diff --git a/Doc/whatsnew/3.5.rst b/Doc/whatsnew/3.5.rst
--- a/Doc/whatsnew/3.5.rst
+++ b/Doc/whatsnew/3.5.rst
@@ -379,7 +379,8 @@ The following performance enhancements h
   (:issue:`21486`, :issue:`21487`, :issue:`20826`)
 
 * Many operations on :class:`io.BytesIO` are now 50% to 100% faster.
-  (Contributed by Serhiy Storchaka in :issue:`15381`.)
+  (Contributed by Serhiy Storchaka in :issue:`15381` and David Wilson in
+  :issue:`22003`.)
 
 
 Build and C API Changes