I recommend you speak to Martin Packer at IBM. Lennie -----Original Message----- From: IBM Mainframe Discussion List <IBM-MAIN@LISTSERV.UA.EDU> On Behalf Of Colin Paice Sent: 01 March 2023 18:00 To: IBM-MAIN@LISTSERV.UA.EDU Subject: Hardware instrumentation presentation
I've been asked to give a talk on performance to a University Computing department. I know the z hardware has in builtin instrumentation which allows you to see where the delays were for a particular instruction. For example this load instruction got data from the L3 cache and it took x nano seconds. Is there a presentation on this? I remember seeing a presentation (it may have been IBM confidential) showing that a Load could be slow, if the data was in a the cache in a book 3 ft away, compared to it being in the cache on the chip. Also the second time round a loop is faster than the first time because the instructions are in the instruction cache. This was all mind blowing stuff! Colin ---------------------------------------------------------------------- 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
