IBM Mainframe Discussion List <[email protected]> wrote on 08/06/2008 04:24:17 AM:
> After reading up on <Extended Addressability Guide> ,I am confused on > ASN resue issue. According to the book,if address space owns a spaces > switch ET and connect it to the system lx,then this address space's ASID is > not reusable for the duration of IPL. This is because other address space > could pass control to code running in the address space that reused this > ASID.My question is: > 1. Before service provider(owner of ET) termination, the ET was usually > destroyed(ETDES PURGE=YES), How could the other address space pass > control to PC running in the address space which reused the service > provider's > ASID. How could this happen? Destruction of the ET prevents a subsequent PC from establishing a bind to the ASID. But it does not prevent a workunit which previously issued the PC from being dispatched with that ASID as PASN or SASN. Furthermore, it does not prevent a subsequent PR or PT instruction from establishing a bind to the ASID. > 2. does ASN-reuse-facility have something to do with it,how the ASN- > reuse-facility remedy the potential system integrality problem. > I searched for a couple days but can't find more information,so could you > please explain more details for me. thanks The ASN-reuse-facility introduces the concept of an address space instance number. When the ASID is reused, the instance number is incremented, so that the ASID/Instance Number combination remains unique. Starting with z/OS 1.9, the ASN-reuse-facility can be used to reuse formerly non-reusable ASIDs via the REUSASID=YES parameter on the START command or ATTR=REUSASID on the ASCRE macro. Jim Mulder z/OS System Test IBM Corp. Poughkeepsie, NY ---------------------------------------------------------------------- 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
