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Some help needed

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I've developed a monitor-object like that of Java for C++ with some
improvements. The major improvement is that there's not only a spin
-loop for locking and unlocking but also for waiting on an event. In
this case you don't have to lock the mutex but supply a predicate on
a wait_poll-function and the code repeatedly tries to lock the mutex
polling and if it can lock the mutex it calls the predicate which
returns (or moves) a pair of a bool and the result-type.
Waiting to for a semaphore and or a event-object (Win32) in the kernel
can easily take from 1.000 to 10.000 clock-cylces even when the call
immediately returns because the semaphore or event has been set before.
So there has to be a spin count with a reasonable relationship to this
waiting-inteval, f.e. spinning one tenth of the minimum interval being
spent in the kernel.
With my monitor-object I've taken the spincount recalculation-algorithm
from the glibc. And I'm also using the PAUSE-instruction. But I think
that the glibc induces to heavy cacheline-flipping by re-loading the
mutex-flags immediately after a single PAUSE-instruction. So I decided
to loop PAUSE several times and to take less spinning iterations there-
fore.
To get a reasonable number of PAUSE-spinnings I need the time PAUSE
takes on different processors. On my CPU PAUSE halts the pipe only
for about for 0,78 nanoseconds, which is about 3,25 clock-cycles in
average. I've written a short progam tha repeatedly PAUSEs and takes
the aveage time. I want to encourage you to compile the code on your
machine and give me the PAUSE-timing it outputs here.

This is the code:

#include <iostream>
#include <chrono>
#include <cstddef>
#include <cstdint>
#include <immintrin.h>

using namespace std;
using namespace chrono;

int main( int argc, char **argv )
{
	static uint64_t const PAUSE_ROUNDS = 1'000'000'000;
	auto start = high_resolution_clock::now();
	for( uint64_t i = PAUSE_ROUNDS; i; --i )
		_mm_pause();
	double ns = (int64_t)duration_cast<nanoseconds>( 
high_resolution_clock::now() - start ).count() / (double)PAUSE_ROUNDS;
	cout << ns << endl;
}

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Some help needed Bonita Montero <Bonita.Montero@gmail.com> - 2021-09-25 16:41 +0200
  Re: Some help needed Paavo Helde <myfirstname@osa.pri.ee> - 2021-09-25 19:51 +0300
    Re: Some help needed Bonita Montero <Bonita.Montero@gmail.com> - 2021-09-25 19:01 +0200
    Re: Some help needed Branimir Maksimovic <branimir.maksimovic@gmail.com> - 2021-09-25 17:20 +0000
  Re: Some help needed Bo Persson <bo@bo-persson.se> - 2021-09-25 19:05 +0200
    Re: Some help needed Bonita Montero <Bonita.Montero@gmail.com> - 2021-09-25 19:14 +0200
    Re: Some help needed Branimir Maksimovic <branimir.maksimovic@gmail.com> - 2021-09-25 17:33 +0000
  Re: Some help needed Branimir Maksimovic <branimir.maksimovic@gmail.com> - 2021-09-25 17:15 +0000
    Re: Some help needed Bonita Montero <Bonita.Montero@gmail.com> - 2021-09-25 19:16 +0200
      Re: Some help needed Branimir Maksimovic <branimir.maksimovic@gmail.com> - 2021-09-25 17:29 +0000
  Re: Some help needed Bonita Montero <Bonita.Montero@gmail.com> - 2021-09-26 07:26 +0200
    Re: Some help needed Branimir Maksimovic <branimir.maksimovic@gmail.com> - 2021-09-26 06:56 +0000
    Re: Some help needed - further help Bonita Montero <Bonita.Montero@gmail.com> - 2021-09-27 17:35 +0200
      Re: Some help needed - further help Bo Persson <bo@bo-persson.se> - 2021-09-27 19:29 +0200

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