Method purgeLoop

internal/caches/storage_memory.go:436–497

清理任务

()

// 清理任务
func (this *MemoryStorage) purgeLoop() {
	// 清理过期
	var purgeCount = this.policy.MemoryAutoPurgeCount
	if purgeCount <= 0 {
		purgeCount = 2000
	}
	_, _ = this.list.Purge(purgeCount, func(hash string) error {
		uintHash, err := strconv.ParseUint(hash, 10, 64)
		if err == nil {
			this.locker.Lock()
			delete(this.valuesMap, uintHash)
			this.locker.Unlock()
		}
		return nil
	})

	// LFU
	// 计算是否应该开启LFU清理
	var capacityBytes = this.policy.CapacityBytes()
	var startLFU = false

	var usedPercent = float32(this.TotalMemorySize()*100) / float32(capacityBytes)
	var lfuFreePercent = this.policy.MemoryLFUFreePercent
	if lfuFreePercent <= 0 {
		lfuFreePercent = 5
	}
	if capacityBytes > 0 {
		if lfuFreePercent < 100 {
			if usedPercent >= 100-lfuFreePercent {
				startLFU = true
			}
		}
	}

	if startLFU {
		var total, _ = this.list.Count()
		if total > 0 {
			var count = types.Int(math.Ceil(float64(total) * float64(lfuFreePercent*2) / 100))
			if count > 0 {
				// 限制单次清理的条数，防止占用太多系统资源
				if count > 2000 {
					count = 2000
				}

				// 这里不提示LFU，因为此事件将会非常频繁

				err := this.list.PurgeLFU(count, func(hash string) error {
					uintHash, err := strconv.ParseUint(hash, 10, 64)
					if err == nil {
						this.locker.Lock()
						delete(this.valuesMap, uintHash)
						this.locker.Unlock()
					}
					return nil
				})
				if err != nil {
					remotelogs.Warn("CACHE", "purge memory storage in LFU failed: "+err.Error())
				}