And keep in mind that they use different locking mechanisms. If routine A uses CS and routine B uses PLO to protect a given field, then they will not lock each other out and you will potentially have collision problems.
Charles -----Original Message----- From: IBM Mainframe Assembler List [mailto:[email protected]] On Behalf Of Jim Mulder Sent: Sunday, August 13, 2017 11:36 PM To: [email protected] Subject: Re: Just Testing - It got very quiet PLO and CS have very different performance characteristics. CS is a hardware instruction which which performs the serialization by maintaining exclusive access to the cache line containing the operand. PLO is like a software disabled spin lock, but implemented in millicode. Millicode obtains the spin lock, performs the requested operation, and releases the lock. Jim Mulder z/OS Diagnosis, Design, Development, Test IBM Corp. Poughkeepsie NY > PLO is CS on steroids. I can give you specific examples just let me > know what you are looking to do. PLO works well with linked list > node inserts and deletes. It does take a number of instructions of > prep work to fill the PLO parameter block if you are using the > triple store operation.
