The expected benefit of all performance options is invariably "it depends". All you need to know is the characteristics of the I/O workload the mod-27's will be supporting and you'll know how to respond to the IBM peddler's attempt to peddle FUD (fear, uncertainty, doubt).
If the mod-27 is going to contain a single very large dataset with relatively few simultaneously open DCBs/ACBs (favorite example: SMPPTS) or will contain a whole bunch of datasets whose I/O service time won't matter to production SLAs (example: the DLIB collection), then IOSQ time will be minimal (in the first case) and won't matter (in the second case). If the mod-27 is going to contain DB2 work tablespaces that are heavily used by online activities, IOSQ time might be problematic - or might not. Tom Puddicombe Mainframe Performance & Capacity Planning CSC 71 Deerfield Rd, Meriden, CT 06450 ITIS | (860) 428-3252 | [EMAIL PROTECTED] | www.csc.com This is a PRIVATE message. If you are not the intended recipient, please delete without copying and kindly advise us by e-mail of the mistake in delivery. NOTE: Regardless of content, this e-mail shall not operate to bind CSC to any order or other contract unless pursuant to explicit written agreement or government initiative expressly permitting the use of e-mail for such purpose. james smith <[EMAIL PROTECTED]> Sent by: IBM Mainframe Discussion List <[email protected]> 11/04/2008 06:43 AM Please respond to IBM Mainframe Discussion List <[email protected]> To [email protected] cc Subject Performance Question - Dynamic PAV we have a customer panicking because an IBM presenter 'suggested' that you should not use Mod-27 devices for critical data UNLESS you have hyper PAV installed as you are likely to see problems with IOSQ times. Not sure about the validity of the comments so I thought I would seek out opinions on the list. He may just have been plugging the DS8000 box which comes with hyper PAV....... after all it was a 'dog and pony' show. Jim S. ---------------------------------------------------------------------- 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 ---------------------------------------------------------------------- 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
