uint64_t dispatch_benchmark(size_t count, void (^block)(void));
uint64_t n = dispatch_benchmark(10000, ^{
@autoreleasepool {
[self resizeImageByvImage:[UIImage imageNamed:@"a.png"]];
}
});
//类名，方法，行数，用时
NSLog(@"[D] <%@|%@:%d> The average runtime for operation is %llu ns.",
NSStringFromClass([self class]), NSStringFromSelector(_cmd), __LINE__, n);
执行 [self resizeImageByvImage:[UIImage imageNamed:@"a.png"]];方法10000次所用时间
