iphone memory usage

.m

#import mach/mach.h

void report_memory(void) {
struct task_basic_info info;
mach_msg_type_number_t size = sizeof(info);
kern_return_t kerr = task_info(mach_task_self(),
                               TASK_BASIC_INFO,
                               (task_info_t)&info,
                               &size);
if( kerr == KERN_SUCCESS ) {
  NSLog(@"Memory used: %u", info.resident_size); //in bytes
} else {
  NSLog(@"Error: %s", mach_error_string(kerr));
}
}