Thanks, Nick -- that's interesting. I just saw the extra JUMP_FORWARD and JUMP_ABSOLUTE instructions on my commute home (I guess those are something Python 3.x optimizes away).
VERY strangely, on Windows Python 2.7 is faster! Comparing 64-bit Python 2.7.12 against Python 3.5.3 on my Windows 10 laptop: * Python 2.7.12: 4.088s * Python 3.5.3: 5.792s I'm pretty sure MSVC/Windows doesn't support computed gotos, but that doesn't explain why 3.5 is so much faster than 2.7 on Mac. I have yet to try it on Linux. -Ben On Tue, Jul 18, 2017 at 9:35 PM, Nick Coghlan <ncogh...@gmail.com> wrote: > On 19 July 2017 at 02:18, Antoine Pitrou <solip...@pitrou.net> wrote: > > On Tue, 18 Jul 2017 12:03:36 -0400 > > Ben Hoyt <benh...@gmail.com> wrote: > >> The program is a pentomino puzzle solver, and it works via code > generation, > >> generating a ton of nested "if" statements, so I believe it's exercising > >> the Python bytecode interpreter heavily. > > > > A first step would be to see if the generated bytecode has changed > > substantially. > > Scanning over them, the Python 2.7 bytecode appears to have many more > JUMP_FORWARD and JUMP_ABSOLUTE opcodes than appear in the 3.6 version > (I didn't dump them into a Counter instance to tally them properly > though, since 2.7's dis module is missing the structured opcode > iteration APIs). > > With the shift to wordcode, the overall size of the bytecode is also > significantly *smaller*: > > >>> len(co.co_consts[0].co_code) # 2.7 > 14427 > > >>> len(co.co_consts[0].co_code) # 3.6 > 11850 > > However, I'm not aware of any Python profilers that currently offer > opcode level profiling - the closest would probably be VMProf's JIT > profiling, and that aspect of VMProf is currently PyPy specific > (although could presumably be extended to CPython 3.6+ by way of the > opcode evaluation hook). > > Cheers, > Nick. > > -- > Nick Coghlan | ncogh...@gmail.com | Brisbane, Australia > _______________________________________________ > Python-Dev mailing list > Python-Dev@python.org > https://mail.python.org/mailman/listinfo/python-dev > Unsubscribe: https://mail.python.org/mailman/options/python-dev/ > benhoyt%40gmail.com >
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