[pypy-commit] pypy default: Update: mention the varying slow-down factor
arigo
noreply at buildbot.pypy.org
Sat May 10 16:03:49 CEST 2014
Author: Armin Rigo <arigo at tunes.org>
Branch:
Changeset: r71438:05559fd0dfb2
Date: 2014-05-10 16:03 +0200
http://bitbucket.org/pypy/pypy/changeset/05559fd0dfb2/
Log: Update: mention the varying slow-down factor
diff --git a/pypy/doc/stm.rst b/pypy/doc/stm.rst
--- a/pypy/doc/stm.rst
+++ b/pypy/doc/stm.rst
@@ -30,7 +30,8 @@
``pypy-stm`` is a variant of the regular PyPy interpreter. With caveats_
listed below, it should be in theory within 20%-50% slower than a
-regular PyPy, comparing the JIT version in both cases. It is called
+regular PyPy, comparing the JIT version in both cases (but see below!).
+It is called
STM for Software Transactional Memory, which is the internal technique
used (see `Reference to implementation details`_).
@@ -90,6 +91,11 @@
* So far, small examples work fine, but there are still a few bugs.
We're busy fixing them as we find them; feel free to `report bugs`_.
+* It runs with an overhead as low as 20% on examples like "richards".
+ There are also other examples with higher overheads --up to 10x for
+ "translate.py"-- which we are still trying to understand. One suspect
+ is our partial GC implementation, see below.
+
* Currently limited to 1.5 GB of RAM (this is just a parameter in
`core.h`__). Memory overflows are not correctly handled; they cause
segfaults.
More information about the pypy-commit
mailing list