Argonne National Laboratory

Noncontiguous I/O through PVFS

TitleNoncontiguous I/O through PVFS
Publication TypeReport
Year of Publication2002
AuthorsChing, A, Choudhary, A, Liao, W-K, Ross, RB, Gropp, WD
Date Published07/2002
Other NumbersANL/MCS-P970-0702

With the tremendous advances in processor and memory technology, I/O has risen to become the bottleneck in high-performance computing for many applications. The development of parallel file systems has helped to ease the performance gap, but I/O still remains an area needing significant performance improvement. Research has found that noncontiguous I/O access patterns in scientific applications combined with current file system methods to perform these accesses lead to unacceptable performance for large data sets. To enhance performance of noncontiguous I/O, we have created list I/O, a native version of noncontiguous I/O. We have used the Parallel Virtual File System (PVFS) to implement our ideas. Our research and experimentation shows that list I/O outperforms current noncontiguous I/O access methods in most I/O situations and can substantially enhance the performance of real-world scientific applications.