On Tue, Mar 31, 2009 at 5:18 PM, Steve Wilkins <[email protected]> wrote:
> Usually the parts in a single Diag x250 request are reordered and kept in as > few channel programs as possible. However, if alias devices are attached to > the system, these channel programs will be issued to the first available > base or alias device (for minidisk I/O). And when the disks fit the proper criteria, MDC could also be in the play. When the I/O is partially satisfied from MDC, we may need two separate real I/O's to deal with the remainder. With the small mini disks and small I/O's that Gary suggested, I suppose track-based MDC might do a nice job avoiding some of the read I/O's completely. Rob -- Rob van der Heij Velocity Software http://www.velocitysoftware.com/
