獲取iOS中GPU所使用的內存

Question

如何獲取iOS中GPU（視頻）所使用的RAM內存？

我能夠得到以下的內存數據：active_count，inactive_count，wire_count，free_count，而不是視頻使用的內存。

Answer 1

這一切首先是我使用來獲得內存使用方法：

#import <mach/mach_host.h> 

NSDictionary* getMemoryState(){ 

    mach_port_t host_port; 
    mach_msg_type_number_t host_size; 
    vm_size_t pagesize; 

    host_port = mach_host_self(); 
    host_size = sizeof(vm_statistics_data_t)/sizeof(integer_t); 
    host_page_size(host_port, &pagesize); 

    vm_statistics_data_t vm_stat; 

    if (host_statistics(host_port, HOST_VM_INFO, (host_info_t)&vm_stat, &host_size) != KERN_SUCCESS) { 
     NSLog(@"Failed to fetch vm statistics"); 
    } 

    /* Stats in bytes */ 
    natural_t mem_used = (vm_stat.active_count + 
          vm_stat.inactive_count + 
          vm_stat.wire_count) * (unsigned int) pagesize; 

    natural_t mem_free = vm_stat.free_count * (unsigned int)pagesize; 
    natural_t mem_total = mem_used + mem_free; 

    //NSLog(@"used: %u free: %u total: %u active: %u video: %u", mem_used/1024 /1024, mem_free/1024 /1024, mem_total/1024 /1024, vm_stat.active_count, 999 - (mem_total/1024 /1024)); 

    NSMutableDictionary *dictWithMemoryStats = [[NSMutableDictionary alloc] initWithObjectsAndKeys: 
               [NSNumber numberWithInt:mem_total/1024/1024] , @"total", 
               [NSNumber numberWithInt:mem_used/1024/1024], @"used", 
               [NSNumber numberWithInt:mem_free/1024/1024], @"free", 
               [NSNumber numberWithInt:((vm_stat.active_count * (unsigned int) pagesize)/1024/1024)], @"active", 
               [NSNumber numberWithInt:(vm_stat.inactive_count * (unsigned int) pagesize)/1024 /1014], @"inactive", 
               [NSNumber numberWithInt:(vm_stat.wire_count * (unsigned int) pagesize)/1024/ 1024], @"wire", 
               nil]; 

    return dictWithMemoryStats; 

} 

然後，爲了獲得通過，必須得到設備的總RAM內存，從中減去GPU佔用的內存從上述方法獲得的總內存。

let dictWithRamInfi: NSDictionary = getMemoryState() 
let proInfo = NSProcessInfo.processInfo() 

let totalRam: UInt64 = ((proInfo.physicalMemory/1024)/1024) 
let totalActiveRam: UInt64 = UInt64(dictWithRamInfi["total"]!.unsignedLongLongValue) 

let videoRam = totalRam - totalActiveRam