Calculating free memory on an iPhone

[PISD Support]

To calculate the amount of memory left free on the iPhone use this handy code snippet*:

Code: Select all

static void print_free_memory( void ) 
{
    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) * pagesize;
    natural_t mem_free = vm_stat.free_count * pagesize;
    natural_t mem_total = mem_used + mem_free;
    NSLog(@"used: %u free: %u total: %u", mem_used, mem_free, mem_total);

} // print_free_memory()

*Taken from http://www.gauravv.com/2009/11/27/iphon ... ee-memory/