[pypy-commit] extradoc extradoc: rewrite

alex_gaynor noreply at buildbot.pypy.org
Sat Oct 26 01:25:41 CEST 2013


Author: Alex Gaynor <alex.gaynor at gmail.com>
Branch: extradoc
Changeset: r5103:b710505c06d1
Date: 2013-10-25 16:25 -0700
http://bitbucket.org/pypy/extradoc/changeset/b710505c06d1/

Log:	rewrite

diff --git a/blog/draft/coverage.rst b/blog/draft/coverage.rst
--- a/blog/draft/coverage.rst
+++ b/blog/draft/coverage.rst
@@ -55,13 +55,13 @@
 it did it in a particularly insidious way — the JIT had no idea it was being
 disabled!
 
-Instead, every time PyPy discovered one of your functions was a hotspot, it
-would start tracing, to observe what the program was doing, and right when it
-was about to finish, ``coverage`` would run, and it would cause the JIT to
-abort. Tracing is a slow process, it makes up for it by generating fast machine
-code at the end, but tracing is still incredibly slow. But we never actually
-got to the "generate fast machine code" stage. Instead we'd pay all the cost of
-tracing, but then we'd abort, and reap none of the benefits.
+Instead, every time PyPy discovered that one of your functions was a hotspot,
+it would start tracing to observe what the program was doing, and right when it
+was about to finish, ``coverage`` would run and cause the JIT to abort. Tracing
+is a slow process, it makes up for it by generating fast machine code at the
+end, but tracing is still incredibly slow. But we never actually got to the
+"generate fast machine code" stage. Instead we'd pay all the cost of tracing,
+but then we'd abort, and reap none of the benefits.
 
 To fix this, we adjusted some of the heuristics in the JIT, to better show it
 how ``sys.settrace()`` works. Previously the JIT saw "here's an opaque function


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