I'm not sure if the past few posts are in response to my comment about a crippling COBOL/MVCL problem. If so--and it was not my dog, as Schmuel would say--the offending application had previously worked OK on earlier z hardware. Moving from z10 to z196 was a day-one disaster. Once the smoking MVCL was implicated, the application was improved dramatically with a minor rewrite of just a few lines of source code.
The z196 problem resulted from excessive MVCL execution in the compiled code. MCL was eventually updated in some way to avoid the problem. 'Reasonable' use of MVCL would not have caused a crisis in the first place. The application induced the problem, which did not raise any alarm on earlier hardware. . . JO.Skip Robinson SCE Infrastructure Technology Services Electric Dragon Team Paddler SHARE MVS Program Co-Manager 626-302-7535 Office 323-715-0595 Mobile jo.skip.robin...@sce.com From: "Farley, Peter x23353" <peter.far...@broadridge.com> To: IBM-MAIN@bama.ua.edu Date: 07/15/2011 07:51 AM Subject: Re: Z196 Cobol pgm with higher CPU Sent by: IBM Mainframe Discussion List <IBM-MAIN@bama.ua.edu> May I surmise from the initials MCL that this is a micro- or milli-code fix for a z196 machine? Is it possible that such a fix has implications on lower architecture boxes like z10's? I have no access to IBMLINK or RETAIN or I would look these things up myself. The reason I ask such a question is that in several application-oriented CPU reduction efforts in recent years involving COBOL code, I found that some quite large reductions in average CPU time were gained from the elimination or at least from the minimization of MVCL and CLCL instructions in the generated code. If the z196 has a "speedup" fix for these instructions and if that fix could be back-ported to z10's or even to lower-order boxes, a possibly large amount of COBOL application CPU time could be saved over the z universe... Peter > -----Original Message----- > From: IBM Mainframe Discussion List [mailto:IBM-MAIN@bama.ua.edu] On > Behalf Of Vernooij, CP - SPLXM > Sent: Friday, July 15, 2011 8:45 AM > To: IBM-MAIN@bama.ua.edu > Subject: Re: Z196 Cobol pgm with higher CPU > > I just had it checked and it is MCL 089, available in februari. > RETAIN info: MCL fix U799O089 EC N29799 B28B. > Desc: performance issue seen on customer applications which heavily use > the move char long, move char long extended and move char long Unicode > instructions. ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
