5 files changed, 35 insertions, 9 deletions
diff --git a/src/backend/replication/slot.c b/src/backend/replication/slot.c
index e5e0cf87688..5da5fa825a2 100644
--- a/src/backend/replication/slot.c
+++ b/src/backend/replication/slot.c
@@ -46,6 +46,7 @@
 #include "pgstat.h"
 #include "replication/slot.h"
 #include "storage/fd.h"
+#include "storage/ipc.h"
 #include "storage/proc.h"
 #include "storage/procarray.h"
 #include "utils/builtins.h"
@@ -99,6 +100,7 @@ ReplicationSlot *MyReplicationSlot = NULL;
 int			max_replication_slots = 0;	/* the maximum number of replication
 										 * slots */
 
+static void ReplicationSlotShmemExit(int code, Datum arg);
 static void ReplicationSlotDropAcquired(void);
 static void ReplicationSlotDropPtr(ReplicationSlot *slot);
 
@@ -161,6 +163,29 @@ ReplicationSlotsShmemInit(void)
 }
 
 /*
+ * Register the callback for replication slot cleanup and releasing.
+ */
+void
+ReplicationSlotInitialize(void)
+{
+	before_shmem_exit(ReplicationSlotShmemExit, 0);
+}
+
+/*
+ * Release and cleanup replication slots.
+ */
+static void
+ReplicationSlotShmemExit(int code, Datum arg)
+{
+	/* Make sure active replication slots are released */
+	if (MyReplicationSlot != NULL)
+		ReplicationSlotRelease();
+
+	/* Also cleanup all the temporary slots. */
+	ReplicationSlotCleanup();
+}
+
+/*
  * Check whether the passed slot name is valid and report errors at elevel.
  *
  * Slot names may consist out of [a-z0-9_]{1,NAMEDATALEN-1} which should allow
diff --git a/src/backend/storage/lmgr/proc.c b/src/backend/storage/lmgr/proc.c
index 37f032e7b95..90283f8a9f5 100644
--- a/src/backend/storage/lmgr/proc.c
+++ b/src/backend/storage/lmgr/proc.c
@@ -831,13 +831,6 @@ ProcKill(int code, Datum arg)
 	/* Cancel any pending condition variable sleep, too */
 	ConditionVariableCancelSleep();
 
-	/* Make sure active replication slots are released */
-	if (MyReplicationSlot != NULL)
-		ReplicationSlotRelease();
-
-	/* Also cleanup all the temporary slots. */
-	ReplicationSlotCleanup();
-
 	/*
 	 * Detach from any lock group of which we are a member.  If the leader
 	 * exist before all other group members, its PGPROC will remain allocated
diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
index fda2e9360e2..38d8b97894c 100644
--- a/src/backend/tcop/postgres.c
+++ b/src/backend/tcop/postgres.c
@@ -4261,8 +4261,8 @@ PostgresMain(const char *dbname, const char *username)
 		 * We can't release replication slots inside AbortTransaction() as we
 		 * need to be able to start and abort transactions while having a slot
 		 * acquired. But we never need to hold them across top level errors,
-		 * so releasing here is fine. There's another cleanup in ProcKill()
-		 * ensuring we'll correctly cleanup on FATAL errors as well.
+		 * so releasing here is fine. There also is a before_shmem_exit()
+		 * callback ensuring correct cleanup on FATAL errors.
 		 */
 		if (MyReplicationSlot != NULL)
 			ReplicationSlotRelease();
diff --git a/src/backend/utils/init/postinit.c b/src/backend/utils/init/postinit.c
index 02207a5b6f8..e2208151e45 100644
--- a/src/backend/utils/init/postinit.c
+++ b/src/backend/utils/init/postinit.c
@@ -43,6 +43,7 @@
 #include "pgstat.h"
 #include "postmaster/autovacuum.h"
 #include "postmaster/postmaster.h"
+#include "replication/slot.h"
 #include "replication/walsender.h"
 #include "storage/bufmgr.h"
 #include "storage/fd.h"
@@ -626,6 +627,12 @@ BaseInit(void)
 	 * ever try to insert XLOG.
 	 */
 	InitXLogInsert();
+
+	/*
+	 * Initialize replication slots after pgstat. The exit hook might need to
+	 * drop ephemeral slots, which in turn triggers stats reporting.
+	 */
+	ReplicationSlotInitialize();
 }
 
 
diff --git a/src/include/replication/slot.h b/src/include/replication/slot.h
index f833b1d6dc9..24b30210c3e 100644
--- a/src/include/replication/slot.h
+++ b/src/include/replication/slot.h
@@ -206,6 +206,7 @@ extern void ReplicationSlotSave(void);
 extern void ReplicationSlotMarkDirty(void);
 
 /* misc stuff */
+extern void ReplicationSlotInitialize(void);
 extern bool ReplicationSlotValidateName(const char *name, int elevel);
 extern void ReplicationSlotReserveWal(void);
 extern void ReplicationSlotsComputeRequiredXmin(bool already_locked);