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Re: More precision about my new inventions of scalable algorithms..

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From "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com>
Newsgroups comp.programming.threads, comp.lang.c++
Subject Re: More precision about my new inventions of scalable algorithms..
Date Sat, 20 Feb 2021 12:46:28 -0800
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On 2/19/2021 11:50 PM, Bonita Montero wrote:
>> Ummm... I am not sure what you mean here. ...
> 
> Readers can hold the mutex as long as they want.
> And writers can do the opposite.

Indeed. But you snipped my relevant part.


> So they can prevent other writers or readers to lock the mutex.
> So RW-locks are never starvation-free.

Let me manually quote what I wrote. Its important because the type of 
starvation your are talking about is very different than the usual meaning.

Chris M. Thomasson wrote:
_________________________________
[...]
The type of starvation I am talking about is when reader activity is so 
frequent that writers just can't seem to get in. Even if the reader 
critical sections are short. Every time a writer wants to get in, 
several readers jump in line. Its all about reader or writer priority, a 
lot of rwmutex impls have that flaw. Sure a reader can hold the lock for 
an hour, okay. Well, writers cannot get in for an hour. That's perfectly 
normal. This is not the same type of starvation I am referring to...
_________________________________


Starvation on a rw mutex can occur when heavy reader activity actually 
starves out writers. Some implementations can actually prioritize reads, 
or writes. Some implementations have reader preference by design. So, 
starvation can occur when frequent readers prevent writers from 
acquiring write access. In other words, writers spend most of their time 
tying and failing to acquire the mutex. This is why its important to be 
very careful when one is implementing a rwmutex. I linked you to an 
algorithm I invented that is loop-free. It fairly alternates between 
batches of readers and writers. So, readers can never starve out 
writers, even during massive reader activity, and vise versa.

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Thread

More precision about my new inventions of scalable algorithms.. Amine Moulay Ramdane <aminer68@gmail.com> - 2021-02-18 11:07 -0800
  Re: More precision about my new inventions of scalable algorithms.. Bonita Montero <Bonita.Montero@gmail.com> - 2021-02-19 23:27 +0100
    Re: More precision about my new inventions of scalable algorithms.. "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2021-02-19 14:48 -0800
      Re: More precision about my new inventions of scalable algorithms.. Bonita Montero <Bonita.Montero@gmail.com> - 2021-02-20 00:01 +0100
        Re: More precision about my new inventions of scalable algorithms.. "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2021-02-19 15:17 -0800
          Re: More precision about my new inventions of scalable algorithms.. Bonita Montero <Bonita.Montero@gmail.com> - 2021-02-20 08:50 +0100
            Re: More precision about my new inventions of scalable algorithms.. "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2021-02-20 12:46 -0800
              Re: More precision about my new inventions of scalable algorithms.. "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2021-02-20 12:52 -0800
              Re: More precision about my new inventions of scalable algorithms.. Bonita Montero <Bonita.Montero@gmail.com> - 2021-02-21 17:16 +0100
                Re: More precision about my new inventions of scalable algorithms.. Richard Damon <Richard@Damon-Family.org> - 2021-02-21 13:15 -0500
                Re: More precision about my new inventions of scalable algorithms.. Bonita Montero <Bonita.Montero@gmail.com> - 2021-02-21 19:58 +0100
                Re: More precision about my new inventions of scalable algorithms.. Richard Damon <Richard@Damon-Family.org> - 2021-02-21 15:58 -0500
                Re: More precision about my new inventions of scalable algorithms.. "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2021-02-21 14:35 -0800
                Re: More precision about my new inventions of scalable algorithms.. Bonita Montero <Bonita.Montero@gmail.com> - 2021-02-22 06:54 +0100
                Re: More precision about my new inventions of scalable algorithms.. "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2021-02-21 22:00 -0800
                Re: More precision about my new inventions of scalable algorithms.. Bonita Montero <Bonita.Montero@gmail.com> - 2021-02-22 07:40 +0100
                Re: More precision about my new inventions of scalable algorithms.. Bonita Montero <Bonita.Montero@gmail.com> - 2021-02-22 09:20 +0100
                Re: More precision about my new inventions of scalable algorithms.. "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2021-02-22 14:54 -0800
                Re: More precision about my new inventions of scalable algorithms.. Bonita Montero <Bonita.Montero@gmail.com> - 2021-02-23 08:38 +0100
                Re: More precision about my new inventions of scalable algorithms.. "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2021-02-23 00:25 -0800
                Re: More precision about my new inventions of scalable algorithms.. Bonita Montero <Bonita.Montero@gmail.com> - 2021-02-23 20:17 +0100
                Re: More precision about my new inventions of scalable algorithms.. "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2021-02-23 11:29 -0800
                Re: More precision about my new inventions of scalable algorithms.. Bonita Montero <Bonita.Montero@gmail.com> - 2021-02-24 18:20 +0100
                Re: More precision about my new inventions of scalable algorithms.. "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2021-02-25 01:49 -0800
                Re: More precision about my new inventions of scalable algorithms.. "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2021-02-23 14:13 -0800
                Re: More precision about my new inventions of scalable algorithms.. "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2021-02-23 14:14 -0800
                Re: More precision about my new inventions of scalable algorithms.. Richard Damon <Richard@Damon-Family.org> - 2021-02-23 16:51 -0500
                Re: More precision about my new inventions of scalable algorithms.. Bonita Montero <Bonita.Montero@gmail.com> - 2021-02-24 18:22 +0100
                Re: More precision about my new inventions of scalable algorithms.. Richard Damon <Richard@Damon-Family.org> - 2021-02-24 13:28 -0500
                Re: More precision about my new inventions of scalable algorithms.. "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2021-02-24 17:16 -0800
                Re: More precision about my new inventions of scalable algorithms.. Bonita Montero <Bonita.Montero@gmail.com> - 2021-02-25 07:08 +0100
                Re: More precision about my new inventions of scalable algorithms.. "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2021-02-24 23:39 -0800
                Re: More precision about my new inventions of scalable algorithms.. Bonita Montero <Bonita.Montero@gmail.com> - 2021-02-25 09:49 +0100
                Re: More precision about my new inventions of scalable algorithms.. "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2021-02-25 01:05 -0800
                Re: More precision about my new inventions of scalable algorithms.. Bonita Montero <Bonita.Montero@gmail.com> - 2021-02-25 11:43 +0100
                Re: More precision about my new inventions of scalable algorithms.. "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2021-02-25 03:09 -0800
                Re: More precision about my new inventions of scalable algorithms.. "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2021-02-25 03:10 -0800
                Re: More precision about my new inventions of scalable algorithms.. "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2021-02-24 23:43 -0800
                Re: More precision about my new inventions of scalable algorithms.. Bonita Montero <Bonita.Montero@gmail.com> - 2021-02-22 06:52 +0100
                Re: More precision about my new inventions of scalable algorithms.. "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2021-02-21 22:10 -0800
                Re: More precision about my new inventions of scalable algorithms.. "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2021-02-21 21:47 -0800
                Re: More precision about my new inventions of scalable algorithms.. Bonita Montero <Bonita.Montero@gmail.com> - 2021-02-22 06:51 +0100
                Re: More precision about my new inventions of scalable algorithms.. "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2021-02-21 22:01 -0800
        Re: More precision about my new inventions of scalable algorithms.. "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2021-02-19 15:32 -0800
          Re: More precision about my new inventions of scalable algorithms.. "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2021-02-19 15:37 -0800
      Re: More precision about my new inventions of scalable algorithms.. Amine Moulay Ramdane <aminer68@gmail.com> - 2021-02-19 15:14 -0800

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