Sorting is an important operation of transaction processing. It is a relatively mature field, as many algorithms for memory sorting, disk sorting and parallel sorting have come forth in the past decades. In this paper, the sorting algorithm is studied from a thoroughly different standpoint, and the THSORT (Tsinghua SORT), a parallel sorting algorithm on a single computer, is brought forward. THSORT uses several processes to control different components of a computer, which enables the data input, sorting and output to be run concurrently, and thus greatly enhances the parallelism and efficiency of the hardware. Experimental results based on a computer with two RAIDs (redundant array of inexpensive disks) indicate that THSORT has almost doubled the performance of NTSORT (new technology SORT), a famous sorting program. Moreover, THSORT has won the 2002 PennySort competition and is still holding the world record in the Daytona category.