如何获取应用程序的 CPU 使用情况？这是完全可能的，因为 App Store 中有应用程序（Activity Monitor Touch）可以显示它。
3个回答
83
更新。这段代码对我有效：
更新2。thread_list有泄漏，因此添加了vm_deallocate。
#import <mach/mach.h>
#import <assert.h>
float cpu_usage()
{
kern_return_t kr;
task_info_data_t tinfo;
mach_msg_type_number_t task_info_count;
task_info_count = TASK_INFO_MAX;
kr = task_info(mach_task_self(), TASK_BASIC_INFO, (task_info_t)tinfo, &task_info_count);
if (kr != KERN_SUCCESS) {
return -1;
}
task_basic_info_t basic_info;
thread_array_t thread_list;
mach_msg_type_number_t thread_count;
thread_info_data_t thinfo;
mach_msg_type_number_t thread_info_count;
thread_basic_info_t basic_info_th;
uint32_t stat_thread = 0; // Mach threads
basic_info = (task_basic_info_t)tinfo;
// get threads in the task
kr = task_threads(mach_task_self(), &thread_list, &thread_count);
if (kr != KERN_SUCCESS) {
return -1;
}
if (thread_count > 0)
stat_thread += thread_count;
long tot_sec = 0;
long tot_usec = 0;
float tot_cpu = 0;
int j;
for (j = 0; j < (int)thread_count; j++)
{
thread_info_count = THREAD_INFO_MAX;
kr = thread_info(thread_list[j], THREAD_BASIC_INFO,
(thread_info_t)thinfo, &thread_info_count);
if (kr != KERN_SUCCESS) {
return -1;
}
basic_info_th = (thread_basic_info_t)thinfo;
if (!(basic_info_th->flags & TH_FLAGS_IDLE)) {
tot_sec = tot_sec + basic_info_th->user_time.seconds + basic_info_th->system_time.seconds;
tot_usec = tot_usec + basic_info_th->user_time.microseconds + basic_info_th->system_time.microseconds;
tot_cpu = tot_cpu + basic_info_th->cpu_usage / (float)TH_USAGE_SCALE * 100.0;
}
} // for each thread
kr = vm_deallocate(mach_task_self(), (vm_offset_t)thread_list, thread_count * sizeof(thread_t));
assert(kr == KERN_SUCCESS);
return tot_cpu;
}
- ivanzoid
17
1这是给应用程序的 CPU 使用情况还是整体 CPU 使用情况？ - Manish Ahuja
1感谢您的快速回复。有没有办法可以获取总体CPU使用情况？ - Manish Ahuja
4有没有一种方法可以获取进程ID的CPU使用率？ - Rukshan
2在微秒被累加的那一行，系统时间被加了两次。这可能应该改为用户时间+系统时间。 - George
对于线程计算，我会使用+=而不是让计算公式变得更长。在我看来，这样会更清晰。 - Julian
显示剩余12条评论
10
对于 Swift 3：
fileprivate func cpuUsage() -> Double {
var kr: kern_return_t
var task_info_count: mach_msg_type_number_t
task_info_count = mach_msg_type_number_t(TASK_INFO_MAX)
var tinfo = [integer_t](repeating: 0, count: Int(task_info_count))
kr = task_info(mach_task_self_, task_flavor_t(TASK_BASIC_INFO), &tinfo, &task_info_count)
if kr != KERN_SUCCESS {
return -1
}
var thread_list: thread_act_array_t? = UnsafeMutablePointer(mutating: [thread_act_t]())
var thread_count: mach_msg_type_number_t = 0
defer {
if let thread_list = thread_list {
vm_deallocate(mach_task_self_, vm_address_t(UnsafePointer(thread_list).pointee), vm_size_t(thread_count))
}
}
kr = task_threads(mach_task_self_, &thread_list, &thread_count)
if kr != KERN_SUCCESS {
return -1
}
var tot_cpu: Double = 0
if let thread_list = thread_list {
for j in 0 ..< Int(thread_count) {
var thread_info_count = mach_msg_type_number_t(THREAD_INFO_MAX)
var thinfo = [integer_t](repeating: 0, count: Int(thread_info_count))
kr = thread_info(thread_list[j], thread_flavor_t(THREAD_BASIC_INFO),
&thinfo, &thread_info_count)
if kr != KERN_SUCCESS {
return -1
}
let threadBasicInfo = convertThreadInfoToThreadBasicInfo(thinfo)
if threadBasicInfo.flags != TH_FLAGS_IDLE {
tot_cpu += (Double(threadBasicInfo.cpu_usage) / Double(TH_USAGE_SCALE)) * 100.0
}
} // for each thread
}
return tot_cpu
}
fileprivate func convertThreadInfoToThreadBasicInfo(_ threadInfo: [integer_t]) -> thread_basic_info {
var result = thread_basic_info()
result.user_time = time_value_t(seconds: threadInfo[0], microseconds: threadInfo[1])
result.system_time = time_value_t(seconds: threadInfo[2], microseconds: threadInfo[3])
result.cpu_usage = threadInfo[4]
result.policy = threadInfo[5]
result.run_state = threadInfo[6]
result.flags = threadInfo[7]
result.suspend_count = threadInfo[8]
result.sleep_time = threadInfo[9]
return result
}
- Lionking
5
2我有一个问题：我的应用程序的CPU使用率是由我的应用程序计算的还是由iOS计算的？ - Markus
3嗨，马库斯，这个函数返回你的应用程序的 CPU 使用率。 - Lionking
2我认为vm_deallocate是不正确的。在Swift 4中，调用它的正确方式应该是
vm_deallocate(mach_task_self_, vm_address_t(bitPattern: thread_list), vm_size_t(Int(thread_count) * MemoryLayout<thread_t>.stride))。访问thread_list.pointee将返回thread_list的第一个值，而不是数组本身的地址。 - kuwerty谢谢@kuwerty！否则它会不断泄漏。 - RemembranceNN
目前，
var thread_list: thread_act_array_t? = UnsafeMutablePointer(mutating: [thread_act_t]()) 这一行会出现关于悬空指针的警告。我认为应该改成这样：
return thread_list_array.withUnsafeMutableBufferPointer { pointer in
// 其余的代码在这里
}```
@Lionking，请根据这条消息和@kuwerty上面的注释更新答案，以使其与Swift 5.9保持最新。 - undefined0
试试这个：
- (NSString *)cpuUsage
{
kern_return_t kr;
task_info_data_t tinfo;
mach_msg_type_number_t task_info_count;
task_info_count = TASK_INFO_MAX;
kr = task_info(mach_task_self(), TASK_BASIC_INFO, (task_info_t)tinfo, &task_info_count);
if (kr != KERN_SUCCESS)
{
return @"NA";
}
task_basic_info_t basic_info;
thread_array_t thread_list;
mach_msg_type_number_t thread_count;
thread_info_data_t thinfo;
mach_msg_type_number_t thread_info_count;
thread_basic_info_t basic_info_th;
uint32_t stat_thread = 0; // Mach threads
basic_info = (task_basic_info_t)tinfo;
// get threads in the task
kr = task_threads(mach_task_self(), &thread_list, &thread_count);
if (kr != KERN_SUCCESS)
{
return @"NA";
}
if (thread_count > 0)
stat_thread += thread_count;
long tot_idle = 0;
long tot_user = 0;
long tot_kernel = 0;
int j;
for (j = 0; j < thread_count; j++)
{
thread_info_count = THREAD_INFO_MAX;
kr = thread_info(thread_list[j], THREAD_BASIC_INFO,
(thread_info_t)thinfo, &thread_info_count);
if (kr != KERN_SUCCESS)
{
return nil;
}
basic_info_th = (thread_basic_info_t)thinfo;
if (basic_info_th->flags & TH_FLAGS_IDLE)
{
//This is idle
tot_idle = tot_idle + basic_info_th->user_time.microseconds + basic_info_th->system_time.microseconds;
} else {
//This is user
tot_user = tot_user + basic_info_th->user_time.microseconds;
//This is kernel
tot_kernel = tot_kernel + basic_info_th->system_time.microseconds;
}
} // for each thread
kr = vm_deallocate(mach_task_self(), (vm_offset_t)thread_list, thread_count * sizeof(thread_t));
assert(kr == KERN_SUCCESS);
long tot_cpu = tot_idle + tot_user + tot_kernel
return [NSString stringWithFormat:@"Idle: %.2f, User: %.2f, Kernel: %.2f", tot_idle/tot_cpu, tot_user/tot_cpu, tot_kernel/tot_cpu];
}
然而，该方法基于每个进程的起始点计算百分比。如果您正在寻找更传统的计算这些数字的方法，请参见Petesh's answer。
- Coder-256
网页内容由stack overflow 提供, 点击上面的可以查看英文原文，
原文链接
原文链接
task_info()失败的原因，并解决它。请参考这个问题的答案：https://dev59.com/HFTTa4cB1Zd3GeqPwd5g。我认为这是因为你没有初始化port。请使用task_info_self()代替port。 - trojanfoe