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Groups > comp.lang.c++ > #120878
| From | "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> |
|---|---|
| Newsgroups | comp.lang.c++ |
| Subject | Re: smrproxy v2 |
| Date | 2024-11-09 13:51 -0800 |
| Organization | A noiseless patient Spider |
| Message-ID | <vgolgt$3vr0c$3@dont-email.me> (permalink) |
| References | (17 earlier) <vftnga$27k8k$2@dont-email.me> <vg9l7u$q3ee$3@dont-email.me> <vgafnd$uhgj$1@dont-email.me> <vgaki9$vn6q$1@dont-email.me> <vgbbkd$141v1$1@dont-email.me> |
On 11/4/2024 12:42 PM, Chris M. Thomasson wrote:
> On 11/4/2024 6:09 AM, Muttley@DastartdlyHQ.org wrote:
>> On Mon, 4 Nov 2024 07:46:37 -0500
>> jseigh <jseigh_es00@xemaps.com> boring babbled:
>>> On 11/4/24 00:14, Chris M. Thomasson wrote:
>>>> On 10/30/2024 9:39 AM, jseigh wrote:
>>>>> On 10/29/24 18:05, Chris M. Thomasson wrote:
>>>>>> On 10/28/2024 9:41 PM, Chris M. Thomasson wrote:
>>>>>
>>>>>>
>>>>>> Ahhh, if you are using an async membar in your upcoming C++ version,
>>>>>> then it would be fine. No problem. A compiler fence ala
>>>>>> atomic_signal_fence, and the the explicit release, well, it will
>>>>>> work. I don't see why it would not work.
>>>>>>
>>>>>> For some reason, I thought you were going to not use an async membar
>>>>>> in your C++ version. Sorry. However, it still would be fun to test
>>>>>> against... ;^)
>>>>>
>>>>> The C version has both versions. The C++ version does only the
>>>>> async member version. But I'm not publishing that code so it's
>>>>> a moot point.
>>>>
>>>> I got side tracked with more heavy math. The problem with C++ code that
>>>> uses an async memory barrier is that its automatically rendered into a
>>>> non-portable state... Yikes! Imvvvvvho, C/C++ should think about
>>>> including them in some future standard. It would be nice. Well, for us
>>>> at least! ;^)
>>>
>>> That's never going to happen. DWCAS has been around for more than
>>> 50 years and c++ doesn't support that and probably never will.
>>> You can't write lock-free queues that are ABA free and
>>> are performant without that. So async memory barriers won't
>>> happen any time soon either.
>>>
>>> Long term I think c++ will fade into irrelevance along with
>>> all the other programming languages based on an imperfect
>>> knowledge of concurrency, which is basically all of them
>>> right now.
>>
>> Given most concurrent operating systems are written in these "imperfect"
>> languages how does that square with your definition? And how would your
>> perfect language run on them?
>>
>> Anyway, concurrency is the job of the OS, not the language. C++
>> threading is
>> just a wrapper around pthreads on *nix and windows threads on Windows.
>> The
>> language just needs an interface to the underlying OS functionality,
>> it should
>> not try and implement the functionality itself as it'll always be a hack.
>>
>
> A start would be C++ having an "always lock free" CAS for two contiguous
> words on systems that support it, yes, even 64 bit. ala:
>
> struct anchor {
> word a;
> word b;
> };
Even better:
struct anchor {
void* a;
word b;
};
where sizeof(void*) = sizeof(word)... ;^)
>
> cmpxchg8b for x86, cmpxchg16b for x64, ect...
>
> https://www.felixcloutier.com/x86/cmpxchg8b:cmpxchg16b
>
>
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smrproxy v2 jseigh <jseigh_es00@xemaps.com> - 2024-10-17 08:10 -0400
Re: smrproxy v2 "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-10-17 13:10 -0700
Re: smrproxy v2 jseigh <jseigh_es00@xemaps.com> - 2024-10-17 17:08 -0400
Re: smrproxy v2 "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-10-17 16:40 -0700
Re: smrproxy v2 "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-10-17 17:16 -0700
Re: smrproxy v2 "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-10-17 17:24 -0700
Re: smrproxy v2 jseigh <jseigh_es00@xemaps.com> - 2024-10-18 08:07 -0400
Re: smrproxy v2 "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-10-25 15:00 -0700
Re: smrproxy v2 jseigh <jseigh_es00@xemaps.com> - 2024-10-25 18:56 -0400
Re: smrproxy v2 "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-10-27 12:33 -0700
Re: smrproxy v2 jseigh <jseigh_es00@xemaps.com> - 2024-10-27 18:29 -0400
Re: smrproxy v2 "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-10-27 15:32 -0700
Re: smrproxy v2 jseigh <jseigh_es00@xemaps.com> - 2024-10-27 20:35 -0400
Re: smrproxy v2 "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-10-27 21:02 -0700
Re: smrproxy v2 jseigh <jseigh_es00@xemaps.com> - 2024-10-28 07:45 -0400
Re: smrproxy v2 "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-10-28 14:57 -0700
Re: smrproxy v2 "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-10-28 15:09 -0700
Re: smrproxy v2 jseigh <jseigh_es00@xemaps.com> - 2024-10-28 21:17 -0400
Re: smrproxy v2 "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-10-28 21:35 -0700
Re: smrproxy v2 jseigh <jseigh_es00@xemaps.com> - 2024-10-29 07:23 -0400
Re: smrproxy v2 "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-10-29 14:51 -0700
Re: smrproxy v2 "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-10-28 21:38 -0700
Re: smrproxy v2 jseigh <jseigh_es00@xemaps.com> - 2024-10-29 07:27 -0400
Re: smrproxy v2 "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-10-29 14:56 -0700
Re: smrproxy v2 jseigh <jseigh_es00@xemaps.com> - 2024-10-30 12:36 -0400
Re: smrproxy v2 "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-11-01 12:20 -0700
Re: smrproxy v2 "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-10-28 21:41 -0700
Re: smrproxy v2 "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-10-29 15:05 -0700
Re: smrproxy v2 jseigh <jseigh_es00@xemaps.com> - 2024-10-30 12:39 -0400
Re: smrproxy v2 "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-11-03 21:14 -0800
Re: smrproxy v2 jseigh <jseigh_es00@xemaps.com> - 2024-11-04 07:46 -0500
Re: smrproxy v2 Muttley@DastartdlyHQ.org - 2024-11-04 14:09 +0000
Re: smrproxy v2 "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-11-04 12:42 -0800
Re: smrproxy v2 "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-11-09 13:51 -0800
Re: smrproxy v2 "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-12-12 00:43 -0800
Re: smrproxy v2 jseigh <jseigh_es00@xemaps.com> - 2024-12-12 07:29 -0500
Re: smrproxy v2 "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-12-12 13:55 -0800
Re: smrproxy v2 jseigh <jseigh_es00@xemaps.com> - 2024-12-12 19:48 -0500
Re: smrproxy v2 "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-12-25 20:36 -0800
Re: smrproxy v2 "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-10-27 21:08 -0700
Re: smrproxy v2 "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-10-27 21:09 -0700
Re: smrproxy v2 "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-10-27 21:13 -0700
Re: smrproxy v2 "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-10-28 22:02 -0700
Re: smrproxy v2 "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-10-29 23:40 -0700
Re: smrproxy v2 "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-10-29 23:42 -0700
Re: smrproxy v2 "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-10-29 23:53 -0700
Re: smrproxy v2 "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-10-29 23:54 -0700
Re: smrproxy v2 jseigh <jseigh_es00@xemaps.com> - 2024-10-30 12:43 -0400
Re: smrproxy v2 "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-11-02 13:50 -0700
Re: smrproxy v2 jseigh <jseigh_es00@xemaps.com> - 2024-11-21 15:17 -0500
Re: smrproxy v2 jseigh <jseigh_es00@xemaps.com> - 2024-11-23 11:10 -0500
Re: smrproxy v2 "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-11-23 13:31 -0800
Re: smrproxy v2 jseigh <jseigh_es00@xemaps.com> - 2024-11-23 17:12 -0500
Re: smrproxy v2 "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-11-23 17:46 -0800
Re: smrproxy v2 jseigh <jseigh_es00@xemaps.com> - 2024-11-24 15:14 -0500
Re: smrproxy v2 "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-11-24 15:19 -0800
Re: smrproxy v2 jseigh <jseigh_es00@xemaps.com> - 2024-11-24 19:09 -0500
Re: smrproxy v2 "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-11-24 16:37 -0800
Re: smrproxy v2 "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-11-24 16:48 -0800
Re: smrproxy v2 "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-11-24 16:47 -0800
Re: smrproxy v2 jseigh <jseigh_es00@xemaps.com> - 2024-11-25 06:31 -0500
Re: smrproxy v2 "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-11-25 14:12 -0800
Re: smrproxy v2 jseigh <jseigh_es00@xemaps.com> - 2024-11-27 10:29 -0500
Re: smrproxy v2 jseigh <jseigh_es00@xemaps.com> - 2024-12-09 13:34 -0500
Re: smrproxy v2 jseigh <jseigh_es00@xemaps.com> - 2024-12-11 07:13 -0500
Re: smrproxy v2 "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-12-11 16:22 -0800
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