-----Original Message----- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@LISTSERV.UA.EDU] On Behalf Of Mike Schwab Sent: Monday, March 04, 2013 23:59 To: IBM-MAIN@LISTSERV.UA.EDU Subject: Re: Paging Behaviour; was: Re: DFSORT Weirdness
When we have done PAGEADD and PAGEDELs for Volume migrations to new UCBs, what it does is balance by I/O. While the PAGEDELS are going, as soon as one write is completed, the next write starts, pretty much round robin. In your case I would hypethosis it tries the first page dataset on a volume and only uses the second if the first one is still busy. This is not how it works. ASM uses the page datasets in round-robin. They are on a circular queue, as it was explained to me. If they are all the same size, they are all filled for about the same percentage. So you can determine what surprises (and therefor overhead) you confront ASM with when they have different sizes. In the old PAV situation, ASM ensured 2 access paths (real or alias) to each page dataset, so it would not cause contention with itself. Now this has been abandoned because Hiperpav ensures the access paths. 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 lists...@listserv.ua.edu with the message: INFO IBM-MAIN
