aarzilli

Under the assumption that the range-over-function proposal is accepted and that the following code:

for x := range seq(3) {
	fmt.Println(x)
}

compiles equivalently to:

seq(3)(func(x int) bool {

fmt.Println(x)

aarzilli

package main

import (
	"fmt"
	"reflect"
)

type Bstruct struct {
	n float64
}

aarzilli

#include <stdio.h>
#include <pthread.h>

int N = 100000;
//int N = 20;

pthread_mutex_t ping_lock = PTHREAD_MUTEX_INITIALIZER, pong_lock = PTHREAD_MUTEX_INITIALIZER;
pthread_cond_t ping_cond, pong_cond;
pthread_t ping_thread, pong_thread;
int can_ping = 1, can_pong = 0;

aarzilli

package main

import (
	"runtime"
	"runtime/pprof"
	_ "runtime/trace"
	"fmt"
	"time"
	"os"
)

aarzilli

append.go:29 0x454e8d main._Append
append.go:29 0x454e95 main._Append
append.go:29 0x4550ad main._Append
append.go:29 0x4550b5 main._Append
chans.go:412 0x48c4e2 main.TestReadAll
chans.go:412 0x48c4e4 main.TestReadAll
chans.go:412 0x48c7c9 main.TestMerge
chans.go:412 0x48c7ce main.TestMerge
chans.go:412 0x48c912 main.TestMerge
chans.go:412 0x48c914 main.TestMerge

aarzilli

Proposal: runtime: allow N goroutines to be simultaneously locked to the same OS thread

Summary

The aim of this proposal is to extend the LockOSThread mechanism so that it is possible to create a N:1 association between N goroutines and 1 OS thread, by adding the following function to the runtime package

func LockToRecvOSThread[T any](ch <- chan T)

When LockToRecvOSThread is called the calling goroutine will be locked to the same thread as the goroutine receiving on ch, which is assumed to be already locked to a OS thread.

aarzilli

package main

import (
	"bufio"
	"bytes"
	"encoding/json"
	"fmt"
	"io"
	"io/ioutil"
	"net/http"

aarzilli

// This requires tip of Go master branch for 1.18; `gotip` is a great tool to
// use.
//

// Run benchmark with
// $ gotip test -bench=. <filename>
package main

import (
	"math/rand"

aarzilli

package main

import (
	"fmt"
	"runtime"
)

var globalvar1 = 0
var globalvar2 = 0

aarzilli

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