2017年07月21日 4:52 GMT+02:00 Nick Coghlan <[email protected]>: > On 21 July 2017 at 12:44, Nick Coghlan <[email protected]> wrote: > > We can separately measure the cost of unmarshalling the code object: > > > > $ python3 -m perf timeit -s "import typing; from marshal import loads; > from > > importlib.util import cache_from_source; cache = > > cache_from_source(typing.__file__); data = open(cache, > 'rb').read()[12:]" > > "loads(data)" > > ..................... > > Mean +- std dev: 286 us +- 4 us > > Slight adjustment here, as the cost of locating the cached bytecode > and reading it from disk should really be accounted for in each > iteration: > > $ python3 -m perf timeit -s "import typing; from marshal import loads; > from importlib.util import cache_from_source" "cache = > cache_from_source(typing.__spec__.origin); data = open(cache, > 'rb').read()[12:]; loads(data)" > ..................... > Mean +- std dev: 337 us +- 8 us > > That will have a bigger impact when loading from spinning disk or a > network drive, but it's fairly negligible when loading from a local > SSD or an already primed filesystem cache. > > Cheers, > Nick. > > -- > Nick Coghlan | [email protected] | Brisbane, Australia > Thanks for your tests, Nick. It's quite evident that the marshal code cannot improve the situation, so I regret from my proposal.
I took a look at the typing module, and there are some small things that can be optimized, but it'll not change the overall situation unfortunately. Code execution can be improved. :) However, it requires a massive amount of time experimenting... Bests, Cesare <https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail> Mail priva di virus. www.avast.com <https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail> <#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>
_______________________________________________ Python-Dev mailing list [email protected] https://mail.python.org/mailman/listinfo/python-dev Unsubscribe: https://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com