diff --git a/src/backend/utils/cache/relcache.c b/src/backend/utils/cache/relcache.c
index 7aa5d7c7fa..248860758c 100644
--- a/src/backend/utils/cache/relcache.c
+++ b/src/backend/utils/cache/relcache.c
@@ -2357,6 +2357,10 @@ RelationDestroyRelation(Relation relation, bool remember_tupdesc)
 		pfree(relation->rd_options);
 	if (relation->rd_indextuple)
 		pfree(relation->rd_indextuple);
+	if (relation->rd_amcache)
+		pfree(relation->rd_amcache);
+	if (relation->rd_fdwroutine)
+		pfree(relation->rd_fdwroutine);
 	if (relation->rd_indexcxt)
 		MemoryContextDelete(relation->rd_indexcxt);
 	if (relation->rd_rulescxt)
@@ -2369,8 +2373,6 @@ RelationDestroyRelation(Relation relation, bool remember_tupdesc)
 		MemoryContextDelete(relation->rd_pdcxt);
 	if (relation->rd_partcheckcxt)
 		MemoryContextDelete(relation->rd_partcheckcxt);
-	if (relation->rd_fdwroutine)
-		pfree(relation->rd_fdwroutine);
 	pfree(relation);
 }
 
@@ -2415,6 +2417,11 @@ RelationClearRelation(Relation relation, bool rebuild)
 	 */
 	RelationCloseSmgr(relation);
 
+	/* Free AM cached data, if any */
+	if (relation->rd_amcache)
+		pfree(relation->rd_amcache);
+	relation->rd_amcache = NULL;
+
 	/*
 	 * Treat nailed-in system relations separately, they always need to be
 	 * accessible, so we can't blow them away.
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index d35b4a5061..b0fe19ebc5 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -152,13 +152,6 @@ typedef struct RelationData
 	 * those with lefttype and righttype equal to the opclass's opcintype. The
 	 * arrays are indexed by support function number, which is a sufficient
 	 * identifier given that restriction.
-	 *
-	 * Note: rd_amcache is available for index AMs to cache private data about
-	 * an index.  This must be just a cache since it may get reset at any time
-	 * (in particular, it will get reset by a relcache inval message for the
-	 * index).  If used, it must point to a single memory chunk palloc'd in
-	 * rd_indexcxt.  A relcache reset will include freeing that chunk and
-	 * setting rd_amcache = NULL.
 	 */
 	MemoryContext rd_indexcxt;	/* private memory cxt for this stuff */
 	/* use "struct" here to avoid needing to include amapi.h: */
@@ -173,9 +166,19 @@ typedef struct RelationData
 	Oid		   *rd_exclops;		/* OIDs of exclusion operators, if any */
 	Oid		   *rd_exclprocs;	/* OIDs of exclusion ops' procs, if any */
 	uint16	   *rd_exclstrats;	/* exclusion ops' strategy numbers, if any */
-	void	   *rd_amcache;		/* available for use by index AM */
 	Oid		   *rd_indcollation;	/* OIDs of index collations */
 
+	/*
+	 * rd_amcache is available for index and table AMs to cache private data
+	 * about the relation.  This must be just a cache since it may get reset
+	 * at any time (in particular, it will get reset by a relcache inval
+	 * message for the relation).  If used, it must point to a single memory
+	 * chunk palloc'd in CacheMemoryContext, or in rd_indexcxt for an index
+	 * relation.  A relcache reset will include freeing that chunk and setting
+	 * rd_amcache = NULL.
+	 */
+	void	   *rd_amcache;		/* available for use by index/table AM */
+
 	/*
 	 * foreign-table support
 	 *