> >With disablement, you can guarantee that your processor will not be > >interrupted between fetching the address and accessing it > > You can not, however, be guarntied that another processor won't change > anything. What happens if z/OS is in the middle of taking the other > CPU offline?
CPU Offline processing turns off the CSD alive bit, and zeros the PCCAVT and LCCAVT entries for the CPU that is going offline. Then a Bind Break is done, and this does not complete until every other CPU has enabled at least once. After that, the LCCA, PCCA, and PSA can be freed. So if you disable, and then fetch a non-zero address for a PCCA from the PCCAVT or LCCA from the LCCAVT, the PCCA, LCCA, and associated PSA will not be freed as long as you remain disabled. 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: INFO IBM-MAIN
