On 1/12/2012 7:32 AM, McKown, John wrote:
I ask about the CPU cost of an EX because that same program that I'm working on uses the EX a fair amount to move "variable length" strings into a blank-initialized area for reporting purposes. Instead of EX of an MVC, I could use MVCL or MVCLE. But many have said that EX of an MVC is less overhead than MVCL in many cases. Especially since I know that my length is always no more than 255 characters. I check and report an error if the length is 256 or more.
Relative instruction performance is a moving target. We run benchmarks whenever we get a new processor so we can understand the trends. Most new hardware generations build on the microprocessor design of the prior generation, so the changes tend to be incremental. Now and then, the microprocessor gets completely redesigned. One such redesign occurred with the introduction of the z10. I mentioned our observations re: EXecute and MVCL performance in my "z10 User Experience" at SHARE in Denver. Check out slide 13 for this information. Thanks again to David Bond for helping us make sense of our measurements. http://proceedings.share.org/client_files/SHARE_in_Denver/S2215EJ161728.pdf -- Edward E Jaffe Phoenix Software International, Inc 831 Parkview Drive North El Segundo, CA 90245 310-338-0400 x318 [email protected] http://www.phoenixsoftware.com/
