GoLang ants 高性能的 goroutine 池

ants

自动调度海量的 goroutines，复用 goroutines
定期清理过期的 goroutines，进一步节省资源
提供了大量有用的接口：任务提交、获取运行中的 goroutine 数量、动态调整 Pool 大小、释放 Pool、重启 Pool
优雅处理 panic，防止程序崩溃
资源复用，极大节省内存使用量；在大规模批量并发任务场景下比原生 goroutine 并发具有更高的性能
非阻塞机制

安装

go get -u github.com/panjf2000/ants/v2

package main

import (
	"fmt"
	"sync"
	"sync/atomic"
	"time"

	"github.com/panjf2000/ants/v2"
)

var sum int32

func myFunc(i interface{}) {
	n := i.(int32)
	atomic.AddInt32(&sum, n)
	fmt.Printf("run with %d\n", n)
}

func demoFunc() {
	time.Sleep(10 * time.Millisecond)
	fmt.Println("Hello World!")
}

func main() {
	defer ants.Release()

	runTimes := 1000

	// Use the common pool.
	var wg sync.WaitGroup
	syncCalculateSum := func() {
		demoFunc()
		wg.Done()
	}
	for i := 0; i < runTimes; i++ {
		wg.Add(1)
		_ = ants.Submit(syncCalculateSum)
	}
	wg.Wait()
	fmt.Printf("running goroutines: %d\n", ants.Running())
	fmt.Printf("finish all tasks.\n")

	// Use the pool with a function,
	// set 10 to the capacity of goroutine pool and 1 second for expired duration.
	p, _ := ants.NewPoolWithFunc(10, func(i interface{}) {
		myFunc(i)
		wg.Done()
	})
	defer p.Release()
	// Submit tasks one by one.
	for i := 0; i < runTimes; i++ {
		wg.Add(1)
		_ = p.Invoke(int32(i))
	}
	wg.Wait()
	fmt.Printf("running goroutines: %d\n", p.Running())
	fmt.Printf("finish all tasks, result is %d\n", sum)
}

Pool 配置

// Option represents the optional function.
type Option func(opts *Options)

// Options contains all options which will be applied when instantiating a ants pool.
type Options struct {
	// 方法的持续时间，超过该时间，会被清理掉
	ExpiryDuration time.Duration

	// 是否进行内存预分配
	PreAlloc bool

	// 最大阻塞任务数量。即池中 goroutine 数量已到池容量，且所有 goroutine 都处理繁忙状态，这时到来的任务会在阻塞列表等待。
    // 这个选项设置的是列表的最大长度。
    // 阻塞的任务数量达到这个值后，后续任务提交直接返回失败
	MaxBlockingTasks int

	// 池是否阻塞，默认阻塞。
    // 提交任务时，如果ants池中 goroutine 已到上限且全部繁忙，阻塞的池会将任务添加的阻塞列表等待（当然受限于阻塞列表长度，见上一个选项）。
    // 非阻塞的池直接返回失败
	Nonblocking bool

	// panic 处理。遇到 panic 会调用这里设置的处理函数
	PanicHandler func(interface{})

	// 指定日志记录器
	Logger Logger
}

// WithOptions accepts the whole options config.
func WithOptions(options Options) Option {
	return func(opts *Options) {
		*opts = options
	}
}

// WithExpiryDuration sets up the interval time of cleaning up goroutines.
func WithExpiryDuration(expiryDuration time.Duration) Option {
	return func(opts *Options) {
		opts.ExpiryDuration = expiryDuration
	}
}

// WithPreAlloc indicates whether it should malloc for workers.
func WithPreAlloc(preAlloc bool) Option {
	return func(opts *Options) {
		opts.PreAlloc = preAlloc
	}
}

// WithMaxBlockingTasks sets up the maximum number of goroutines that are blocked when it reaches the capacity of pool.
func WithMaxBlockingTasks(maxBlockingTasks int) Option {
	return func(opts *Options) {
		opts.MaxBlockingTasks = maxBlockingTasks
	}
}

// WithNonblocking indicates that pool will return nil when there is no available workers.
func WithNonblocking(nonblocking bool) Option {
	return func(opts *Options) {
		opts.Nonblocking = nonblocking
	}
}

// WithPanicHandler sets up panic handler.
func WithPanicHandler(panicHandler func(interface{})) Option {
	return func(opts *Options) {
		opts.PanicHandler = panicHandler
	}
}

// WithLogger sets up a customized logger.
func WithLogger(logger Logger) Option {
	return func(opts *Options) {
		opts.Logger = logger
	}
}

动态调整 goroutine 池容量

需要动态调整 goroutine 池容量可以通过调用Tune(int)：

1
2

pool.Tune(1000) // Tune its capacity to 1000
pool.Tune(100000) // Tune its capacity to 100000

释放 Pool

pool.Release()

重启 Pool

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// 只要调用 Reboot() 方法，就可以重新激活一个之前已经被销毁掉的池，并且投入使用。
pool.Reboot()