For performance-critical applications, the overhead of the Journaled File System (JFS) for I/O operations might slow down the program. If your program generates large scratch files, you might find that I/O bandwidth also limits its performance. Performing I/O directly to a logical volume rather than to a file system can eliminate the JFS overhead. Using data striping on the logical volume can further improve throughput or processor utilization or both.
Because data-striped I/O runs much faster for data items that are aligned more strictly than normal, ensure that variables involved in logical volume I/O or data striping are properly aligned. You can do this by using the -qalign option or the ALIGN directive.