Note a performance improvement on PyPy in the release notes.

sys.exc_info() is very slow on pypy.  Commit
24c3d41748728cf4f3ea1509044b4abc7cea666e removed an unconditional
call to sys.exc_info when there is no error.  Performance on
demo/benchmark/benchmark.py went from 3k qps to 5k.

diff --git a/website/sphinx/releases/next.rst b/website/sphinx/releases/next.rst
index 68241f9d749aefb22b13226e780b7808413517db..164cad6601942011a4748baa2ee90dc8a9fb44a9 100644 (file)
--- a/website/sphinx/releases/next.rst
+++ b/website/sphinx/releases/next.rst
@@ -159,6 +159,8 @@ General
   which will be used for SSL certificate validation when applicable.
   Additionally, when supported (on Python 3.2+), this hostname
   will be sent via SNI (and this is supported by `tornado.simple_httpclient`)
+* Fixed a major performance regression when run on PyPy (introduced in
+  Tornado 2.3).
 
 `tornado.netutil`
 ~~~~~~~~~~~~~~~~~