"Murray M. Robinson" <[EMAIL PROTECTED]> wrote in message news:<[EMAIL PROTECTED] om>... > I am finding hard to persuade some old time IBM developers that planning > to disperse dataset allocation as if they were accessing old discreet 3390 > disks is a futile effort. Ignoring that with PAV and WLM goal mode and > 3390s only logical and no one really knows were all the pieces are stored > on the much fewer physical disks emulating thousands of volumes. I suggest > use SMS without requesting Guaranteed space and placing their datasets on > specific volumes is not getting through to them. Please help direct me to > some decent documentation explaining this. Also if anyone knows when this > technique is still relevant I'd love to know. Also which RMF screen gives > a good snapshot of IO activity (and caching) > Thanks. >
I am not familiar with the ds6000/8000 and their internal structure, but with the ESS we definitely had a need to spread datasets. As long as you do I/O to and from cache, the place of the data is not relevant. But as soon as you must read from the backend (internal disks) you are back again to I/O to real disks and their internal paths, limitations and contention, similar to the old 3390's. E.g. we had a lot of problems with DB2 log archiving that could only be solved by spreading logging volumes over many internal loops and raidstructures to prevent contention as much as possible. Kees. ********************************************************************** For information, services and offers, please visit our web site: http://www.klm.com. This e-mail and any attachment may contain confidential and privileged material intended for the addressee only. If you are not the addressee, you are notified that no part of the e-mail or any attachment may be disclosed, copied or distributed, and that any other action related to this e-mail or attachment is strictly prohibited, and may be unlawful. If you have received this e-mail by error, please notify the sender immediately by return e-mail, and delete this message. Koninklijke Luchtvaart Maatschappij NV (KLM), its subsidiaries and/or its employees shall not be liable for the incorrect or incomplete transmission of this e-mail or any attachments, nor responsible for any delay in receipt. Koninklijke Luchtvaart Maatschappij N.V. (also known as KLM Royal Dutch Airlines) is registered in Amstelveen, The Netherlands, with registered number 33014286 ********************************************************************** ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
