In a recent note, Robert Wright said: > Date: Tue, 17 Jan 2006 11:23:34 -0500 > > Brian Peterson wrote on 01/17/2006 10:48:40 AM: > > > The two concepts - 1) marking an allocation "not in use" and reusing a > "not > > in use" allocation, and 2) using the REUSE keyword on the ALLOC command, > > are two totally separate and distinct concepts. > > Total separation is a slight overstatement. The in-use bit may interact > with an attempt to free a ddname so a replacement can be established. It > would be reasonable for DYNALLOC to reject a request to free an in-use > ddname unless the requester explicitly said it was OK. > Thanks to both of you.
So, then, what is TSO ALLOCATE's rationale for making REUSE and PATH mutually exclusive? > Yes, it can by-pass catalog lookup if the requestor uses a combination of > DYNALLOC keys implying acceptance of ddname reuse. You'll find a list of > keys that prevent such ddname reuse as part of DYNALLOC documentation. The > performance gain can result from less ENQs ranging from ones that are > sysplex-wide (e.g. system catalog requests) to ones for the TIOT. The > SYSDSN ENQ is in effect as long as the dsname is allocated and reflects the > Does this mean even while allocated, but marked not-in-use? > highest level of serialization ever needed while one or more ddnames were > associated with the dsname. Thanks again, gil -- StorageTek INFORMATION made POWERFUL ---------------------------------------------------------------------- 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
