Question

我正在尝试以编程方式随时检索我的iPhone应用程序正在使用的内存量。是的我知道ObjectAlloc / Leaks。我对这些不感兴趣，只知道是否可以编写一些代码并获取正在使用的字节数并通过NSLog报告。

感谢。

Answer 1

要获取应用程序正在使用的实际内存字节数，您可以执行类似下面的示例。但是，您真的应该熟悉各种分析工具，以及它们旨在让您更好地了解使用情况。

#import <mach/mach.h>

// ...

void report_memory(void) {
  struct task_basic_info info;
  mach_msg_type_number_t size = TASK_BASIC_INFO_COUNT;
  kern_return_t kerr = task_info(mach_task_self(),
                                 TASK_BASIC_INFO,
                                 (task_info_t)&info,
                                 &size);
  if( kerr == KERN_SUCCESS ) {
    NSLog(@"Memory in use (in bytes): %lu", info.resident_size);
    NSLog(@"Memory in use (in MiB): %f", ((CGFloat)info.resident_size / 1048576));
  } else {
    NSLog(@"Error with task_info(): %s", mach_error_string(kerr));
  }
}

info.virtual_size结构中还有一个字段，它将为您提供可用虚拟内存的字节数（或在任何情况下分配给您的应用程序的内存作为潜在的虚拟内存）。 pgb链接到的代码将为您提供设备可用的内存量以及它的内存类型。

Answer 2

TASK_BASIC_INFO的标题说：

/* Don't use this, use MACH_TASK_BASIC_INFO instead */

以下是使用MACH_TASK_BASIC_INFO的版本：

void report_memory(void)
{
    struct mach_task_basic_info info;
    mach_msg_type_number_t size = MACH_TASK_BASIC_INFO_COUNT;
    kern_return_t kerr = task_info(mach_task_self(),
                                   MACH_TASK_BASIC_INFO,
                                   (task_info_t)&info,
                                   &size);
    if( kerr == KERN_SUCCESS ) {
        NSLog(@"Memory in use (in bytes): %u", info.resident_size);
    } else {
        NSLog(@"Error with task_info(): %s", mach_error_string(kerr));
    }
}

Answer 3

这里增强了report_memory（）以快速显示NSLog（）中的泄漏状态。

void report_memory(void) {
    static unsigned last_resident_size=0;
    static unsigned greatest = 0;
    static unsigned last_greatest = 0;

    struct task_basic_info info;
    mach_msg_type_number_t size = sizeof(info);
    kern_return_t kerr = task_info(mach_task_self(),
                               TASK_BASIC_INFO,
                               (task_info_t)&info,
                               &size);
    if( kerr == KERN_SUCCESS ) {
        int diff = (int)info.resident_size - (int)last_resident_size;
        unsigned latest = info.resident_size;
        if( latest > greatest   )   greatest = latest;  // track greatest mem usage
        int greatest_diff = greatest - last_greatest;
        int latest_greatest_diff = latest - greatest;
        NSLog(@"Mem: %10u (%10d) : %10d :   greatest: %10u (%d)", info.resident_size, diff,
          latest_greatest_diff,
          greatest, greatest_diff  );
    } else {
        NSLog(@"Error with task_info(): %s", mach_error_string(kerr));
    }
    last_resident_size = info.resident_size;
    last_greatest = greatest;
}

Answer 4

快速解决Jason Coco的回答：

func reportMemory() {
    let name = mach_task_self_
    let flavor = task_flavor_t(TASK_BASIC_INFO)
    let basicInfo = task_basic_info()
    var size: mach_msg_type_number_t = mach_msg_type_number_t(sizeofValue(basicInfo))
    let pointerOfBasicInfo = UnsafeMutablePointer<task_basic_info>.alloc(1)

    let kerr: kern_return_t = task_info(name, flavor, UnsafeMutablePointer(pointerOfBasicInfo), &size)
    let info = pointerOfBasicInfo.move()
    pointerOfBasicInfo.dealloc(1)

    if kerr == KERN_SUCCESS {
        print("Memory in use (in bytes): \(info.resident_size)")
    } else {
        print("error with task info(): \(mach_error_string(kerr))")
    }
}

Answer 5

已在2019年7月1日在Mojave 10.4.6的Xcode 11上进行了测试。

所有先前的答案均返回错误的结果。

这是如何获得苹果公司的奎因（Quinn）“爱斯基摩人”（The Eskimo！）所写的期望值。

这将使用phys_footprint中的 Darwin > Mach > task_info 变量，并且与Xcode的Debug导航器中的内存条中的值紧密匹配。

返回的值以字节为单位。

https://forums.developer.apple.com/thread/105088#357415

原始代码如下。

func memoryFootprint() -> mach_vm_size_t? { // The `TASK_VM_INFO_COUNT` and `TASK_VM_INFO_REV1_COUNT` macros are too // complex for the Swift C importer, so we have to define them ourselves. let TASK_VM_INFO_COUNT = mach_msg_type_number_t(MemoryLayout<task_vm_info_data_t>.size / MemoryLayout<integer_t>.size) let TASK_VM_INFO_REV1_COUNT = mach_msg_type_number_t(MemoryLayout.offset(of: \task_vm_info_data_t.min_address)! / MemoryLayout<integer_t>.size) var info = task_vm_info_data_t() var count = TASK_VM_INFO_COUNT let kr = withUnsafeMutablePointer(to: &info) { infoPtr in infoPtr.withMemoryRebound(to: integer_t.self, capacity: Int(count)) { intPtr in task_info(mach_task_self_, task_flavor_t(TASK_VM_INFO), intPtr, &count) } } guard kr == KERN_SUCCESS, count >= TASK_VM_INFO_REV1_COUNT else { return nil } return info.phys_footprint }

稍加修改即可创建一个类级别的Swift方法集，从而可以轻松返回实际字节和以MB为单位的格式化输出以供显示。我将其用作自动UITest套件的一部分，以记录在同一测试的多次迭代之前和之后使用的内存，以查看是否有潜在的泄漏或分配需要研究。

// Created by Alex Zavatone on 8/1/19. // class Memory: NSObject { // From Quinn the Eskimo at Apple. // https://forums.developer.apple.com/thread/105088#357415 class func memoryFootprint() -> Float? { // The `TASK_VM_INFO_COUNT` and `TASK_VM_INFO_REV1_COUNT` macros are too // complex for the Swift C importer, so we have to define them ourselves. let TASK_VM_INFO_COUNT = mach_msg_type_number_t(MemoryLayout<task_vm_info_data_t>.size / MemoryLayout<integer_t>.size) let TASK_VM_INFO_REV1_COUNT = mach_msg_type_number_t(MemoryLayout.offset(of: \task_vm_info_data_t.min_address)! / MemoryLayout<integer_t>.size) var info = task_vm_info_data_t() var count = TASK_VM_INFO_COUNT let kr = withUnsafeMutablePointer(to: &info) { infoPtr in infoPtr.withMemoryRebound(to: integer_t.self, capacity: Int(count)) { intPtr in task_info(mach_task_self_, task_flavor_t(TASK_VM_INFO), intPtr, &count) } } guard kr == KERN_SUCCESS, count >= TASK_VM_INFO_REV1_COUNT else { return nil } let usedBytes = Float(info.phys_footprint) return usedBytes } class func formattedMemoryFootprint() -> String { let usedBytes: UInt64? = UInt64(self.memoryFootprint() ?? 0) let usedMB = Double(usedBytes ?? 0) / 1024 / 1024 let usedMBAsString: String = "\(usedMB)MB" return usedMBAsString } }

享受！

注意：进取的编码人员可能希望向该类添加静态格式化程序，以便usedMBAsString仅返回2个有效的小数位。

Answer 6

Swift 3.1 （截至2017年8月8日）

func getMemory() {

    var taskInfo = mach_task_basic_info()
    var count = mach_msg_type_number_t(MemoryLayout<mach_task_basic_info>.size)/4
    let kerr: kern_return_t = withUnsafeMutablePointer(to: &taskInfo) {
        $0.withMemoryRebound(to: integer_t.self, capacity: 1) {
            task_info(mach_task_self_, task_flavor_t(MACH_TASK_BASIC_INFO), $0, &count)
        }
    }
    if kerr == KERN_SUCCESS {
        let usedMegabytes = taskInfo.resident_size/(1024*1024)
        print("used megabytes: \(usedMegabytes)")
    } else {
        print("Error with task_info(): " +
            (String(cString: mach_error_string(kerr), encoding: String.Encoding.ascii) ?? "unknown error"))
    }

}

Answer 7

这是一个Swift 3版本：

func mach_task_self() -> task_t {
    return mach_task_self_
}

func getMegabytesUsed() -> Float? {
    var info = mach_task_basic_info()
    var count = mach_msg_type_number_t(MemoryLayout.size(ofValue: info) / MemoryLayout<integer_t>.size)
    let kerr = withUnsafeMutablePointer(to: &info) { infoPtr in
        return infoPtr.withMemoryRebound(to: integer_t.self, capacity: Int(count)) { (machPtr: UnsafeMutablePointer<integer_t>) in
            return task_info(
                mach_task_self(),
                task_flavor_t(MACH_TASK_BASIC_INFO),
                machPtr,
                &count
            )
        }
    }
    guard kerr == KERN_SUCCESS else {
        return nil
    }  
    return Float(info.resident_size) / (1024 * 1024)   
}

Answer 8

以下是正确答案：

```

func checkVariable() {
    let defaults = UserDefaults.standard
    if !defaults.bool(forKey: "XXXXXX.\
       (GlobalVariables.sharedinstance.circuitselectionne!)"){
       titre.text = "2,90€"
    } else {
       titre.text = "Démarrer la visite !  "
    }
}

```

Answer 9

Objective-C version:

size_t memoryFootprint()
{
    task_vm_info_data_t vmInfo;
    mach_msg_type_number_t count = TASK_VM_INFO_COUNT;
    kern_return_t result = task_info(mach_task_self(), TASK_VM_INFO, (task_info_t) &vmInfo, &count);
    if (result != KERN_SUCCESS)
        return 0;
    return static_cast<size_t>(vmInfo.phys_footprint);
}

以编程方式检索iPhone上的内存使用情况

9 个答案: