What are the old and new DCB attributes? -- Shmuel (Seymour J.) Metz http://mason.gmu.edu/~smetz3 עַם יִשְׂרָאֵל חַי נֵ֣צַח יִשְׂרָאֵ֔ל לֹ֥א יְשַׁקֵּ֖ר
________________________________________ From: IBM Mainframe Discussion List <IBM-MAIN@LISTSERV.UA.EDU> on behalf of Robert Prins <000005be6ef5bfea-dmarc-requ...@listserv.ua.edu> Sent: Sunday, January 19, 2025 10:06 AM To: IBM-MAIN@LISTSERV.UA.EDU Subject: Does this make any sense? External Message: Use Caution From LinkedIn: <quote> 2 weeks ago I received the analysis data from a new client that wanted to reduce their CPU consumption and improve their performance. They sent me the statistical data from their z16 10 LPARS. Information about 89,000+ files. I analyzed their data and found 2,000+ files *that could be improved* and would save CPU when improved. *I pulled out 1 file to demonstrate a Proof of Concept (POC) for the client. I had the client run the POC and it showed a 29% reduction in CPU every time that file will be used. The 29% did not include 3 other major adjustments that would save an addition 14% CPU and cut the I/O by 75%.* This is just 1 file. The other files can save 3% to 52% of their CPU every time they are used in BATCH or ONLINE. </quote> I've been a programmer on IBM since 1985, and the above doesn't make any sense to me, how can changing just one file result in a 43% reduction in CPU usage? I've only ever been using PL/I, and using that I did manage to make some improvements to code, including reducing the CPU usage of a CRC routine by an even larger amount, 99.7% (Yes, ninety-nine-point-seven percent), but that was because the old V2.3.0 PL/I Optimizing compiler was absolute shite at handling unaligned bit-strings, but WTH can you change about a file to get the above reduction in CPU? Robert -- Robert AH Prins robert(a)prino(d)org The hitchhiking grandfather <https://secure-web.cisco.com/1ZH7IM5vfOREKZ3rQyTITbDCH1Kxxv42P7MGdczzN_5ek7CVPV_qQFOYwqmHwKUWarkfV8ubc_KQCg2bQ0x9YLMztnl9dU_WQvWsRznr7clwsFHj0hRSD-U8uO2JtKWQbbtxFhQvJn-rqNTdv6pf2dndHuH6VwAvro-mn2Gk-Cfh2OwAKsiYEA4vDnySd518CrPpow-QBr5A9prHo4dljieHuXi06FO5ufAUh5-xGnR7JkwAzQZPw3MftJVkfwHJh-yB_Zi2zm2lg2IEIFd4ukHzkzOfM5qmF4gF0cfh5jwFCA6uG63UOZHLbahW5F6CHL0jYfg_-UTvhIetQTNGt_iMSvGjUBNxlWMZWIWIhg_c9RV-urPyqNz6TEzwPZUq_D_E2OU37xvHjY_j9dJvkpTxwcGGNFrCxmas9YQFkrBHxr7ETTZm1hn2MmaQa09u1/https%3A%2F%2Fprino.neocities.org%2Findex.html> Some REXX code for use on z/OS <https://secure-web.cisco.com/1fRhf72BBOA0cYAcxoMDVLuIargyJSFK1QC2PTbjJweApdb-A2pQJKr3_gFQaJYSzpOwO-LA8EXfGlJd9Rw_DWNdG45cnL-LA1pIiFJC_MyiObbNkHN-ew5GeeICG1jAzr8FPuyvpZpx7ICsBJa0WRjMDOs58IlB39X-UrsWYutveBWus0uphX_xb4t10WNLvjuegaQZ1aK9zuLPLxwM7aYxRVJiqa8YNOSShqvCIeSjg9g5s9bg7uwMVYHY8eHjs2BHHBSImPtUjLwM3sUdLJgJH7wuOsIJLhQKG7N2AM0MU9Ys9xMKJrbEKhFjBerwSS11Fh2qCROvRKu1yEiPE0OImuDN4ovB7VZg84nLsQ6F0nbmSjeC5rsQabK6ZqR4XDT2lfngNAv2PxQoTB-15BTz1lao0LGTCSARfbSb38TtkrcMTSnXqjUyFdvEX4p9O/https%3A%2F%2Fprino.neocities.org%2FzOS%2FzOS-Tools.html> ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
