>PLO CDS does exactly what is wanted. I presume this was a typo and should have been PLO DCS (double compare and swap)
PLO CSDST (and CSST and CSTST) have limitless potential exploitations. It all depends on what your requirements are. Suppose you have N (>2) separate fields all of which need to be serialized together and the happy circumstance is that you never need to update more than 2 of them together. A counter (subject of the CS) and store(s) may be used to do the updates. >Since 3 separate load instructions I wonder if a double compare and swap can guarantee the consistency of 3 load instructions. To the extent that a "free queue" protocol is analogous, you have to use a sequence number to get that right. >(not under PLO control) Why is that a requirement? It is far from unheard of to use PLO Compare-and-load Peter Relson z/OS Core Technology Design ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
