An I/O-Conscious Tiling Strategy for Disk-Resident Data Sets

This paper describes a tiling technique that can be used by application programmers and optimizing compilers to obtain I/O-efficient versions of regular scientific loop nests. Due to the particular characteristics of I/O operations, a straightforward extension of the traditional tiling method to I/O-intensive programs may result in poor I/O performance. Therefore, the technique presented in this paper adapts iteration space tiling for I/O-performing loop nests to deliver high I/O performance. The generated code results in huge savings in the number of I/O calls as well as the volume of data transferred between the disk subsystem and main memory. Our experimental results on the IBM SP-2 distributed-memory message-passing multiprocessor demonstrate that the reduction in these two parameters, namely, the number of I/O calls and the transferred data volume, can lead to a marked decrease in overall execution times of I/O-intensive loop nests. In a number of loop nests extracted from several...

• Type: Journal
• Year: 2002
• Where: TJS
• Authors: Mahmut T. Kandemir, Alok N. Choudhary, J. Ramanujam
• Keywords: Loop Nests, Scientific Loop Nests, TJS 2002, Traditional Tiling Method