public inbox for [email protected]  
help / color / mirror / Atom feed
[PATCH 8/8] Ignore correlation for new BRIN opclasses
2+ messages / 2 participants
[nested] [flat]

* [PATCH 8/8] Ignore correlation for new BRIN opclasses
@ 2020-09-12 13:07  Tomas Vondra <[email protected]>
  0 siblings, 0 replies; 2+ messages in thread

From: Tomas Vondra @ 2020-09-12 13:07 UTC (permalink / raw)

The new BRIN opclasses (bloom and minmax-multi) are less sensitive to
poorly correlated data, so just assume the data is perfectly correlated
during costing.

Author: Tomas Vondra <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/access/brin/brin_bloom.c        |  1 +
 src/backend/access/brin/brin_minmax_multi.c |  1 +
 src/backend/utils/adt/selfuncs.c            | 19 ++++++++++++++++++-
 src/include/access/brin_internal.h          |  3 +++
 4 files changed, 23 insertions(+), 1 deletion(-)

diff --git a/src/backend/access/brin/brin_bloom.c b/src/backend/access/brin/brin_bloom.c
index 4494484b3b..46ffc068be 100644
--- a/src/backend/access/brin/brin_bloom.c
+++ b/src/backend/access/brin/brin_bloom.c
@@ -412,6 +412,7 @@ brin_bloom_opcinfo(PG_FUNCTION_ARGS)
 
 	result = palloc0(MAXALIGN(SizeofBrinOpcInfo(1)) +
 					 sizeof(BloomOpaque));
+	result->oi_ignore_correlation = true;
 	result->oi_nstored = 1;
 	result->oi_regular_nulls = true;
 	result->oi_opaque = (BloomOpaque *)
diff --git a/src/backend/access/brin/brin_minmax_multi.c b/src/backend/access/brin/brin_minmax_multi.c
index c90c721cac..a6f79311e2 100644
--- a/src/backend/access/brin/brin_minmax_multi.c
+++ b/src/backend/access/brin/brin_minmax_multi.c
@@ -1737,6 +1737,7 @@ brin_minmax_multi_opcinfo(PG_FUNCTION_ARGS)
 
 	result = palloc0(MAXALIGN(SizeofBrinOpcInfo(1)) +
 					 sizeof(MinmaxMultiOpaque));
+	result->oi_ignore_correlation = true;
 	result->oi_nstored = 1;
 	result->oi_regular_nulls = true;
 	result->oi_opaque = (MinmaxMultiOpaque *)
diff --git a/src/backend/utils/adt/selfuncs.c b/src/backend/utils/adt/selfuncs.c
index 52314d3aa1..0320d128f6 100644
--- a/src/backend/utils/adt/selfuncs.c
+++ b/src/backend/utils/adt/selfuncs.c
@@ -98,6 +98,7 @@
 #include <math.h>
 
 #include "access/brin.h"
+#include "access/brin_internal.h"
 #include "access/brin_page.h"
 #include "access/gin.h"
 #include "access/table.h"
@@ -7352,7 +7353,8 @@ brincostestimate(PlannerInfo *root, IndexPath *path, double loop_count,
 	double		minimalRanges;
 	double		estimatedRanges;
 	double		selec;
-	Relation	indexRel;
+	Relation	indexRel = NULL;
+	TupleDesc	tupdesc = NULL;
 	ListCell   *l;
 	VariableStatData vardata;
 
@@ -7374,6 +7376,7 @@ brincostestimate(PlannerInfo *root, IndexPath *path, double loop_count,
 		 */
 		indexRel = index_open(index->indexoid, NoLock);
 		brinGetStats(indexRel, &statsData);
+		tupdesc = RelationGetDescr(indexRel);
 		index_close(indexRel, NoLock);
 
 		/* work out the actual number of ranges in the index */
@@ -7407,6 +7410,17 @@ brincostestimate(PlannerInfo *root, IndexPath *path, double loop_count,
 	{
 		IndexClause *iclause = lfirst_node(IndexClause, l);
 		AttrNumber	attnum = index->indexkeys[iclause->indexcol];
+		FmgrInfo   *opcInfoFn;
+		BrinOpcInfo *opcInfo;
+		Form_pg_attribute attr = TupleDescAttr(tupdesc, iclause->indexcol);
+		bool		ignore_correlation;
+
+		opcInfoFn = index_getprocinfo(indexRel, iclause->indexcol + 1, BRIN_PROCNUM_OPCINFO);
+
+		opcInfo = (BrinOpcInfo *)
+			DatumGetPointer(FunctionCall1(opcInfoFn, attr->atttypid));
+
+		ignore_correlation = opcInfo->oi_ignore_correlation;
 
 		/* attempt to lookup stats in relation for this index column */
 		if (attnum != 0)
@@ -7477,6 +7491,9 @@ brincostestimate(PlannerInfo *root, IndexPath *path, double loop_count,
 				if (sslot.nnumbers > 0)
 					varCorrelation = Abs(sslot.numbers[0]);
 
+				if (ignore_correlation)
+					varCorrelation = 1.0;
+
 				if (varCorrelation > *indexCorrelation)
 					*indexCorrelation = varCorrelation;
 
diff --git a/src/include/access/brin_internal.h b/src/include/access/brin_internal.h
index fdaff42722..5fbf8cf9c7 100644
--- a/src/include/access/brin_internal.h
+++ b/src/include/access/brin_internal.h
@@ -30,6 +30,9 @@ typedef struct BrinOpcInfo
 	/* Regular processing of NULLs in BrinValues? */
 	bool		oi_regular_nulls;
 
+	/* Ignore correlation during cost estimation */
+	bool		oi_ignore_correlation;
+
 	/* Opaque pointer for the opclass' private use */
 	void	   *oi_opaque;
 
-- 
2.26.2


--------------AC3FFB734F56C5F52D422EFC--





^ permalink  raw  reply  [nested|flat] 2+ messages in thread

* Re: [PATCH] Add <<none>> support to sepgsql_restorecon
@ 2023-01-17 14:59  Ted X Toth <[email protected]>
  0 siblings, 0 replies; 2+ messages in thread

From: Ted X Toth @ 2023-01-17 14:59 UTC (permalink / raw)
  To: [email protected]

The intent of this patch is not to stop all relabeling only to stop sepgsql_restorecon from doing a bulk relabel. I believe sepgsql_object_relabel is called by the 'SECURITY LABEL'  statement which I'm using to set the label of db objects to a specific context which I would not want altered later by a restorecon. This is particularly important in a MLS (multi-level security) environment where for example if a row were labeled at the 'secret' level I would not restorecon to relabel it possibly causing a downgrade.

The new status of this patch is: Ready for Committer


^ permalink  raw  reply  [nested|flat] 2+ messages in thread


end of thread, other threads:[~2023-01-17 14:59 UTC | newest]

Thread overview: 2+ messages (download: mbox mbox.gz follow: Atom feed)
-- links below jump to the message on this page --
2020-09-12 13:07 [PATCH 8/8] Ignore correlation for new BRIN opclasses Tomas Vondra <[email protected]>
2023-01-17 14:59 Re: [PATCH] Add <<none>> support to sepgsql_restorecon Ted X Toth <[email protected]>

This inbox is served by agora; see mirroring instructions
for how to clone and mirror all data and code used for this inbox