Creating dbspaces on multiple files

Due to the IBM implementation of reads for JFS database files, Sybase IQ performance improves if you create dbspaces on each disk instead of one large file. Creating smaller files allows Sybase IQ to handle disk I/O operations much more efficiently, especially when combined with disk striping and possibly multiple controllers.

Currently Sybase recommends creating three files per underlying disk drive.

When setting up raw partitions, the system administrator specifies the sector size, which defines the minimum usable chunk of disk (and, hence, the minimum Sybase IQ block size). You must specify a block size for Sybase IQ that is an integer multiple of the sector size when you use raw partitions. The Sybase IQ System Administration Guide provides details on specifying block size.