v1-0001-Use-pgBufferUsage-for-block-reporting-in-analyze.patch

From 889828d00ce586f26335f9fcc77d68c28374da6c Mon Sep 17 00:00:00 2001
From: Anthonin Bonnefoy <anthonin.bonnefoy@datadoghq.com>
Date: Wed, 24 Apr 2024 10:40:33 +0200
Subject: Use pgBufferUsage for block reporting in analyze

pgBufferUsage is already providing block usage tracking. Replace
VacuumPage{Hit,Miss,Dirty} Vacuum specific variables by pgBufferUsage
in analyze command.

Those variables were only used in two places, verbose reporting
in vacuum and analyze. 5cd72cc0c5017a9d4de8b5d465a75946da5abd1d already
removed their usage in the vacuum command.

This makes VacuumPage{Hit,Miss,Dirty} completely unused and removable.
This commit removes both their calls in bufmgr and their declarations.
---
 src/backend/commands/analyze.c        | 24 +++++++++++-------------
 src/backend/commands/vacuum.c         |  3 ---
 src/backend/commands/vacuumparallel.c |  3 ---
 src/backend/storage/buffer/bufmgr.c   |  4 ----
 src/backend/utils/init/globals.c      |  4 ----
 src/include/miscadmin.h               |  4 ----
 6 files changed, 11 insertions(+), 31 deletions(-)

diff --git a/src/backend/commands/analyze.c b/src/backend/commands/analyze.c
index 7d2cd24997..cab5792525 100644
--- a/src/backend/commands/analyze.c
+++ b/src/backend/commands/analyze.c
@@ -303,9 +303,8 @@ do_analyze_rel(Relation onerel, VacuumParams *params,
 	Oid			save_userid;
 	int			save_sec_context;
 	int			save_nestlevel;
-	int64		AnalyzePageHit = VacuumPageHit;
-	int64		AnalyzePageMiss = VacuumPageMiss;
-	int64		AnalyzePageDirty = VacuumPageDirty;
+	BufferUsage startbufferusage = pgBufferUsage;
+	BufferUsage bufferusage;
 	PgStat_Counter startreadtime = 0;
 	PgStat_Counter startwritetime = 0;
 
@@ -737,9 +736,8 @@ do_analyze_rel(Relation onerel, VacuumParams *params,
 			 * happened as part of the analyze by subtracting out the
 			 * pre-analyze values which we saved above.
 			 */
-			AnalyzePageHit = VacuumPageHit - AnalyzePageHit;
-			AnalyzePageMiss = VacuumPageMiss - AnalyzePageMiss;
-			AnalyzePageDirty = VacuumPageDirty - AnalyzePageDirty;
+			memset(&bufferusage, 0, sizeof(BufferUsage));
+			BufferUsageAccumDiff(&bufferusage, &pgBufferUsage, &startbufferusage);
 
 			/*
 			 * We do not expect an analyze to take > 25 days and it simplifies
@@ -765,10 +763,10 @@ do_analyze_rel(Relation onerel, VacuumParams *params,
 
 			if (delay_in_ms > 0)
 			{
-				read_rate = (double) BLCKSZ * AnalyzePageMiss / (1024 * 1024) /
-					(delay_in_ms / 1000.0);
-				write_rate = (double) BLCKSZ * AnalyzePageDirty / (1024 * 1024) /
-					(delay_in_ms / 1000.0);
+				read_rate = (double) BLCKSZ * (bufferusage.shared_blks_read + bufferusage.local_blks_read) /
+					(1024 * 1024) / (delay_in_ms / 1000.0);
+				write_rate = (double) BLCKSZ * (bufferusage.shared_blks_dirtied + bufferusage.local_blks_dirtied) /
+					(1024 * 1024) / (delay_in_ms / 1000.0);
 			}
 
 			/*
@@ -792,9 +790,9 @@ do_analyze_rel(Relation onerel, VacuumParams *params,
 			appendStringInfo(&buf, _("avg read rate: %.3f MB/s, avg write rate: %.3f MB/s\n"),
 							 read_rate, write_rate);
 			appendStringInfo(&buf, _("buffer usage: %lld hits, %lld misses, %lld dirtied\n"),
-							 (long long) AnalyzePageHit,
-							 (long long) AnalyzePageMiss,
-							 (long long) AnalyzePageDirty);
+							 (long long) (bufferusage.shared_blks_hit + bufferusage.local_blks_hit),
+							 (long long) (bufferusage.shared_blks_read + bufferusage.local_blks_read),
+							 (long long) (bufferusage.shared_blks_dirtied + bufferusage.local_blks_dirtied));
 			appendStringInfo(&buf, _("system usage: %s"), pg_rusage_show(&ru0));
 
 			ereport(LOG,
diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index 521ee74586..4d8c0e511d 100644
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -603,9 +603,6 @@ vacuum(List *relations, VacuumParams *params, BufferAccessStrategy bstrategy,
 		VacuumFailsafeActive = false;
 		VacuumUpdateCosts();
 		VacuumCostBalance = 0;
-		VacuumPageHit = 0;
-		VacuumPageMiss = 0;
-		VacuumPageDirty = 0;
 		VacuumCostBalanceLocal = 0;
 		VacuumSharedCostBalance = NULL;
 		VacuumActiveNWorkers = NULL;
diff --git a/src/backend/commands/vacuumparallel.c b/src/backend/commands/vacuumparallel.c
index f26070bff2..22c057fe61 100644
--- a/src/backend/commands/vacuumparallel.c
+++ b/src/backend/commands/vacuumparallel.c
@@ -1043,9 +1043,6 @@ parallel_vacuum_main(dsm_segment *seg, shm_toc *toc)
 	/* Set cost-based vacuum delay */
 	VacuumUpdateCosts();
 	VacuumCostBalance = 0;
-	VacuumPageHit = 0;
-	VacuumPageMiss = 0;
-	VacuumPageDirty = 0;
 	VacuumCostBalanceLocal = 0;
 	VacuumSharedCostBalance = &(shared->cost_balance);
 	VacuumActiveNWorkers = &(shared->active_nworkers);
diff --git a/src/backend/storage/buffer/bufmgr.c b/src/backend/storage/buffer/bufmgr.c
index 49637284f9..996ee6fdc8 100644
--- a/src/backend/storage/buffer/bufmgr.c
+++ b/src/backend/storage/buffer/bufmgr.c
@@ -1127,7 +1127,6 @@ PinBufferForBlock(Relation rel,
 	}
 	if (*foundPtr)
 	{
-		VacuumPageHit++;
 		pgstat_count_io_op(io_object, io_context, IOOP_HIT);
 		if (VacuumCostActive)
 			VacuumCostBalance += VacuumCostPageHit;
@@ -1519,7 +1518,6 @@ WaitReadBuffers(ReadBuffersOperation *operation)
 											  false);
 		}
 
-		VacuumPageMiss += io_buffers_len;
 		if (VacuumCostActive)
 			VacuumCostBalance += VacuumCostPageMiss * io_buffers_len;
 	}
@@ -2513,7 +2511,6 @@ MarkBufferDirty(Buffer buffer)
 	 */
 	if (!(old_buf_state & BM_DIRTY))
 	{
-		VacuumPageDirty++;
 		pgBufferUsage.shared_blks_dirtied++;
 		if (VacuumCostActive)
 			VacuumCostBalance += VacuumCostPageDirty;
@@ -5036,7 +5033,6 @@ MarkBufferDirtyHint(Buffer buffer, bool buffer_std)
 
 		if (dirtied)
 		{
-			VacuumPageDirty++;
 			pgBufferUsage.shared_blks_dirtied++;
 			if (VacuumCostActive)
 				VacuumCostBalance += VacuumCostPageDirty;
diff --git a/src/backend/utils/init/globals.c b/src/backend/utils/init/globals.c
index cc61937eef..ba7f45e8a2 100644
--- a/src/backend/utils/init/globals.c
+++ b/src/backend/utils/init/globals.c
@@ -151,10 +151,6 @@ int			VacuumCostPageDirty = 20;
 int			VacuumCostLimit = 200;
 double		VacuumCostDelay = 0;
 
-int64		VacuumPageHit = 0;
-int64		VacuumPageMiss = 0;
-int64		VacuumPageDirty = 0;
-
 int			VacuumCostBalance = 0;	/* working state for vacuum */
 bool		VacuumCostActive = false;
 
diff --git a/src/include/miscadmin.h b/src/include/miscadmin.h
index 90f9b21b25..6d07005d39 100644
--- a/src/include/miscadmin.h
+++ b/src/include/miscadmin.h
@@ -283,10 +283,6 @@ extern PGDLLIMPORT int VacuumCostPageDirty;
 extern PGDLLIMPORT int VacuumCostLimit;
 extern PGDLLIMPORT double VacuumCostDelay;
 
-extern PGDLLIMPORT int64 VacuumPageHit;
-extern PGDLLIMPORT int64 VacuumPageMiss;
-extern PGDLLIMPORT int64 VacuumPageDirty;
-
 extern PGDLLIMPORT int VacuumCostBalance;
 extern PGDLLIMPORT bool VacuumCostActive;
 
-- 
2.39.3 (Apple Git-146)