Larry, Depends on the OS and SMS versus non-SMS. Extended PS is the same as VSAM (123 extents/vol) and max of 59 vols, for total of 7,257. Prior to z/OS 1.7, the VSAM extent limit was 255 total. There is a dataclass option to enforce this 255 limit if users share the VSAM dataset with older releases of z/OS. The VSAM limit of 255 extents is still enforced for any non-SMS-managed data set. The system reserves the last four extents for extending a component when the system cannot allocate the last extent in one piece. Non-SMS datasets still play by the old rules.
Michael Spencer BMC Software -----Original Message----- From: IBM Mainframe Discussion List [mailto:[email protected]] On Behalf Of larry macioce Sent: Wednesday, April 08, 2009 10:04 AM To: [email protected] Subject: Secondary space allocation I was doing some reading,which is scary in it's own right, and came across something that I need to verify.I always thought when you gave a secondary space allocation that it went to 16 extents(if needed), but I am reading that it now goes to 123. Is this true?? We are a non sms shop. One more question, does the system check for all secondary allocations or will it work 1 by 1 as needed? thanks Larry ---------------------------------------------------------------------- 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
