软件测试之性能测试（ios）——获取cpu占用率

ios获取cpu占用率代码如下：

#pragma mark - CPU
- (float)getCpuUsage
{
    kern_return_t           kr;
    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;
    
    //获取当前进程中线程列表
    kr = task_threads(mach_task_self(), &thread_list, &thread_count);
    if (kr != KERN_SUCCESS) {
        return -1;
    }
    float cpu_usage = 0;
    
    for (int i = 0; i < thread_count; i++)
    {
        thread_info_count = THREAD_INFO_MAX;
        //获取每一个线程信息
        kr = thread_info(thread_list[i], 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))
        {
            cpu_usage += basic_info_th->cpu_usage;
        }
    }
    //宏定义TH_USAGE_SCALE返回CPU处理总频率
    cpu_usage = cpu_usage / (float)TH_USAGE_SCALE * 100.0;
    
    //注意方法最后要调用 vm_deallocate，防止出现内存泄漏
    vm_deallocate(mach_task_self(), (vm_offset_t)thread_list, thread_count * sizeof(thread_t));
    return cpu_usage;
}

和instrument里面activity monitor进行对比，数据虽然不能严格匹配上，但是总体的曲线趋势是一样的，如果cpu占用率稳定的情况下，百分比相差不是很大

参考文章

1、https://blog.csdn.net/x1135768777/article/details/11158713
2、http://chuquan.me/2019/06/10/ios-performance-monitor-cpu-mem-fps/
3、https://github.com/aozhimin/iOS-Monitor-Platform#memory