diff --git a/src/backend/storage/ipc/dsm.c b/src/backend/storage/ipc/dsm.c
index f1f75b73f5..08b6fa8155 100644
--- a/src/backend/storage/ipc/dsm.c
+++ b/src/backend/storage/ipc/dsm.c
@@ -673,6 +673,8 @@ dsm_detach_all(void)
  *
  * This may cause the shared memory segment to be remapped at a different
  * address.  For the caller's convenience, we return the mapped address.
+ *
+ * This interface is deprecated and will be removed in a future release.
  */
 void *
 dsm_resize(dsm_segment *seg, Size size)
@@ -690,6 +692,8 @@ dsm_resize(dsm_segment *seg, Size size)
  * mapping using dsm_resize(), but we've still only got the initial
  * portion mapped.  Since this might change the address at which the
  * segment is mapped, we return the new mapped address.
+ *
+ * This interface is deprecated and will be removed in a future release.
  */
 void *
 dsm_remap(dsm_segment *seg)
diff --git a/src/backend/storage/ipc/dsm_impl.c b/src/backend/storage/ipc/dsm_impl.c
index b79701d837..0b0874779b 100644
--- a/src/backend/storage/ipc/dsm_impl.c
+++ b/src/backend/storage/ipc/dsm_impl.c
@@ -205,6 +205,8 @@ dsm_impl_op(dsm_op op, dsm_handle handle, Size request_size,
  * since AIX allows shmctl(shmid, SHM_RESIZE, &buffer), though you apparently
  * can't resize segments to anything larger than 256MB that way.  For now,
  * we keep it simple.)
+ *
+ * This interface is deprecated and will be removed in a future release.
  */
 bool
 dsm_impl_can_resize(void)
diff --git a/src/include/storage/dsm.h b/src/include/storage/dsm.h
index 169de946f7..f5f77b017a 100644
--- a/src/include/storage/dsm.h
+++ b/src/include/storage/dsm.h
@@ -36,8 +36,8 @@ extern void dsm_set_control_handle(dsm_handle h);
 /* Functions that create, update, or remove mappings. */
 extern dsm_segment *dsm_create(Size size, int flags);
 extern dsm_segment *dsm_attach(dsm_handle h);
-extern void *dsm_resize(dsm_segment *seg, Size size);
-extern void *dsm_remap(dsm_segment *seg);
+extern void *dsm_resize(dsm_segment *seg, Size size);	/* deprecated */
+extern void *dsm_remap(dsm_segment *seg);				/* deprecated */
 extern void dsm_detach(dsm_segment *seg);
 
 /* Resource management functions. */
diff --git a/src/include/storage/dsm_impl.h b/src/include/storage/dsm_impl.h
index 0e5730f7c5..89a0ea82b7 100644
--- a/src/include/storage/dsm_impl.h
+++ b/src/include/storage/dsm_impl.h
@@ -70,7 +70,7 @@ extern bool dsm_impl_op(dsm_op op, dsm_handle handle, Size request_size,
 			int elevel);
 
 /* Some implementations cannot resize segments.  Can this one? */
-extern bool dsm_impl_can_resize(void);
+extern bool dsm_impl_can_resize(void);					/* deprecated */
 
 /* Implementation-dependent actions required to keep segment until shutdown. */
 extern void dsm_impl_pin_segment(dsm_handle handle, void *impl_private,