[Python-Dev] Remove own implementation for thread-local storage
Hi, python-dev. I'd propose removing code which I think out-of-date. CPython has provided the own implementation for thread-local storage (TLS) on Python/thread.c, it's used in the case which a platform has not supplied native TLS. However, currently all supported platforms (NT and pthreads) have provided native TLS and defined the Py_HAVE_NATIVE_TLS macro with unconditional in any case. If the code is removed, the new TLS API for PEP 539 won't have to care the reinitialization of the thread keys managed by the interpreter (i.e. PyThread_ReInitTLS function has been working for own implementation and will be no longer necessary for new API). Does anyone have a reason we should keep it? Regards, Masayuki ___ 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/archive%40mail-archive.com
Re: [Python-Dev] 64 bit units in PyLong
2017-07-03 6:52 GMT+02:00 Siyuan Ren : > The current PyLong implementation represents arbitrary precision integers in > units of 15 or 30 bits. I presume the purpose is to avoid overflow in > addition , subtraction and multiplication. But compilers these days offer > intrinsics that allow one to access the overflow flag, and to obtain the > result of 64 bit multiplication as a 128 bit number. The question is the performance. Is it fast? :-) You can try to write a patch and run a benchmark. See for example http://pyperformance.readthedocs.io/ for benchmarks. Victor ___ 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/archive%40mail-archive.com
Re: [Python-Dev] Remove own implementation for thread-local storage
I'm in favor of removing it. I know that it confused people many times, they look at this fallback and found an issue, whereas I'm not aware of any platform using this fallback anymore. Can you please write a PR just to remove this fallback? We can merge it and then check buildbots :-) So in the worst case, we can revert it. Victor 2017-07-03 9:32 GMT+02:00 Masayuki YAMAMOTO : > Hi, python-dev. > > I'd propose removing code which I think out-of-date. > CPython has provided the own implementation for thread-local storage (TLS) > on Python/thread.c, it's used in the case which a platform has not supplied > native TLS. However, currently all supported platforms (NT and pthreads) > have provided native TLS and defined the Py_HAVE_NATIVE_TLS macro with > unconditional in any case. > If the code is removed, the new TLS API for PEP 539 won't have to care the > reinitialization of the thread keys managed by the interpreter (i.e. > PyThread_ReInitTLS function has been working for own implementation and will > be no longer necessary for new API). Does anyone have a reason we should > keep it? > > Regards, > Masayuki > > ___ > 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/victor.stinner%40gmail.com > ___ 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/archive%40mail-archive.com
Re: [Python-Dev] Remove own implementation for thread-local storage
Also note that C11, MSVC and some Unix C compilers have built-in support for thread-local variables. Example: https://github.com/numba/numba/blob/master/numba/_random.c#L114-L119 Regards Antoine. On Mon, 3 Jul 2017 10:07:06 +0200 Victor Stinner wrote: > I'm in favor of removing it. I know that it confused people many > times, they look at this fallback and found an issue, whereas I'm not > aware of any platform using this fallback anymore. > > Can you please write a PR just to remove this fallback? We can merge > it and then check buildbots :-) So in the worst case, we can revert > it. > > Victor > > 2017-07-03 9:32 GMT+02:00 Masayuki YAMAMOTO : > > Hi, python-dev. > > > > I'd propose removing code which I think out-of-date. > > CPython has provided the own implementation for thread-local storage (TLS) > > on Python/thread.c, it's used in the case which a platform has not supplied > > native TLS. However, currently all supported platforms (NT and pthreads) > > have provided native TLS and defined the Py_HAVE_NATIVE_TLS macro with > > unconditional in any case. > > If the code is removed, the new TLS API for PEP 539 won't have to care the > > reinitialization of the thread keys managed by the interpreter (i.e. > > PyThread_ReInitTLS function has been working for own implementation and will > > be no longer necessary for new API). Does anyone have a reason we should > > keep it? > > > > Regards, > > Masayuki > > > > ___ > > 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/victor.stinner%40gmail.com > > ___ 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/archive%40mail-archive.com
Re: [Python-Dev] Remove own implementation for thread-local storage
Sadly, we only require C99 yet :-/ Victor 2017-07-03 10:19 GMT+02:00 Antoine Pitrou : > > Also note that C11, MSVC and some Unix C compilers have built-in support > for thread-local variables. Example: > https://github.com/numba/numba/blob/master/numba/_random.c#L114-L119 > > Regards > > Antoine. > > > On Mon, 3 Jul 2017 10:07:06 +0200 > Victor Stinner wrote: > >> I'm in favor of removing it. I know that it confused people many >> times, they look at this fallback and found an issue, whereas I'm not >> aware of any platform using this fallback anymore. >> >> Can you please write a PR just to remove this fallback? We can merge >> it and then check buildbots :-) So in the worst case, we can revert >> it. >> >> Victor >> >> 2017-07-03 9:32 GMT+02:00 Masayuki YAMAMOTO : >> > Hi, python-dev. >> > >> > I'd propose removing code which I think out-of-date. >> > CPython has provided the own implementation for thread-local storage (TLS) >> > on Python/thread.c, it's used in the case which a platform has not supplied >> > native TLS. However, currently all supported platforms (NT and pthreads) >> > have provided native TLS and defined the Py_HAVE_NATIVE_TLS macro with >> > unconditional in any case. >> > If the code is removed, the new TLS API for PEP 539 won't have to care the >> > reinitialization of the thread keys managed by the interpreter (i.e. >> > PyThread_ReInitTLS function has been working for own implementation and >> > will >> > be no longer necessary for new API). Does anyone have a reason we should >> > keep it? >> > >> > Regards, >> > Masayuki >> > >> > ___ >> > 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/victor.stinner%40gmail.com >> > > > > > ___ > 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/victor.stinner%40gmail.com ___ 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/archive%40mail-archive.com
[Python-Dev] Need help to review a test_nntplib enhancement:
Hi, Sometimes, for an unknown reason, test_nntplib fails randomly: http://bugs.python.org/issue19613 Martin Panter wrote a patch, but since I don't know how to reproduce the bug, I'm unable to test it. Moreover, I don't know nntplib nor test_nntplib, so I don't feel able to review it. Sadly, Martin doesn't feel confident enough in his patch neither, since again, he is unable to test it. As a result, the issue is stuck and the bug continues to occur sometimes on buildbots. Victor ___ 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/archive%40mail-archive.com
Re: [Python-Dev] Remove own implementation for thread-local storage
On 3 July 2017 at 20:02, Victor Stinner wrote: > Sadly, we only require C99 yet :-/ Handling fallbacks when shiny new features are unavailable is what autoconf is for, though :) The fact thread specific storage support made it directly into C11 makes me more confident in dropping our emulation, so +1 for investigating that *before* we finalize PEP 539. 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/archive%40mail-archive.com
Re: [Python-Dev] Remove own implementation for thread-local storage
>> I'd propose removing code which I think out-of-date. Already done! https://github.com/python/cpython/commit/aa0aa0492c5fffe750a26d2ab13737a1a6d7d63c (and no buildbot complained). Victor ___ 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/archive%40mail-archive.com
