Effectively do not remove any entries

src/backend/distributed/commands/utility_hook.c

@@ -53,7 +53,6 @@
 #include "distributed/multi_explain.h"
 #include "distributed/multi_physical_planner.h"
 #include "distributed/resource_lock.h"
-#include "distributed/shared_connection_stats.h"
 #include "distributed/transmit.h"
 #include "distributed/version_compat.h"
 #include "distributed/worker_transaction.h"
@@ -454,7 +453,6 @@ multi_ProcessUtility(PlannedStmt *pstmt,
 	if (IsDropCitusStmt(parsetree))
 	{
 		StopMaintenanceDaemon(MyDatabaseId);
-		RemoveAllSharedConnectionEntries();
 	}
 
 	pstmt->utilityStmt = parsetree;

src/backend/distributed/connection/shared_connection_stats.c

@@ -177,21 +177,6 @@ StoreAllConnections(Tuplestorestate *tupleStore, TupleDesc tupleDescriptor)
 }
 
 
-/*
- * RemoveAllSharedConnectionEntries removes all the entries in SharedConnStatsHash.
- */
-void
-RemoveAllSharedConnectionEntries(void)
-{
-	/* we're reading all shared connections, prevent any changes */
-	LockConnectionSharedMemory(LW_EXCLUSIVE);
-
-	hash_delete_all(SharedConnStatsHash);
-
-	UnLockConnectionSharedMemory();
-}
-
-
 /*
  * RemoveInactiveNodesFromSharedConnections goes over the SharedConnStatsHash
  * and removes the inactive entries.
@@ -205,12 +190,20 @@ RemoveInactiveNodesFromSharedConnections(void)
 	HASH_SEQ_STATUS status;
 	SharedConnStatsHashEntry *connectionEntry = NULL;
 
+	int entryCount = hash_get_num_entries(SharedConnStatsHash);
+	if (entryCount + 1 < MaxWorkerNodesTracked)
+	{
+		UnLockConnectionSharedMemory();
+
+		return;
+	}
+
 	hash_seq_init(&status, SharedConnStatsHash);
 	while ((connectionEntry = (SharedConnStatsHashEntry *) hash_seq_search(&status)) != 0)
 	{
 		SharedConnStatsHashKey connectionKey = connectionEntry->key;
-		WorkerNode *workerNode = FindWorkerNode(connectionKey.hostname,
-												connectionKey.port);
+		WorkerNode *workerNode =
+			FindWorkerNode(connectionKey.hostname, connectionKey.port);
 
 		if (workerNode == NULL || !workerNode->isActive)
 		{

src/include/distributed/shared_connection_stats.h

@@ -19,7 +19,6 @@ extern void InitializeSharedConnectionStats(void);
 extern void WaitForSharedConnection(void);
 extern void WakeupWaiterBackendsForSharedConnection(void);
 extern void RemoveInactiveNodesFromSharedConnections(void);
-extern void RemoveAllSharedConnectionEntries(void);
 extern int GetMaxSharedPoolSize(void);
 extern bool TryToIncrementSharedConnectionCounter(const char *hostname, int port);
 extern void WaitOrErrorForSharedConnection(const char *hostname, int port);