diff --git a/src/backend/storage/ipc/dsm_impl.c b/src/backend/storage/ipc/dsm_impl.c
index a5dbd662b2f..5f96bcf5b2f 100644
--- a/src/backend/storage/ipc/dsm_impl.c
+++ b/src/backend/storage/ipc/dsm_impl.c
@@ -868,7 +868,7 @@ dsm_impl_mmap(dsm_op op, dsm_handle handle, Size request_size,
 		 * transferring data to the kernel.
 		 */
 		char	   *zbuffer = (char *) palloc0(ZBUFFER_SIZE);
-		uint32		remaining = request_size;
+		Size		remaining = request_size;
 		bool		success = true;
 
 		/*