By the way, the execution times even of Listings 1.6 and 1.7 aredominated by DOS disk access times. If a disk cache is enabled and thefile to be checksummed is already in the cache, the assembly version isthree times as fast as the C version. In other words, the inherentnature of this application limits the performance improvement that canbe obtained via assembly. In applications that are more CPU-intensiveand less disk-bound, particularly those applications in which stringinstructions and/or unrolled loops can be used effectively, assemblytends to be considerably faster relative to C than it is in this veryspecific case.