diff --git a/src/include/utils/memutils.h b/src/include/utils/memutils.h
index 149bb9b9b56..64ff2a97c45 100644
--- a/src/include/utils/memutils.h
+++ b/src/include/utils/memutils.h
@@ -141,14 +141,26 @@ extern MemoryContext AllocSetContextCreate(MemoryContext parent,
 #define ALLOCSET_DEFAULT_MINSIZE   0
 #define ALLOCSET_DEFAULT_INITSIZE  (8 * 1024)
 #define ALLOCSET_DEFAULT_MAXSIZE   (8 * 1024 * 1024)
+#define ALLOCSET_DEFAULT_SIZES \
+	ALLOCSET_DEFAULT_MINSIZE, ALLOCSET_DEFAULT_INITSIZE, ALLOCSET_DEFAULT_MAXSIZE
 
 /*
- * Recommended alloc parameters for "small" contexts that are not expected
+ * Recommended alloc parameters for "small" contexts that are never expected
  * to contain much data (for example, a context to contain a query plan).
  */
 #define ALLOCSET_SMALL_MINSIZE	 0
 #define ALLOCSET_SMALL_INITSIZE  (1 * 1024)
 #define ALLOCSET_SMALL_MAXSIZE	 (8 * 1024)
+#define ALLOCSET_SMALL_SIZES \
+	ALLOCSET_SMALL_MINSIZE, ALLOCSET_SMALL_INITSIZE, ALLOCSET_SMALL_MAXSIZE
+
+/*
+ * Recommended alloc parameters for contexts that should start out small,
+ * but might sometimes grow big.
+ */
+#define ALLOCSET_START_SMALL_SIZES \
+	ALLOCSET_SMALL_MINSIZE, ALLOCSET_SMALL_INITSIZE, ALLOCSET_DEFAULT_MAXSIZE
+
 
 /*
  * Threshold above which a request in an AllocSet context is certain to be