From 9c4c40217b4615f003ed3460d3e73b38459791a2 Mon Sep 17 00:00:00 2001
From: Gokhan Gulbiz <ggulbiz@gmail.com>
Date: Tue, 9 May 2023 17:05:31 +0300
Subject: [PATCH] Use HASH_BLOB flag for tenants

---
 .../distributed/utils/citus_stat_tenants.c    | 41 +------------------
 .../distributed/utils/citus_stat_tenants.h    |  2 +
 2 files changed, 4 insertions(+), 39 deletions(-)

diff --git a/src/backend/distributed/utils/citus_stat_tenants.c b/src/backend/distributed/utils/citus_stat_tenants.c
index eff70839b..3f28e215c 100644
--- a/src/backend/distributed/utils/citus_stat_tenants.c
+++ b/src/backend/distributed/utils/citus_stat_tenants.c
@@ -68,8 +68,6 @@ static TenantStats * CreateTenantStats(MultiTenantMonitor *monitor, TimestampTz
 static TenantStatsHashKey * CreateTenantStatsHashKey(char *tenantAttribute, uint32
 													 colocationGroupId);
 static TenantStats * FindTenantStats(MultiTenantMonitor *monitor);
-static uint32 TenantStatsHashFn(const void *key, Size keysize);
-static int TenantStatsMatchFn(const void *key1, const void *key2, Size keysize);
 static size_t MultiTenantMonitorshmemSize(void);
 static char * ExtractTopComment(const char *inputString);
 static char * EscapeCommentChars(const char *str);
@@ -636,13 +634,11 @@ CreateSharedMemoryForMultiTenantMonitor()
 	memset(&info, 0, sizeof(info));
 	info.keysize = sizeof(TenantStatsHashKey);
 	info.entrysize = sizeof(TenantStats);
-	info.hash = TenantStatsHashFn;
-	info.match = TenantStatsMatchFn;
 
 	monitor->tenants = ShmemInitHash("citus_stats_tenants hash",
 									 StatTenantsLimit * 3, StatTenantsLimit * 3,
-									 &info, HASH_ELEM | HASH_FUNCTION | HASH_COMPARE |
-									 HASH_SHARED_MEM);
+									 &info, HASH_ELEM |
+									 HASH_SHARED_MEM | HASH_BLOBS);
 
 	return monitor;
 }
@@ -768,39 +764,6 @@ CreateTenantStatsHashKey(char *tenantAttribute, uint32 colocationGroupId)
 }
 
 
-/*
- * CitusQuerysStatsHashFn calculates and returns hash value for a key
- */
-static uint32
-TenantStatsHashFn(const void *key, Size keysize)
-{
-	const TenantStatsHashKey *k = (const TenantStatsHashKey *) key;
-
-	return hash_any((const unsigned char *) (k->tenantAttribute), strlen(
-						k->tenantAttribute)) ^
-		   hash_uint32((uint32) k->colocationGroupId);
-}
-
-
-/*
- * TenantStatsMatchFn compares two keys - zero means match.
- * See definition of HashCompareFunc in hsearch.h for more info.
- */
-static int
-TenantStatsMatchFn(const void *key1, const void *key2, Size keysize)
-{
-	const TenantStatsHashKey *k1 = (const TenantStatsHashKey *) key1;
-	const TenantStatsHashKey *k2 = (const TenantStatsHashKey *) key2;
-
-	if (strcmp(k1->tenantAttribute, k2->tenantAttribute) == 0 &&
-		k1->colocationGroupId == k2->colocationGroupId)
-	{
-		return 0;
-	}
-	return 1;
-}
-
-
 /*
  * MultiTenantMonitorshmemSize calculates the size of the multi tenant monitor using
  * StatTenantsLimit parameter.
diff --git a/src/include/distributed/utils/citus_stat_tenants.h b/src/include/distributed/utils/citus_stat_tenants.h
index bbea85d3e..6acbd5de7 100644
--- a/src/include/distributed/utils/citus_stat_tenants.h
+++ b/src/include/distributed/utils/citus_stat_tenants.h
@@ -11,6 +11,7 @@
 #ifndef CITUS_ATTRIBUTE_H
 #define CITUS_ATTRIBUTE_H
 
+#include "distributed/hash_helpers.h"
 #include "executor/execdesc.h"
 #include "executor/executor.h"
 #include "storage/lwlock.h"
@@ -28,6 +29,7 @@ typedef struct TenantStatsHashKey
 	char tenantAttribute[MAX_TENANT_ATTRIBUTE_LENGTH];
 	int colocationGroupId;
 } TenantStatsHashKey;
+assert_valid_hash_key2(TenantStatsHashKey, tenantAttribute, colocationGroupId);
 
 /*
  * TenantStats is the struct that keeps statistics about one tenant.