I would think that JES is something of a special case. It does I/O for a living and I would imagine it has gotten pretty good at it over the decades.
For example, I don't really know, but it might be reasonable for JES to manage device queuing internally and therefore not be visible to ordinary measuring tools. Just a thought. -----Original Message----- From: IBM Mainframe Discussion List [mailto:[EMAIL PROTECTED] On Behalf Of Van Dalsen, Herbie Sent: Wednesday, January 09, 2008 7:18 AM To: [email protected] Subject: Re: Allocating Large SYS1.HASPACE Ulrich, I don't have a spare array to test this on, but how much do you loose in creating PAV's in terms of usable space on the shark / performance / internal memory usage in the shark... Is 64 3390-3's such a bad thing considering the bottleneck on the control block? Regards Herbie -----Original Message----- From: IBM Mainframe Discussion List [mailto:[EMAIL PROTECTED] On Behalf Of Ulrich Krueger Sent: 03 Desember 2007 03:48 nm To: [email protected] Subject: Re: Allocating Large SYS1.HASPACE > I'm going to give the 3390-27 a try, on at least on my largest system. I'm hoping to replace 64 3390-3s. If you do go to -27 disks, please make sure that the DASD string(s) for your new SPOOL volumes are defined with enough PAV aliases available so that you don't get I/O performance issues. Regards, Ulrich Krueger -----Original Message----- From: IBM Mainframe Discussion List [mailto:[EMAIL PROTECTED] On Behalf Of Dennis Schaffer Sent: Sunday, December 02, 2007 23:10 To: [email protected] Subject: Re: Allocating Large SYS1.HASPACE Claude, Thanks. DSNTYPE=LARGE is exactly what I needed. Skip and Sam, thanks for your input, too. I'm going to give the 3390-27 a try, on at least on my largest system. I'm hoping to replace 64 3390-3s. Thanks, Dennis NOTICE: This electronic mail message and any files transmitted with it are intended exclusively for the individual or entity to which it is addressed. The message, together with any attachment, may contain confidential and/or privileged information. Any unauthorized review, use, printing, saving, copying, disclosure or distribution is strictly prohibited. If you have received this message in error, please immediately advise the sender by reply email and delete all copies. ---------------------------------------------------------------------- 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
