From d7ecf2a8b1d2d23aa21c1a2c5cc0d24e7aa4b543 Mon Sep 17 00:00:00 2001
From: Anthonin Bonnefoy <anthonin.bonnefoy@datadoghq.com>
Date: Mon, 22 Apr 2024 09:14:50 +0200
Subject: Remove unused tracking of vacuum buffer usage

Vacuum now relies on pgBufferUsage to track block usage making
VacuumPage{Hit,Miss,Dirty} unnecessary. Remove initialization and
increment of the vacuum specific variables used for block usage.
---
 src/backend/commands/vacuum.c         | 3 ---
 src/backend/commands/vacuumparallel.c | 3 ---
 src/backend/storage/buffer/bufmgr.c   | 4 ----
 3 files changed, 10 deletions(-)

diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index b589279d49..192a0c74f9 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;
-- 
2.39.3 (Apple Git-146)