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Re: Interesting proposal...

From "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com>
Newsgroups comp.lang.c++
Subject Re: Interesting proposal...
Date 2023-12-14 21:59 -0800
Organization A noiseless patient Spider
Message-ID <ulgpvm$1ptdc$3@dont-email.me> (permalink)
References <ukr5o0$vo3f$1@dont-email.me> <ukrn9q$15keg$1@dont-email.me>

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On 12/6/2023 10:04 PM, Lynn McGuire wrote:
> On 12/6/2023 7:05 PM, Chris M. Thomasson wrote:
>> Context:
>>
>> https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0233r5.pdf
>>
>> SMR in std C++? Humm...
> 
> "A hazard pointer is a single-writer multi-reader pointer that can be 
> owned by at most one thread at any time. Only the owner of the hazard 
> pointer can set its value, while any number of threads may read its 
> value. A thread that is about to access dynamic objects optimistically 
> acquires ownership of a set of hazard pointer (typically one or two for 
> linked data structures) to protect such objects from being reclaimed. 
> The owner thread sets the value of a hazard pointer to point to an 
> object in order to indicate to concurrent threads — that may remove such 
> object — that the object is not yet safe to reclaim."
> 
> Looks cool.  Are these currently supported in cpu hardware or would cpus 
> have to be extended ?

No CPU extensions necessary. SMR is supported in current arch's. 
However, it can be made much better, aka avoiding that damn #StoreLoad 
style membar. One way is Joe's SMR+RCU hybrid proxy method...

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Thread

Interesting proposal... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-12-06 17:05 -0800
  Re: Interesting proposal... Lynn McGuire <lynnmcguire5@gmail.com> - 2023-12-07 00:04 -0600
    Re: Interesting proposal... Bonita Montero <Bonita.Montero@gmail.com> - 2023-12-07 07:57 +0100
      Re: Interesting proposal... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-12-08 12:17 -0800
        Re: Interesting proposal... Bonita Montero <Bonita.Montero@gmail.com> - 2023-12-09 19:11 +0100
          Re: Interesting proposal... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-12-09 12:54 -0800
    Re: Interesting proposal... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-12-14 21:59 -0800
  Re: Interesting proposal... jseigh <jseigh_es00@xemaps.com> - 2023-12-07 17:52 -0500
    Re: Interesting proposal... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-12-07 17:28 -0800
      Re: Interesting proposal... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-12-08 20:48 -0800
        Re: Interesting proposal... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-12-08 20:51 -0800
    Re: Interesting proposal... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-12-09 22:54 -0800

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