Question

我正在尝试检测主线程繁忙时间的百分比，因此我可以在用户使用应用程序时记录该指标。目前，在答案here的帮助下，我能找到的最接近的是user_time中的basic_info，但是我怎么知道正在使用哪个线程以及它的主线程呢？那么从这里我如何知道该会话中有多少时间占应用程序总运行时间的百分比？

Answer 1

所以我设法使用以下方法解决了这个问题：

class MainThreadAnalyser {
    typealias SumTotal = (total: Double, elements: Double)

    private var threadPercentages = [Double]()

    private let timeIntervalSeconds: Double

    init(timeIntervalSeconds: Double) {
        self.timeIntervalSeconds = timeIntervalSeconds
        if #available(iOS 10.0, *) {
            self.startCPUMonitoring(timeIntervalSeconds: self.timeIntervalSeconds)
        }
    }

    func getAverageCpuUsage() -> Double? {
        let sumTotal = threadPercentages.reduce((total: 0, elements: 0)) { (sum, item) -> SumTotal in
            var result = sum
            if item > 0 {
                result.total += item
                result.elements += 1
            }

            return result
        }

        return sumTotal.elements > 0 ? sumTotal.total / sumTotal.elements : nil
    }

    @available(iOS 10.0, *)
    private func startCPUMonitoring(timeIntervalSeconds: Double) {
        Timer.scheduledTimer(withTimeInterval: timeIntervalSeconds, repeats: true) { [weak self] _ in
            guard let strongSelf = self else { return }
            if let cpuUsage = strongSelf.cpuUsage() {
                strongSelf.threadPercentages.append(cpuUsage)
            }
        }
    }

    private func cpuUsage() -> Double? {
        var kernReturn: kern_return_t
        var taskInfoCount: mach_msg_type_number_t

        taskInfoCount = mach_msg_type_number_t(TASK_INFO_MAX)
        var tinfo = [integer_t](repeating: 0, count: Int(taskInfoCount))

        kernReturn = task_info(mach_task_self_, task_flavor_t(TASK_BASIC_INFO), &tinfo, &taskInfoCount)
        if kernReturn != KERN_SUCCESS {
            return -1
        }

        var threadArray: thread_act_array_t? = UnsafeMutablePointer(mutating: [thread_act_t]())
        var threadCount: mach_msg_type_number_t = 0
        defer {
            if let threadArray = threadArray {
                vm_deallocate(mach_task_self_, vm_address_t(UnsafePointer(threadArray).pointee), vm_size_t(threadCount))
            }
        }

        kernReturn = task_threads(mach_task_self_, &threadArray, &threadCount)

        if kernReturn != KERN_SUCCESS {
            return -1
        }

        var totalCPU: Double?

        if let threadArray = threadArray {

            for index in 0 ..< Int(threadCount) {
                var threadInfoCount = mach_msg_type_number_t(THREAD_INFO_MAX)
                var thinfo = [integer_t](repeating: 0, count: Int(threadInfoCount))
                kernReturn = thread_info(threadArray[index], thread_flavor_t(THREAD_BASIC_INFO),
                                 &thinfo, &threadInfoCount)
                if kernReturn != KERN_SUCCESS {
                    return -1
                }

                if index == 0 {
                    let cpuUse = thinfo[4]
                    totalCPU = Double(cpuUse/10)

                }
            }
        }

        return totalCPU
    }
}

Answer 2

当应用程序处于前台时，主线程一直在使用。因此，您可以在applicationDidBecomeActive中安排计时器，并在applicationWillResignActive中使计时器无效，并随时获取累积的秒数。

检测使用主线程的时间百分比

2 个答案: