The coordination with other CPUs is in getting exclusive control of the storage operand cache line. CS and ST both have to do that, so they would be similar in performance in that regard.
Jim Mulder z/OS Diagnosis, Design, Development, Test IBM Corp. Poughkeepsie NY > From: "Charles Mills" <charl...@mcn.org> > To: ASSEMBLER-LIST@LISTSERV.UGA.EDU > Date: 01/10/2019 01:04 AM > Subject: Re: Multi CPU interlock question > Sent by: "IBM Mainframe Assembler List" <ASSEMBLER-LIST@LISTSERV.UGA.EDU> > Avoid CS if you don't need it (and in this case you don't). CS is > expensive because every CPU has to sit up and take notice.
