App运行内存打印

移动设备内存较小，开发期间，很容易导致设备出现内存警告，这个时候打印出内存信息可以帮助我们了解内存情况

1，可用内存

float AppDelegate::availableMemory()

{

    mach_msg_type_number_t infoCount = HOST_VM_INFO_COUNT;

    vm_statistics_data_t vmStats;

    kern_return_t kernReturn = host_statistics(mach_host_self(), HOST_VM_INFO, (host_info_t)&vmStats,

                                                   &infoCount);

    if(kernReturn != KERN_SUCCESS)

    {

        return 0;

    }

    return ((vm_page_size * vmStats.free_count) / 1024.0) / 1024.0;

}

 

2. app占用内存，可以在内存警告发生时打印该数据

float AppDelegate::usedMemory()

{

    task_basic_info_data_t taskInfo;

    mach_msg_type_number_t infoCount = TASK_BASIC_INFO_COUNT;

    kern_return_t kernReturn = task_info(mach_task_self(), TASK_BASIC_INFO, (task_info_t)&taskInfo, &infoCount);

    if (kernReturn != KERN_SUCCESS) {

        return 0;        

    }

    return taskInfo.resident_size / 1024.0 / 1024.0;

}