	 */
-	norm_query_buflen = query_len + jstate->clocations_count * 10;
+	norm_query_buflen = query_len + jstate->clocations_count * 10 +
+		jstate->clocations_merged_count * 14;
 
 	/* Allocate result buffer */
 	norm_query = palloc(norm_query_buflen + 1);
@@ -2870,7 +2877,8 @@ generate_normalized_query(JumbleState *jstate, const char *query,
 		Assert(len_to_wrt >= 0);
 
 		/* Normal path, non merged constant */
-		if (!jstate->clocations[i].merged)
+		magnitude = jstate->clocations[i].magnitude;
+		if (magnitude == 0)
 		{
 			memcpy(norm_query + n_quer_loc, query + quer_loc, len_to_wrt);
 			n_quer_loc += len_to_wrt;
@@ -2887,13 +2895,23 @@ generate_normalized_query(JumbleState *jstate, const char *query,
 			/*
 			 * We are not inside a merged interval yet, which means it is the
 			 * the first merged constant.
-			 *
+			 */
+			static const uint32 powers_of_ten[] = {
+				1, 10, 100,
+				1000, 10000, 100000,
+				1000000, 10000000, 100000000,
+				1000000000
+			};
+			int lower_merged = powers_of_ten[magnitude - 1];
+			int upper_merged = powers_of_ten[magnitude];
+
+			/*
 			 * A merged constants interval must be represented via two
 			 * constants with the merged flag. Currently we are at the first,
 			 * verify there is another one.
 			 */
 			Assert(i + 1 < jstate->clocations_count);
-			Assert(jstate->clocations[i + 1].merged);
+			Assert(jstate->clocations[i + 1].magnitude > 0);
 
 			memcpy(norm_query + n_quer_loc, query + quer_loc, len_to_wrt);
 			n_quer_loc += len_to_wrt;
@@ -2902,7 +2920,8 @@ generate_normalized_query(JumbleState *jstate, const char *query,
 			merged_interval = true;
 
 			/* Mark the interval in the normalized query */
-			n_quer_loc += sprintf(norm_query + n_quer_loc, "...");
+			n_quer_loc += sprintf(norm_query + n_quer_loc, "... [%d-%d entries]",
+								  lower_merged, upper_merged - 1);
 		}
 
 		/* Otherwise the constant is merged away, move forward */
diff --git a/contrib/pg_stat_statements/sql/merging.sql b/contrib/pg_stat_statements/sql/merging.sql
index 71985bb1cd..657044fade 100644
--- a/contrib/pg_stat_statements/sql/merging.sql
+++ b/contrib/pg_stat_statements/sql/merging.sql
@@ -27,6 +27,19 @@ SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10);
 SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11);
 SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
 
+-- Second order of magnitude, brace yourself
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110);
+SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
+
+-- With gaps on the threshold
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4);
+SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
+
+SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15);
+SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
+
 -- More conditions in the query
 SELECT pg_stat_statements_reset() IS NOT NULL AS t;
 
diff --git a/doc/src/sgml/pgstatstatements.sgml b/doc/src/sgml/pgstatstatements.sgml
index 2276783786..55dfa5b50f 100644
--- a/doc/src/sgml/pgstatstatements.sgml
+++ b/doc/src/sgml/pgstatstatements.sgml
@@ -634,7 +634,7 @@
 =# SELECT * FROM test WHERE a IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12);
 =# SELECT query, calls FROM pg_stat_statements;
 -[ RECORD 1 ]------------------------------
-query | SELECT * FROM test WHERE a IN (...)
+query | SELECT * FROM test WHERE a IN (... [10-99 entries])
 calls | 2
 -[ RECORD 2 ]------------------------------
 query | SELECT pg_stat_statements_reset()
@@ -992,10 +992,11 @@ calls | 1
       with an array of different lenght.
 
       If this parameter is on, an array of constants will contribute only the
-      first and the last elements to the query identifier. It means two
-      occurences of the same query, where the only difference is number of
-      constants in the array, are going to get the same query identifier.
-      Such queries are represented in form <literal>'(...)'</literal>.
+      first element, the last element and the number of elements to the query
+      identifier. It means two occurences of the same query, where the only
+      difference is number of constants in the array, are going to get the
+      same query identifier if the arrays are of similar length.
+      Such queries are represented in form <literal>'(... [10-99 entries])'</literal>.
 
       The parameter could be used to reduce amount of repeating data stored
       via <structname>pg_stat_statements</structname>.  The default value is off.
diff --git a/src/backend/nodes/gen_node_support.pl b/src/backend/nodes/gen_node_support.pl
index d2a276c303..c98d121dba 100644
--- a/src/backend/nodes/gen_node_support.pl
+++ b/src/backend/nodes/gen_node_support.pl
@@ -1323,7 +1323,7 @@ _jumble${n}(JumbleState *jstate, Node *node)
 			# Track the node's location only if directly requested.
 			if ($query_jumble_location)
 			{
-				print $jff "\tJUMBLE_LOCATION($f, false);\n"
+				print $jff "\tJUMBLE_LOCATION($f, 0);\n"
 				  unless $query_jumble_ignore;
 			}
 		}
diff --git a/src/backend/nodes/queryjumblefuncs.c b/src/backend/nodes/queryjumblefuncs.c
index 2953073872..8ab3261d66 100644
--- a/src/backend/nodes/queryjumblefuncs.c
+++ b/src/backend/nodes/queryjumblefuncs.c
@@ -37,6 +37,8 @@
 #include "nodes/queryjumble.h"
 #include "parser/scansup.h"
 
+#include "utils/numutils.h"
+
 #define JUMBLE_SIZE				1024	/* query serialization buffer size */
 
 /* GUC parameters */
@@ -57,7 +59,7 @@ bool		query_id_enabled = false;
 static void AppendJumble(JumbleState *jstate,
 						 const unsigned char *item, Size size);
 static void RecordConstLocation(JumbleState *jstate,
-								int location, bool merged);
+								int location, int magnitude);
 static void _jumbleNode(JumbleState *jstate, Node *node);
 static void _jumbleElements(JumbleState *jstate, List *elements);
 static void _jumbleA_Const(JumbleState *jstate, Node *node);
@@ -129,6 +131,7 @@ JumbleQuery(Query *query)
 	jstate->clocations = (LocationLen *)
 		palloc(jstate->clocations_buf_size * sizeof(LocationLen));
 	jstate->clocations_count = 0;
+	jstate->clocations_merged_count = 0;
 	jstate->highest_extern_param_id = 0;
 
 	/* Compute query ID and mark the Query node with it */
@@ -218,12 +221,15 @@ AppendJumble(JumbleState *jstate, const unsigned char *item, Size size)
  * Record location of constant within query string of query tree that is
  * currently being walked.
  *
- * Merged argument signals that the constant represents the first or the last
- * element in a series of merged constants, and everything but the first/last
- * element contributes nothing to the jumble hash.
+ * Magnitude argument larger than zero signals that the constant represents the
+ * first or the last element in a series of merged constants, and everything
+ * but such first/last element will contribute nothing to the jumble hash. The
+ * magnitute value specifies order of magnitute (i.e. how many digits it has)
+ * for the number of elements in the series, to represent the fact of merging
+ * later on.
  */
 static void
-RecordConstLocation(JumbleState *jstate, int location, bool merged)
+RecordConstLocation(JumbleState *jstate, int location, int magnitude)
 {
 	/* -1 indicates unknown or undefined location */
 	if (location >= 0)
@@ -238,10 +244,12 @@ RecordConstLocation(JumbleState *jstate, int location, bool merged)
 						 sizeof(LocationLen));
 		}
 		jstate->clocations[jstate->clocations_count].location = location;
+		jstate->clocations[jstate->clocations_count].magnitude = magnitude;
 		/* initialize lengths to -1 to simplify third-party module usage */
-		jstate->clocations[jstate->clocations_count].merged = merged;
 		jstate->clocations[jstate->clocations_count].length = -1;
 		jstate->clocations_count++;
+		if (magnitude > 0)
+			jstate->clocations_merged_count++;
 	}
 }
 
@@ -249,24 +257,26 @@ RecordConstLocation(JumbleState *jstate, int location, bool merged)
  * Verify if the provided list contains could be merged down, which means it
  * contains only constant expressions.
  *
- * Return value indicates if merging is possible.
+ * Return value is the order of magnitude (i.e. how many digits it has) for
+ * length of the list (to use for representation purposes later on) if merging
+ * is possible, otherwise zero.
  *
  * Note that this function searches only for explicit Const nodes and does not
  * try to simplify expressions.
  */
-static bool
+static int
 IsMergeableConstList(List *elements, Const **firstConst, Const **lastConst)
 {
 	ListCell   *temp;
 	Node	   *firstExpr = NULL;
 
 	if (elements == NIL)
-		return false;
+		return 0;
 
 	if (!query_id_const_merge)
 	{
 		/* Merging is disabled, process everything one by one */
-		return false;
+		return 0;
 	}
 
 	firstExpr = linitial(elements);
@@ -280,26 +290,26 @@ IsMergeableConstList(List *elements, Const **firstConst, Const **lastConst)
 	{
 		foreach(temp, elements)
 			if (!IsA(lfirst(temp), Const))
-				return false;
+				return 0;
 
 		*firstConst = (Const *) firstExpr;
 		*lastConst = llast_node(Const, elements);
-		return true;
+		return decimalLength32(elements->length);
 	}
 
 	/*
 	 * If we end up here, it means no constants merging is possible, process
 	 * the list as usual.
 	 */
-	return false;
+	return 0;
 }
 
 #define JUMBLE_NODE(item) \
 	_jumbleNode(jstate, (Node *) expr->item)
 #define JUMBLE_ELEMENTS(list) \
 	_jumbleElements(jstate, (List *) expr->list)
-#define JUMBLE_LOCATION(location, merged) \
-	RecordConstLocation(jstate, expr->location, merged)
+#define JUMBLE_LOCATION(location, magnitude) \
+	RecordConstLocation(jstate, expr->location, magnitude)
 #define JUMBLE_FIELD(item) \
 	AppendJumble(jstate, (const unsigned char *) &(expr->item), sizeof(expr->item))
 #define JUMBLE_FIELD_SINGLE(item) \
@@ -316,15 +326,24 @@ static void
 _jumbleElements(JumbleState *jstate, List *elements)
 {
 	Const *first, *last;
-	if (IsMergeableConstList(elements, &first, &last))
+	int magnitude = IsMergeableConstList(elements, &first, &last);
+
+	if (magnitude)
 	{
 		/*
 		 * Both first and last constants have to be recorded. The first one
 		 * will indicate the merged interval, the last one will tell us the
 		 * length of the interval within the query text.
 		 */
-		RecordConstLocation(jstate, first->location, true);
-		RecordConstLocation(jstate, last->location, true);
+		RecordConstLocation(jstate, first->location, magnitude);
+		RecordConstLocation(jstate, last->location, magnitude);
+
+		/*
+		 * After merging constants down we end up with only two constants, the
+		 * first and the last one. To distinguish the order of magnitute behind
+		 * merged constants, add its value into the jumble.
+		 */
+		JUMBLE_FIELD_SINGLE(magnitude);
 	}
 	else
 	{
diff --git a/src/include/nodes/queryjumble.h b/src/include/nodes/queryjumble.h
index 8daf0725d7..0e69e420b7 100644
--- a/src/include/nodes/queryjumble.h
+++ b/src/include/nodes/queryjumble.h
@@ -26,9 +26,12 @@ typedef struct LocationLen
 
 	/*
 	 * Indicates the constant represents the beginning or the end of a merged
-	 * constants interval.
+	 * constants interval. The value shows how many constants were merged away
+	 * (up to a power of 10), or in other words the order of manitude for
+	 * number of merged constants (i.e. how many digits it has). Otherwise the
+	 * value is 0, indicating that no merging was performed.
 	 */
-	bool		merged;
+	int			magnitude;
 } LocationLen;
 
 /*
@@ -52,6 +55,9 @@ typedef struct JumbleState
 	/* Current number of valid entries in clocations array */
 	int			clocations_count;
 
+	/* Current number of entries with merged constants interval */
+	int			clocations_merged_count;
+
 	/* highest Param id we've seen, in order to start normalization correctly */
 	int			highest_extern_param_id;
 } JumbleState;
-- 
2.45.1


--nse6ci3hmyxhp7l3
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename="v22-0004-Introduce-query_id_const_merge_threshold.patch"



^ permalink  raw  reply  [nested|flat] 9+ messages in thread

* [PATCH v21 3/4] Merge constants in ArrayExpr into groups
@ 2024-05-12 09:51  Dmitrii Dolgov <[email protected]>
  0 siblings, 0 replies; 9+ messages in thread

From: Dmitrii Dolgov @ 2024-05-12 09:51 UTC (permalink / raw)

Using query_id_const_merge only first/last element in an ArrayExpr will
be used to compute query id. Extend this to take into account number of
elements, and merge constants into groups based on it. Resulting groups
are powers of 10, i.e. 1 to 9, 10 to 99, etc.

Reviewed-by: Sutou Kouhei
Tested-by: Yasuo Honda
---
 .../pg_stat_statements/expected/merging.out   | 84 +++++++++++++++----
 .../pg_stat_statements/pg_stat_statements.c   | 29 +++++--
 contrib/pg_stat_statements/sql/merging.sql    | 13 +++
 doc/src/sgml/pgstatstatements.sgml            | 11 +--
 src/backend/nodes/queryjumblefuncs.c          | 55 ++++++++----
 src/include/nodes/queryjumble.h               | 10 ++-
 6 files changed, 157 insertions(+), 45 deletions(-)

diff --git a/contrib/pg_stat_statements/expected/merging.out b/contrib/pg_stat_statements/expected/merging.out
index 1e58283afe..0cb4f67b8b 100644
--- a/contrib/pg_stat_statements/expected/merging.out
+++ b/contrib/pg_stat_statements/expected/merging.out
@@ -54,11 +54,11 @@ SELECT * FROM test_merge WHERE id IN (1, 2, 3);
 (0 rows)
 
 SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
-                       query                        | calls 
-----------------------------------------------------+-------
- SELECT * FROM test_merge WHERE id IN ($1)          |     1
- SELECT * FROM test_merge WHERE id IN (...)         |     1
- SELECT pg_stat_statements_reset() IS NOT NULL AS t |     1
+                          query                           | calls 
+----------------------------------------------------------+-------
+ SELECT * FROM test_merge WHERE id IN ($1)                |     1
+ SELECT * FROM test_merge WHERE id IN (... [1-9 entries]) |     1
+ SELECT pg_stat_statements_reset() IS NOT NULL AS t       |     1
 (3 rows)
 
 SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9);
@@ -80,7 +80,60 @@ SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
                                  query                                  | calls 
 ------------------------------------------------------------------------+-------
  SELECT * FROM test_merge WHERE id IN ($1)                              |     1
- SELECT * FROM test_merge WHERE id IN (...)                             |     4
+ SELECT * FROM test_merge WHERE id IN (... [1-9 entries])               |     2
+ SELECT * FROM test_merge WHERE id IN (... [10-99 entries])             |     2
+ SELECT pg_stat_statements_reset() IS NOT NULL AS t                     |     1
+ SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C" |     1
+(5 rows)
+
+-- Second order of magnitude, brace yourself
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110);
+ id | data 
+----+------
+(0 rows)
+
+SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
+                            query                             | calls 
+--------------------------------------------------------------+-------
+ SELECT * FROM test_merge WHERE id IN (... [100-999 entries]) |     1
+ SELECT pg_stat_statements_reset() IS NOT NULL AS t           |     1
+(2 rows)
+
+-- With gaps on the threshold
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4);
+ id | data 
+----+------
+(0 rows)
+
+SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
+                          query                           | calls 
+----------------------------------------------------------+-------
+ SELECT * FROM test_merge WHERE id IN (... [1-9 entries]) |     1
+ SELECT pg_stat_statements_reset() IS NOT NULL AS t       |     1
+(2 rows)
+
+SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15);
+ id | data 
+----+------
+(0 rows)
+
+SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
+                                 query                                  | calls 
+------------------------------------------------------------------------+-------
+ SELECT * FROM test_merge WHERE id IN (... [1-9 entries])               |     1
+ SELECT * FROM test_merge WHERE id IN (... [10-99 entries])             |     1
  SELECT pg_stat_statements_reset() IS NOT NULL AS t                     |     1
  SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C" |     1
 (4 rows)
@@ -108,11 +161,12 @@ SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11) and dat
 (0 rows)
 
 SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
-                          query                           | calls 
-----------------------------------------------------------+-------
- SELECT * FROM test_merge WHERE id IN (...) and data = $3 |     3
- SELECT pg_stat_statements_reset() IS NOT NULL AS t       |     1
-(2 rows)
+                                  query                                   | calls 
+--------------------------------------------------------------------------+-------
+ SELECT * FROM test_merge WHERE id IN (... [1-9 entries]) and data = $3   |     1
+ SELECT * FROM test_merge WHERE id IN (... [10-99 entries]) and data = $3 |     2
+ SELECT pg_stat_statements_reset() IS NOT NULL AS t                       |     1
+(3 rows)
 
 -- No constants simplification
 SELECT pg_stat_statements_reset() IS NOT NULL AS t;
@@ -147,10 +201,10 @@ SELECT * FROM test_merge_numeric WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
 (0 rows)
 
 SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
-                       query                        | calls 
-----------------------------------------------------+-------
- SELECT * FROM test_merge_numeric WHERE id IN (...) |     1
- SELECT pg_stat_statements_reset() IS NOT NULL AS t |     1
+                               query                                | calls 
+--------------------------------------------------------------------+-------
+ SELECT * FROM test_merge_numeric WHERE id IN (... [10-99 entries]) |     1
+ SELECT pg_stat_statements_reset() IS NOT NULL AS t                 |     1
 (2 rows)
 
 -- Test constants evaluation, verifies a tricky part to make sure there are no
diff --git a/contrib/pg_stat_statements/pg_stat_statements.c b/contrib/pg_stat_statements/pg_stat_statements.c
index d267a72e0a..1c35e10117 100644
--- a/contrib/pg_stat_statements/pg_stat_statements.c
+++ b/contrib/pg_stat_statements/pg_stat_statements.c
@@ -2828,6 +2828,8 @@ generate_normalized_query(JumbleState *jstate, const char *query,
 	bool		merged_interval = false;	/* Currently processed constants
 											   belong to a merged constants
 											   interval. */
+	int 		magnitude; 		/* Order of magnitute for number of merged
+								   constants */
 
 
 	/*
@@ -2842,8 +2844,13 @@ generate_normalized_query(JumbleState *jstate, const char *query,
 	 * certainly isn't more than 11 bytes, even if n reaches INT_MAX.  We
 	 * could refine that limit based on the max value of n for the current
 	 * query, but it hardly seems worth any extra effort to do so.
+	 *
+	 * On top of that, each pair of $n symbols representing a merged constants
+	 * interval will be decorated with the explanationary text, adding 14
+	 * bytes.
 	 */
-	norm_query_buflen = query_len + jstate->clocations_count * 10;
+	norm_query_buflen = query_len + jstate->clocations_count * 10 +
+		jstate->clocations_merged_count * 14;
 
 	/* Allocate result buffer */
 	norm_query = palloc(norm_query_buflen + 1);
@@ -2868,7 +2875,8 @@ generate_normalized_query(JumbleState *jstate, const char *query,
 		Assert(len_to_wrt >= 0);
 
 		/* Normal path, non merged constant */
-		if (!jstate->clocations[i].merged)
+		magnitude = jstate->clocations[i].magnitude;
+		if (magnitude == 0)
 		{
 			memcpy(norm_query + n_quer_loc, query + quer_loc, len_to_wrt);
 			n_quer_loc += len_to_wrt;
@@ -2885,13 +2893,23 @@ generate_normalized_query(JumbleState *jstate, const char *query,
 			/*
 			 * We are not inside a merged interval yet, which means it is the
 			 * the first merged constant.
-			 *
+			 */
+			static const uint32 powers_of_ten[] = {
+				1, 10, 100,
+				1000, 10000, 100000,
+				1000000, 10000000, 100000000,
+				1000000000
+			};
+			int lower_merged = powers_of_ten[magnitude - 1];
+			int upper_merged = powers_of_ten[magnitude];
+
+			/*
 			 * A merged constants interval must be represented via two
 			 * constants with the merged flag. Currently we are at the first,
 			 * verify there is another one.
 			 */
 			Assert(i + 1 < jstate->clocations_count);
-			Assert(jstate->clocations[i + 1].merged);
+			Assert(jstate->clocations[i + 1].magnitude > 0);
 
 			memcpy(norm_query + n_quer_loc, query + quer_loc, len_to_wrt);
 			n_quer_loc += len_to_wrt;
@@ -2900,7 +2918,8 @@ generate_normalized_query(JumbleState *jstate, const char *query,
 			merged_interval = true;
 
 			/* Mark the interval in the normalized query */
-			n_quer_loc += sprintf(norm_query + n_quer_loc, "...");
+			n_quer_loc += sprintf(norm_query + n_quer_loc, "... [%d-%d entries]",
+								  lower_merged, upper_merged - 1);
 		}
 
 		/* Otherwise the constant is merged away, move forward */
diff --git a/contrib/pg_stat_statements/sql/merging.sql b/contrib/pg_stat_statements/sql/merging.sql
index 71985bb1cd..657044fade 100644
--- a/contrib/pg_stat_statements/sql/merging.sql
+++ b/contrib/pg_stat_statements/sql/merging.sql
@@ -27,6 +27,19 @@ SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10);
 SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11);
 SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
 
+-- Second order of magnitude, brace yourself
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110);
+SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
+
+-- With gaps on the threshold
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4);
+SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
+
+SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15);
+SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
+
 -- More conditions in the query
 SELECT pg_stat_statements_reset() IS NOT NULL AS t;
 
diff --git a/doc/src/sgml/pgstatstatements.sgml b/doc/src/sgml/pgstatstatements.sgml
index cbe1f3e171..12ffd02190 100644
--- a/doc/src/sgml/pgstatstatements.sgml
+++ b/doc/src/sgml/pgstatstatements.sgml
@@ -616,7 +616,7 @@
 =# SELECT * FROM test WHERE a IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12);
 =# SELECT query, calls FROM pg_stat_statements;
 -[ RECORD 1 ]------------------------------
-query | SELECT * FROM test WHERE a IN (...)
+query | SELECT * FROM test WHERE a IN (... [10-99 entries])
 calls | 2
 -[ RECORD 2 ]------------------------------
 query | SELECT pg_stat_statements_reset()
@@ -974,10 +974,11 @@ calls | 1
       with an array of different lenght.
 
       If this parameter is on, an array of constants will contribute only the
-      first and the last elements to the query identifier. It means two
-      occurences of the same query, where the only difference is number of
-      constants in the array, are going to get the same query identifier.
-      Such queries are represented in form <literal>'(...)'</literal>.
+      first element, the last element and the number of elements to the query
+      identifier. It means two occurences of the same query, where the only
+      difference is number of constants in the array, are going to get the
+      same query identifier if the arrays are of similar length.
+      Such queries are represented in form <literal>'(... [10-99 entries])'</literal>.
 
       The parameter could be used to reduce amount of repeating data stored
       via <structname>pg_stat_statements</structname>.  The default value is off.
diff --git a/src/backend/nodes/queryjumblefuncs.c b/src/backend/nodes/queryjumblefuncs.c
index 722b064873..1d3f36ca64 100644
--- a/src/backend/nodes/queryjumblefuncs.c
+++ b/src/backend/nodes/queryjumblefuncs.c
@@ -37,6 +37,8 @@
 #include "nodes/queryjumble.h"
 #include "parser/scansup.h"
 
+#include "utils/numutils.h"
+
 #define JUMBLE_SIZE				1024	/* query serialization buffer size */
 
 /* GUC parameters */
@@ -57,7 +59,7 @@ bool		query_id_enabled = false;
 static void AppendJumble(JumbleState *jstate,
 						 const unsigned char *item, Size size);
 static void RecordConstLocation(JumbleState *jstate,
-								int location, bool merged);
+								int location, int magnitude);
 static void _jumbleNode(JumbleState *jstate, Node *node);
 static void _jumbleElements(JumbleState *jstate, List *elements);
 static void _jumbleA_Const(JumbleState *jstate, Node *node);
@@ -122,6 +124,7 @@ JumbleQuery(Query *query)
 	jstate->clocations = (LocationLen *)
 		palloc(jstate->clocations_buf_size * sizeof(LocationLen));
 	jstate->clocations_count = 0;
+	jstate->clocations_merged_count = 0;
 	jstate->highest_extern_param_id = 0;
 
 	/* Compute query ID and mark the Query node with it */
@@ -211,12 +214,15 @@ AppendJumble(JumbleState *jstate, const unsigned char *item, Size size)
  * Record location of constant within query string of query tree that is
  * currently being walked.
  *
- * Merged argument signals that the constant represents the first or the last
- * element in a series of merged constants, and everything but the first/last
- * element contributes nothing to the jumble hash.
+ * Magnitude argument larger than zero signals that the constant represents the
+ * first or the last element in a series of merged constants, and everything
+ * but such first/last element will contribute nothing to the jumble hash. The
+ * magnitute value specifies order of magnitute (i.e. how many digits it has)
+ * for the number of elements in the series, to represent the fact of merging
+ * later on.
  */
 static void
-RecordConstLocation(JumbleState *jstate, int location, bool merged)
+RecordConstLocation(JumbleState *jstate, int location, int magnitude)
 {
 	/* -1 indicates unknown or undefined location */
 	if (location >= 0)
@@ -231,10 +237,12 @@ RecordConstLocation(JumbleState *jstate, int location, bool merged)
 						 sizeof(LocationLen));
 		}
 		jstate->clocations[jstate->clocations_count].location = location;
+		jstate->clocations[jstate->clocations_count].magnitude = magnitude;
 		/* initialize lengths to -1 to simplify third-party module usage */
-		jstate->clocations[jstate->clocations_count].merged = merged;
 		jstate->clocations[jstate->clocations_count].length = -1;
 		jstate->clocations_count++;
+		if (magnitude > 0)
+			jstate->clocations_merged_count++;
 	}
 }
 
@@ -242,24 +250,26 @@ RecordConstLocation(JumbleState *jstate, int location, bool merged)
  * Verify if the provided list contains could be merged down, which means it
  * contains only constant expressions.
  *
- * Return value indicates if merging is possible.
+ * Return value is the order of magnitude (i.e. how many digits it has) for
+ * length of the list (to use for representation purposes later on) if merging
+ * is possible, otherwise zero.
  *
  * Note that this function searches only for explicit Const nodes and does not
  * try to simplify expressions.
  */
-static bool
+static int
 IsMergeableConstList(List *elements, Const **firstConst, Const **lastConst)
 {
 	ListCell   *temp;
 	Node	   *firstExpr = NULL;
 
 	if (elements == NIL)
-		return false;
+		return 0;
 
 	if (!query_id_const_merge)
 	{
 		/* Merging is disabled, process everything one by one */
-		return false;
+		return 0;
 	}
 
 	firstExpr = linitial(elements);
@@ -273,26 +283,26 @@ IsMergeableConstList(List *elements, Const **firstConst, Const **lastConst)
 	{
 		foreach(temp, elements)
 			if (!IsA(lfirst(temp), Const))
-				return false;
+				return 0;
 
 		*firstConst = (Const *) firstExpr;
 		*lastConst = llast_node(Const, elements);
-		return true;
+		return decimalLength32(elements->length);
 	}
 
 	/*
 	 * If we end up here, it means no constants merging is possible, process
 	 * the list as usual.
 	 */
-	return false;
+	return 0;
 }
 
 #define JUMBLE_NODE(item) \
 	_jumbleNode(jstate, (Node *) expr->item)
 #define JUMBLE_ELEMENTS(list) \
 	_jumbleElements(jstate, (List *) expr->list)
-#define JUMBLE_LOCATION(location, merged) \
-	RecordConstLocation(jstate, expr->location, merged)
+#define JUMBLE_LOCATION(location, magnitude) \
+	RecordConstLocation(jstate, expr->location, magnitude)
 #define JUMBLE_FIELD(item) \
 	AppendJumble(jstate, (const unsigned char *) &(expr->item), sizeof(expr->item))
 #define JUMBLE_FIELD_SINGLE(item) \
@@ -309,15 +319,24 @@ static void
 _jumbleElements(JumbleState *jstate, List *elements)
 {
 	Const *first, *last;
-	if (IsMergeableConstList(elements, &first, &last))
+	int magnitude = IsMergeableConstList(elements, &first, &last);
+
+	if (magnitude)
 	{
 		/*
 		 * Both first and last constants have to be recorded. The first one
 		 * will indicate the merged interval, the last one will tell us the
 		 * length of the interval within the query text.
 		 */
-		RecordConstLocation(jstate, first->location, true);
-		RecordConstLocation(jstate, last->location, true);
+		RecordConstLocation(jstate, first->location, magnitude);
+		RecordConstLocation(jstate, last->location, magnitude);
+
+		/*
+		 * After merging constants down we end up with only two constants, the
+		 * first and the last one. To distinguish the order of magnitute behind
+		 * merged constants, add its value into the jumble.
+		 */
+		JUMBLE_FIELD_SINGLE(magnitude);
 	}
 	else
 	{
diff --git a/src/include/nodes/queryjumble.h b/src/include/nodes/queryjumble.h
index 8daf0725d7..0e69e420b7 100644
--- a/src/include/nodes/queryjumble.h
+++ b/src/include/nodes/queryjumble.h
@@ -26,9 +26,12 @@ typedef struct LocationLen
 
 	/*
 	 * Indicates the constant represents the beginning or the end of a merged
-	 * constants interval.
+	 * constants interval. The value shows how many constants were merged away
+	 * (up to a power of 10), or in other words the order of manitude for
+	 * number of merged constants (i.e. how many digits it has). Otherwise the
+	 * value is 0, indicating that no merging was performed.
 	 */
-	bool		merged;
+	int			magnitude;
 } LocationLen;
 
 /*
@@ -52,6 +55,9 @@ typedef struct JumbleState
 	/* Current number of valid entries in clocations array */
 	int			clocations_count;
 
+	/* Current number of entries with merged constants interval */
+	int			clocations_merged_count;
+
 	/* highest Param id we've seen, in order to start normalization correctly */
 	int			highest_extern_param_id;
 } JumbleState;
-- 
2.45.1


--7t7bac4aexischdh
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename="v21-0004-Introduce-query_id_const_merge_threshold.patch"



^ permalink  raw  reply  [nested|flat] 9+ messages in thread

* [PATCH v20 3/4] Merge constants in ArrayExpr into groups
@ 2024-05-12 09:51  Dmitrii Dolgov <[email protected]>
  0 siblings, 0 replies; 9+ messages in thread

From: Dmitrii Dolgov @ 2024-05-12 09:51 UTC (permalink / raw)

Using query_id_const_merge only first/last element in an ArrayExpr will
be used to compute query id. Extend this to take into account number of
elements, and merge constants into groups based on it. Resulting groups
are powers of 10, i.e. 1 to 9, 10 to 99, etc.

Reviewed-by: Sutou Kouhei
Tested-by: Yasuo Honda
---
 .../pg_stat_statements/expected/merging.out   | 84 +++++++++++++++----
 .../pg_stat_statements/pg_stat_statements.c   | 29 +++++--
 contrib/pg_stat_statements/sql/merging.sql    | 13 +++
 doc/src/sgml/pgstatstatements.sgml            | 11 +--
 src/backend/nodes/queryjumblefuncs.c          | 55 ++++++++----
 src/include/nodes/queryjumble.h               | 10 ++-
 6 files changed, 157 insertions(+), 45 deletions(-)

diff --git a/contrib/pg_stat_statements/expected/merging.out b/contrib/pg_stat_statements/expected/merging.out
index 1e58283afe8..0cb4f67b8b7 100644
--- a/contrib/pg_stat_statements/expected/merging.out
+++ b/contrib/pg_stat_statements/expected/merging.out
@@ -54,11 +54,11 @@ SELECT * FROM test_merge WHERE id IN (1, 2, 3);
 (0 rows)
 
 SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
-                       query                        | calls 
-----------------------------------------------------+-------
- SELECT * FROM test_merge WHERE id IN ($1)          |     1
- SELECT * FROM test_merge WHERE id IN (...)         |     1
- SELECT pg_stat_statements_reset() IS NOT NULL AS t |     1
+                          query                           | calls 
+----------------------------------------------------------+-------
+ SELECT * FROM test_merge WHERE id IN ($1)                |     1
+ SELECT * FROM test_merge WHERE id IN (... [1-9 entries]) |     1
+ SELECT pg_stat_statements_reset() IS NOT NULL AS t       |     1
 (3 rows)
 
 SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9);
@@ -80,7 +80,60 @@ SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
                                  query                                  | calls 
 ------------------------------------------------------------------------+-------
  SELECT * FROM test_merge WHERE id IN ($1)                              |     1
- SELECT * FROM test_merge WHERE id IN (...)                             |     4
+ SELECT * FROM test_merge WHERE id IN (... [1-9 entries])               |     2
+ SELECT * FROM test_merge WHERE id IN (... [10-99 entries])             |     2
+ SELECT pg_stat_statements_reset() IS NOT NULL AS t                     |     1
+ SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C" |     1
+(5 rows)
+
+-- Second order of magnitude, brace yourself
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110);
+ id | data 
+----+------
+(0 rows)
+
+SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
+                            query                             | calls 
+--------------------------------------------------------------+-------
+ SELECT * FROM test_merge WHERE id IN (... [100-999 entries]) |     1
+ SELECT pg_stat_statements_reset() IS NOT NULL AS t           |     1
+(2 rows)
+
+-- With gaps on the threshold
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4);
+ id | data 
+----+------
+(0 rows)
+
+SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
+                          query                           | calls 
+----------------------------------------------------------+-------
+ SELECT * FROM test_merge WHERE id IN (... [1-9 entries]) |     1
+ SELECT pg_stat_statements_reset() IS NOT NULL AS t       |     1
+(2 rows)
+
+SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15);
+ id | data 
+----+------
+(0 rows)
+
+SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
+                                 query                                  | calls 
+------------------------------------------------------------------------+-------
+ SELECT * FROM test_merge WHERE id IN (... [1-9 entries])               |     1
+ SELECT * FROM test_merge WHERE id IN (... [10-99 entries])             |     1
  SELECT pg_stat_statements_reset() IS NOT NULL AS t                     |     1
  SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C" |     1
 (4 rows)
@@ -108,11 +161,12 @@ SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11) and dat
 (0 rows)
 
 SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
-                          query                           | calls 
-----------------------------------------------------------+-------
- SELECT * FROM test_merge WHERE id IN (...) and data = $3 |     3
- SELECT pg_stat_statements_reset() IS NOT NULL AS t       |     1
-(2 rows)
+                                  query                                   | calls 
+--------------------------------------------------------------------------+-------
+ SELECT * FROM test_merge WHERE id IN (... [1-9 entries]) and data = $3   |     1
+ SELECT * FROM test_merge WHERE id IN (... [10-99 entries]) and data = $3 |     2
+ SELECT pg_stat_statements_reset() IS NOT NULL AS t                       |     1
+(3 rows)
 
 -- No constants simplification
 SELECT pg_stat_statements_reset() IS NOT NULL AS t;
@@ -147,10 +201,10 @@ SELECT * FROM test_merge_numeric WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
 (0 rows)
 
 SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
-                       query                        | calls 
-----------------------------------------------------+-------
- SELECT * FROM test_merge_numeric WHERE id IN (...) |     1
- SELECT pg_stat_statements_reset() IS NOT NULL AS t |     1
+                               query                                | calls 
+--------------------------------------------------------------------+-------
+ SELECT * FROM test_merge_numeric WHERE id IN (... [10-99 entries]) |     1
+ SELECT pg_stat_statements_reset() IS NOT NULL AS t                 |     1
 (2 rows)
 
 -- Test constants evaluation, verifies a tricky part to make sure there are no
diff --git a/contrib/pg_stat_statements/pg_stat_statements.c b/contrib/pg_stat_statements/pg_stat_statements.c
index 0e8d42e2054..0ade4cf515f 100644
--- a/contrib/pg_stat_statements/pg_stat_statements.c
+++ b/contrib/pg_stat_statements/pg_stat_statements.c
@@ -2828,6 +2828,8 @@ generate_normalized_query(JumbleState *jstate, const char *query,
 	bool		merged_interval = false;	/* Currently processed constants
 											   belong to a merged constants
 											   interval. */
+	int 		magnitude; 		/* Order of magnitute for number of merged
+								   constants */
 
 
 	/*
@@ -2842,8 +2844,13 @@ generate_normalized_query(JumbleState *jstate, const char *query,
 	 * certainly isn't more than 11 bytes, even if n reaches INT_MAX.  We
 	 * could refine that limit based on the max value of n for the current
 	 * query, but it hardly seems worth any extra effort to do so.
+	 *
+	 * On top of that, each pair of $n symbols representing a merged constants
+	 * interval will be decorated with the explanationary text, adding 14
+	 * bytes.
 	 */
-	norm_query_buflen = query_len + jstate->clocations_count * 10;
+	norm_query_buflen = query_len + jstate->clocations_count * 10 +
+		jstate->clocations_merged_count * 14;
 
 	/* Allocate result buffer */
 	norm_query = palloc(norm_query_buflen + 1);
@@ -2868,7 +2875,8 @@ generate_normalized_query(JumbleState *jstate, const char *query,
 		Assert(len_to_wrt >= 0);
 
 		/* Normal path, non merged constant */
-		if (!jstate->clocations[i].merged)
+		magnitude = jstate->clocations[i].magnitude;
+		if (magnitude == 0)
 		{
 			memcpy(norm_query + n_quer_loc, query + quer_loc, len_to_wrt);
 			n_quer_loc += len_to_wrt;
@@ -2885,13 +2893,23 @@ generate_normalized_query(JumbleState *jstate, const char *query,
 			/*
 			 * We are not inside a merged interval yet, which means it is the
 			 * the first merged constant.
-			 *
+			 */
+			static const uint32 powers_of_ten[] = {
+				1, 10, 100,
+				1000, 10000, 100000,
+				1000000, 10000000, 100000000,
+				1000000000
+			};
+			int lower_merged = powers_of_ten[magnitude - 1];
+			int upper_merged = powers_of_ten[magnitude];
+
+			/*
 			 * A merged constants interval must be represented via two
 			 * constants with the merged flag. Currently we are at the first,
 			 * verify there is another one.
 			 */
 			Assert(i + 1 < jstate->clocations_count);
-			Assert(jstate->clocations[i + 1].merged);
+			Assert(jstate->clocations[i + 1].magnitude > 0);
 
 			memcpy(norm_query + n_quer_loc, query + quer_loc, len_to_wrt);
 			n_quer_loc += len_to_wrt;
@@ -2900,7 +2918,8 @@ generate_normalized_query(JumbleState *jstate, const char *query,
 			merged_interval = true;
 
 			/* Mark the interval in the normalized query */
-			n_quer_loc += sprintf(norm_query + n_quer_loc, "...");
+			n_quer_loc += sprintf(norm_query + n_quer_loc, "... [%d-%d entries]",
+								  lower_merged, upper_merged - 1);
 		}
 
 		/* Otherwise the constant is merged away, move forward */
diff --git a/contrib/pg_stat_statements/sql/merging.sql b/contrib/pg_stat_statements/sql/merging.sql
index 71985bb1cd9..657044faded 100644
--- a/contrib/pg_stat_statements/sql/merging.sql
+++ b/contrib/pg_stat_statements/sql/merging.sql
@@ -27,6 +27,19 @@ SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10);
 SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11);
 SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
 
+-- Second order of magnitude, brace yourself
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110);
+SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
+
+-- With gaps on the threshold
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4);
+SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
+
+SELECT * FROM test_merge WHERE id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15);
+SELECT query, calls FROM pg_stat_statements ORDER BY query COLLATE "C";
+
 -- More conditions in the query
 SELECT pg_stat_statements_reset() IS NOT NULL AS t;
 
diff --git a/doc/src/sgml/pgstatstatements.sgml b/doc/src/sgml/pgstatstatements.sgml
index cbe1f3e1715..12ffd021909 100644
--- a/doc/src/sgml/pgstatstatements.sgml
+++ b/doc/src/sgml/pgstatstatements.sgml
@@ -616,7 +616,7 @@
 =# SELECT * FROM test WHERE a IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12);
 =# SELECT query, calls FROM pg_stat_statements;
 -[ RECORD 1 ]------------------------------
-query | SELECT * FROM test WHERE a IN (...)
+query | SELECT * FROM test WHERE a IN (... [10-99 entries])
 calls | 2
 -[ RECORD 2 ]------------------------------
 query | SELECT pg_stat_statements_reset()
@@ -974,10 +974,11 @@ calls | 1
       with an array of different lenght.
 
       If this parameter is on, an array of constants will contribute only the
-      first and the last elements to the query identifier. It means two
-      occurences of the same query, where the only difference is number of
-      constants in the array, are going to get the same query identifier.
-      Such queries are represented in form <literal>'(...)'</literal>.
+      first element, the last element and the number of elements to the query
+      identifier. It means two occurences of the same query, where the only
+      difference is number of constants in the array, are going to get the
+      same query identifier if the arrays are of similar length.
+      Such queries are represented in form <literal>'(... [10-99 entries])'</literal>.
 
       The parameter could be used to reduce amount of repeating data stored
       via <structname>pg_stat_statements</structname>.  The default value is off.
diff --git a/src/backend/nodes/queryjumblefuncs.c b/src/backend/nodes/queryjumblefuncs.c
index 9e17767100d..e9ede0acb70 100644
--- a/src/backend/nodes/queryjumblefuncs.c
+++ b/src/backend/nodes/queryjumblefuncs.c
@@ -37,6 +37,8 @@
 #include "nodes/queryjumble.h"
 #include "parser/scansup.h"
 
+#include "utils/numutils.h"
+
 #define JUMBLE_SIZE				1024	/* query serialization buffer size */
 
 /* GUC parameters */
@@ -57,7 +59,7 @@ bool		query_id_enabled = false;
 static void AppendJumble(JumbleState *jstate,
 						 const unsigned char *item, Size size);
 static void RecordConstLocation(JumbleState *jstate,
-								int location, bool merged);
+								int location, int magnitude);
 static void _jumbleNode(JumbleState *jstate, Node *node);
 static void _jumbleElements(JumbleState *jstate, List *elements);
 static void _jumbleA_Const(JumbleState *jstate, Node *node);
@@ -123,6 +125,7 @@ JumbleQuery(Query *query)
 	jstate->clocations = (LocationLen *)
 		palloc(jstate->clocations_buf_size * sizeof(LocationLen));
 	jstate->clocations_count = 0;
+	jstate->clocations_merged_count = 0;
 	jstate->highest_extern_param_id = 0;
 
 	/* Compute query ID and mark the Query node with it */
@@ -212,12 +215,15 @@ AppendJumble(JumbleState *jstate, const unsigned char *item, Size size)
  * Record location of constant within query string of query tree that is
  * currently being walked.
  *
- * Merged argument signals that the constant represents the first or the last
- * element in a series of merged constants, and everything but the first/last
- * element contributes nothing to the jumble hash.
+ * Magnitude argument larger than zero signals that the constant represents the
+ * first or the last element in a series of merged constants, and everything
+ * but such first/last element will contribute nothing to the jumble hash. The
+ * magnitute value specifies order of magnitute (i.e. how many digits it has)
+ * for the number of elements in the series, to represent the fact of merging
+ * later on.
  */
 static void
-RecordConstLocation(JumbleState *jstate, int location, bool merged)
+RecordConstLocation(JumbleState *jstate, int location, int magnitude)
 {
 	/* -1 indicates unknown or undefined location */
 	if (location >= 0)
@@ -232,10 +238,12 @@ RecordConstLocation(JumbleState *jstate, int location, bool merged)
 						 sizeof(LocationLen));
 		}
 		jstate->clocations[jstate->clocations_count].location = location;
+		jstate->clocations[jstate->clocations_count].magnitude = magnitude;
 		/* initialize lengths to -1 to simplify third-party module usage */
-		jstate->clocations[jstate->clocations_count].merged = merged;
 		jstate->clocations[jstate->clocations_count].length = -1;
 		jstate->clocations_count++;
+		if (magnitude > 0)
+			jstate->clocations_merged_count++;
 	}
 }
 
@@ -243,24 +251,26 @@ RecordConstLocation(JumbleState *jstate, int location, bool merged)
  * Verify if the provided list contains could be merged down, which means it
  * contains only constant expressions.
  *
- * Return value indicates if merging is possible.
+ * Return value is the order of magnitude (i.e. how many digits it has) for
+ * length of the list (to use for representation purposes later on) if merging
+ * is possible, otherwise zero.
  *
  * Note that this function searches only for explicit Const nodes and does not
  * try to simplify expressions.
  */
-static bool
+static int
 IsMergeableConstList(List *elements, Const **firstConst, Const **lastConst)
 {
 	ListCell   *temp;
 	Node	   *firstExpr = NULL;
 
 	if (elements == NIL)
-		return false;
+		return 0;
 
 	if (!query_id_const_merge)
 	{
 		/* Merging is disabled, process everything one by one */
-		return false;
+		return 0;
 	}
 
 	firstExpr = linitial(elements);
@@ -274,26 +284,26 @@ IsMergeableConstList(List *elements, Const **firstConst, Const **lastConst)
 	{
 		foreach(temp, elements)
 			if (!IsA(lfirst(temp), Const))
-				return false;
+				return 0;
 
 		*firstConst = (Const *) firstExpr;
 		*lastConst = llast_node(Const, elements);
-		return true;
+		return decimalLength32(elements->length);
 	}
 
 	/*
 	 * If we end up here, it means no constants merging is possible, process
 	 * the list as usual.
 	 */
-	return false;
+	return 0;
 }
 
 #define JUMBLE_NODE(item) \
 	_jumbleNode(jstate, (Node *) expr->item)
 #define JUMBLE_ELEMENTS(list) \
 	_jumbleElements(jstate, (List *) expr->list)
-#define JUMBLE_LOCATION(location, merged) \
-	RecordConstLocation(jstate, expr->location, merged)
+#define JUMBLE_LOCATION(location, magnitude) \
+	RecordConstLocation(jstate, expr->location, magnitude)
 #define JUMBLE_FIELD(item) \
 	AppendJumble(jstate, (const unsigned char *) &(expr->item), sizeof(expr->item))
 #define JUMBLE_FIELD_SINGLE(item) \
@@ -310,15 +320,24 @@ static void
 _jumbleElements(JumbleState *jstate, List *elements)
 {
 	Const *first, *last;
-	if (IsMergeableConstList(elements, &first, &last))
+	int magnitude = IsMergeableConstList(elements, &first, &last);
+
+	if (magnitude)
 	{
 		/*
 		 * Both first and last constants have to be recorded. The first one
 		 * will indicate the merged interval, the last one will tell us the
 		 * length of the interval within the query text.
 		 */
-		RecordConstLocation(jstate, first->location, true);
-		RecordConstLocation(jstate, last->location, true);
+		RecordConstLocation(jstate, first->location, magnitude);
+		RecordConstLocation(jstate, last->location, magnitude);
+
+		/*
+		 * After merging constants down we end up with only two constants, the
+		 * first and the last one. To distinguish the order of magnitute behind
+		 * merged constants, add its value into the jumble.
+		 */
+		JUMBLE_FIELD_SINGLE(magnitude);
 	}
 	else
 	{
diff --git a/src/include/nodes/queryjumble.h b/src/include/nodes/queryjumble.h
index 8daf0725d7f..0e69e420b7f 100644
--- a/src/include/nodes/queryjumble.h
+++ b/src/include/nodes/queryjumble.h
@@ -26,9 +26,12 @@ typedef struct LocationLen
 
 	/*
 	 * Indicates the constant represents the beginning or the end of a merged
-	 * constants interval.
+	 * constants interval. The value shows how many constants were merged away
+	 * (up to a power of 10), or in other words the order of manitude for
+	 * number of merged constants (i.e. how many digits it has). Otherwise the
+	 * value is 0, indicating that no merging was performed.
 	 */
-	bool		merged;
+	int			magnitude;
 } LocationLen;
 
 /*
@@ -52,6 +55,9 @@ typedef struct JumbleState
 	/* Current number of valid entries in clocations array */
 	int			clocations_count;
 
+	/* Current number of entries with merged constants interval */
+	int			clocations_merged_count;
+
 	/* highest Param id we've seen, in order to start normalization correctly */
 	int			highest_extern_param_id;
 } JumbleState;
-- 
2.41.0


--eqaczcvvorx3zguj
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
	filename="v20-0004-Introduce-query_id_const_merge_threshold.patch"



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-- links below jump to the message on this page --
2021-01-05 04:34 [PATCH v3 1/3] Move TAP log-searching feature to common modules Kyotaro Horiguchi <[email protected]>
2023-10-15 08:06 [PATCH v16 3/4] Merge constants in ArrayExpr into groups Dmitrii Dolgov <[email protected]>
2023-10-15 08:06 [PATCH v17 3/4] Merge constants in ArrayExpr into groups Dmitrii Dolgov <[email protected]>
2023-10-15 08:06 [PATCH v15 3/4] Merge constants in ArrayExpr into groups Dmitrii Dolgov <[email protected]>
2024-01-22 20:20 [PATCH v19 3/4] Merge constants in ArrayExpr into groups Dmitrii Dolgov <[email protected]>
2024-01-22 20:20 [PATCH v18 3/4] Merge constants in ArrayExpr into groups Dmitrii Dolgov <[email protected]>
2024-05-12 09:51 [PATCH v22 3/4] Merge constants in ArrayExpr into groups Dmitrii Dolgov <[email protected]>
2024-05-12 09:51 [PATCH v20 3/4] Merge constants in ArrayExpr into groups Dmitrii Dolgov <[email protected]>
2024-05-12 09:51 [PATCH v21 3/4] Merge constants in ArrayExpr into groups Dmitrii Dolgov <[email protected]>

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