Go by Example: Worker Pools

Bu misolda goroutinalar va kanallar yordamida ishchi hovuzini qanday amalga oshirishni ko’rib chiqamiz.

 
package main
 
import (
    "fmt"
    "time"
)

Quyida ishchi, uning bir nechta parallel nusxalarini ishga tushiramiz. Bu ishchilar jobs kanalida ish qabul qiladi va mos keladigan natijalarni results ga yuboradi. Resurs talab qiladigan vazifani simulyatsiya qilish uchun har bir ish uchun bir soniya uxlaymiz.

 
func worker(id int, jobs <-chan int, results chan<- int) {
    for j := range jobs {
        fmt.Println("worker", id, "started  job", j)
        time.Sleep(time.Second)
        fmt.Println("worker", id, "finished job", j)
        results <- j * 2
    }
}
 
func main() {

Ishchilar hovuzimizdan foydalanish uchun ularga ish yuborishimiz va natijalarini yig’ishimiz kerak. Buning uchun 2 ta kanal yaratamiz.

 
    const numJobs = 5
    jobs := make(chan int, numJobs)
    results := make(chan int, numJobs)

Bu 3 ta ishchini ishga tushiradi, ular hozircha ish yo’qligi sababli dastlab bloklangan bo’ladi.

 
    for w := 1; w <= 3; w++ {
        go worker(w, jobs, results)
    }

Bu yerda 5 ta jobs yuboramiz va keyin ishlarimiz shu bilan tugaganini bildirish uchun o’sha kanalni close qilamiz.

 
    for j := 1; j <= numJobs; j++ {
        jobs <- j
    }
    close(jobs)

Nihoyat ishning barcha natijalarini yig’amiz. Bu shuningdek ishchi goroutinalar tugaganligini ham ta’minlaydi. Bir nechta goroutinani kutishning muqobil usuli WaitGroup dan foydalanishdir.

 
    for a := 1; a <= numJobs; a++ {
        <-results
    }
}

Ishlayotgan dasturimiz 5 ta ishning turli ishchilar tomonidan bajarilayotganini ko’rsatadi. Dastur jami taxminan 5 soniyalik ish bajarishiga qaramay, faqat taxminan 2 soniya vaqt oladi, chunki 3 ta ishchi parallel ishlaydi.

 
$ time go run worker-pools.go 
worker 1 started  job 1
worker 2 started  job 2
worker 3 started  job 3
worker 1 finished job 1
worker 1 started  job 4
worker 2 finished job 2
worker 2 started  job 5
worker 3 finished job 3
worker 1 finished job 4
worker 2 finished job 5
 
real    0m2.358s

Keyingi misol: .

mualliflar: Mark McGranaghan va Eli Bendersky | tarjima: @elchintoyirov | manba | litsenziya