diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index afbe068cd0a..63d214782da 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -5570,22 +5570,6 @@ XLOGShmemInit(void *arg)
 	char	   *allocptr;
 	int			i;
 
-#ifdef WAL_DEBUG
-
-	/*
-	 * Create a memory context for WAL debugging that's exempt from the normal
-	 * "no pallocs in critical section" rule. Yes, that can lead to a PANIC if
-	 * an allocation fails, but wal_debug is not for production use anyway.
-	 */
-	if (walDebugCxt == NULL)
-	{
-		walDebugCxt = AllocSetContextCreate(TopMemoryContext,
-											"WAL Debug",
-											ALLOCSET_DEFAULT_SIZES);
-		MemoryContextAllowInCriticalSection(walDebugCxt, true);
-	}
-#endif
-
 	memset(XLogCtl, 0, sizeof(XLogCtlData));
 
 	/*
@@ -5669,6 +5653,30 @@ XLOGShmemAttach(void *arg)
 	WALInsertLocks = XLogCtl->Insert.WALInsertLocks;
 }
 
+/*
+ * Initialize process-local state needed by wal_debug.
+ *
+ * This must be called before XLogInsertRecord().
+ */
+#ifdef WAL_DEBUG
+void
+InitWalDebug(void)
+{
+	/*
+	 * Create a memory context for WAL debugging that's exempt from the normal
+	 * "no pallocs in critical section" rule. Yes, that can lead to a PANIC if
+	 * an allocation fails, but wal_debug is not for production use anyway.
+	 */
+	if (walDebugCxt == NULL)
+	{
+		walDebugCxt = AllocSetContextCreate(TopMemoryContext,
+											"WAL Debug",
+											ALLOCSET_DEFAULT_SIZES);
+		MemoryContextAllowInCriticalSection(walDebugCxt, true);
+	}
+}
+#endif
+
 /*
  * This func must be called ONCE on system install.  It creates pg_control
  * and the initial XLOG segment.
diff --git a/src/backend/access/transam/xloginsert.c b/src/backend/access/transam/xloginsert.c
index c9aff944a2e..2195df85b10 100644
--- a/src/backend/access/transam/xloginsert.c
+++ b/src/backend/access/transam/xloginsert.c
@@ -1437,4 +1437,9 @@ InitXLogInsert(void)
 	if (hdr_scratch == NULL)
 		hdr_scratch = MemoryContextAllocZero(xloginsert_cxt,
 											 HEADER_SCRATCH_SIZE);
+
+	/* Extra initialization for wal_debug */
+#ifdef WAL_DEBUG
+	InitWalDebug();
+#endif
 }
diff --git a/src/include/access/xlog.h b/src/include/access/xlog.h
index 7a590b7e1ea..2bf5714b51e 100644
--- a/src/include/access/xlog.h
+++ b/src/include/access/xlog.h
@@ -234,6 +234,9 @@ extern bool XLogBackgroundFlush(void);
 extern bool XLogNeedsFlush(XLogRecPtr record);
 extern int	XLogFileInit(XLogSegNo logsegno, TimeLineID logtli);
 extern int	XLogFileOpen(XLogSegNo segno, TimeLineID tli);
+#ifdef WAL_DEBUG
+extern void InitWalDebug(void);
+#endif
 
 extern void CheckXLogRemoved(XLogSegNo segno, TimeLineID tli);
 extern XLogSegNo XLogGetLastRemovedSegno(void);