This issue tracker has been migrated to GitHub, and is currently read-only.
For more information, see the GitHub FAQs in the Python's Developer Guide.

Author pitrou
Recipients alex, belopolsky, benjamin.peterson, dmalcolm, jhylton, nnorwitz, pitrou, rhettinger, sdahlbac, thomaslee, titanstar
Date 2010-11-12.21:24:29
SpamBayes Score 2.5089e-10
Marked as misclassified No
Message-id <1289597080.96.0.9732660757.issue10401@psf.upfronthosting.co.za>
In-reply-to
Content
Here is the Nth patch for a globals/builtins cache. As other caches at the same kind, it shows very small to no gain on non-micro benchmarks, showing that contrary to popular belief, globals/builtins lookup are not a major roadblock in today's Python performance.

However, this patch could be useful in combination with other optimizations such as issue10399.  Indeed, using the globals/builtins version id, it is easy and very cheap to detect whether the function pointed to by a global name has changed or not.

As for micro-benchmarks, they show that there is indeed a good improvement on builtins lookups:

$ ./python -m timeit "x=len;x=len;x=len;x=len;x=len;x=len;x=len;x=len;x=len;x=len;"
-> without patch:
1000000 loops, best of 3: 0.282 usec per loop
-> with patch:
10000000 loops, best of 3: 0.183 usec per loop
History
Date User Action Args
2010-11-12 21:24:41pitrousetrecipients: + pitrou, jhylton, nnorwitz, rhettinger, belopolsky, sdahlbac, titanstar, thomaslee, benjamin.peterson, alex, dmalcolm
2010-11-12 21:24:40pitrousetmessageid: <1289597080.96.0.9732660757.issue10401@psf.upfronthosting.co.za>
2010-11-12 21:24:29pitroulinkissue10401 messages
2010-11-12 21:24:29pitroucreate