Right ... the point being "don't bother figuring out whether store or store halfword is faster -- change your algorithm so you have only 1/1000 as many stores."
Charles -----Original Message----- From: IBM Mainframe Discussion List [mailto:[email protected]] On Behalf Of Tom Brennan Sent: Thursday, December 24, 2015 1:52 PM To: [email protected] Subject: Re: Is there a source for detailed, instruction-level performance info? Farley, Peter x23353 wrote: > So what is an ordinary programmer to do? Years ago I guess I had nothing to do so I wrote a program that hooked into various LINK/LOAD SVC's and recorded the load module name (like Isogon and TADz do). That huge pile of data ended up on a tape and I wrote some code to scan the tape for a particular module, to find out who was using it and how often. The scan took forever, so I worked quite a bit trying to make the main loop more efficient. Co-worker Stuart Holland looked at my logic and quickly switched it to using a hashing lookup algorithm, making it run probably a thousand times faster. Oops :) ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
