tvl-depot/users/wpcarro/go/channels.go
Vincent Ambo 019f8fd211 subtree(users/wpcarro): docking briefcase at '24f5a642'
git-subtree-dir: users/wpcarro
git-subtree-mainline: 464bbcb15c
git-subtree-split: 24f5a642af
Change-Id: I6105b3762b79126b3488359c95978cadb3efa789
2021-12-14 02:15:47 +03:00

81 lines
1.4 KiB
Go

package main
import (
"fmt"
"math/rand"
"sync"
"sync/atomic"
)
type readMsg struct {
key int
sender chan int
}
type writeMsg struct {
key int
value int
sender chan bool
}
func main() {
fmt.Println("Hello, go.")
var readOps uint64
var writeOps uint64
var wg sync.WaitGroup
reads := make(chan readMsg)
writes := make(chan writeMsg)
go func() {
state := make(map[int]int)
for {
select {
case msg := <-reads:
msg.sender <- state[msg.key]
case msg := <-writes:
state[msg.key] = msg.value
msg.sender <- true
}
}
}()
// Reads
for i := 0; i < 100; i += 1 {
go func() {
wg.Add(1)
defer wg.Done()
for j := 0; j < 100; j += 1 {
msg := readMsg{
key: rand.Intn(5),
sender: make(chan int)}
reads <- msg
val := <-msg.sender
fmt.Printf("Received %d.\n", val)
atomic.AddUint64(&readOps, 1)
}
}()
}
// Writes
for i := 0; i < 100; i += 1 {
go func() {
wg.Add(1)
defer wg.Done()
for j := 0; j < 100; j += 1 {
msg := writeMsg{
key: rand.Intn(5),
value: rand.Intn(10),
sender: make(chan bool)}
writes <- msg
<-msg.sender
fmt.Printf("Set %d as %d in state\n", msg.key, msg.value)
atomic.AddUint64(&writeOps, 1)
}
}()
}
wg.Wait()
fmt.Printf("Read ops: %d\tWrite ops: %d\n", atomic.LoadUint64(&readOps), atomic.LoadUint64(&writeOps))
}