Re: Kinda fun
Bob Bridges wrote on 11/8/2023 7:00 AM: Let's see, how many nanoseconds is that again? The answer to that is as relevant today as it was 50 years ago with Bus and Tag cables: The speed of light is very close to 1 foot per nanosecond. So making computer chips smaller and smaller inherently increases the speed. How much delay is that for a channel extender (whatever the tech is today) for your remote copy dasd that's many miles away across town? /Leonard -Original Message- From: IBM Mainframe Discussion List On Behalf Of Allan Staller In those days, the limit on bus/tag cables was 200 ft (cumulative). IIRC, that particular block multiplexer was running about 190 ft. De-installing the 2503 saved about 125 ft. -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: Kinda fun
Bob Bridges wrote on 11/8/2023 6:56 AM: Reminds me of an old tagline: /* The more sophisticated the technology, the more vulnerable it is to primitive attack. People often overlook the obvious. -Dr Who, 1978 */ Long ago I was told why my shop didn't carpet the tape storage area. Apparently some shop that did had a problem with unreadable tapes. Eventually they figured out that all the unreadable tapes were on the bottom row of the tape storage. And the outside cleaning people used a vacuum cleaner... Farley, Peter wrote on 11/8/2023 7:58 AM: 1401N1 printer (the big beast) raised its hood automatically when it ran out of paper, no way to turn off that behavior. NEVER put your coffee cup on top of that printer!! Supposedly the reason that IBM put that feature on the 1403 was some big shops had a lot of 1403s and it helped the operator find the printer that needed to be fed. Unfortunately, the feature didn't have a failsafe. It was common to stack boxes of paper behind the printer. At least once at UCLA, someone had stacked it one box too high, and when the printer cover went up, the back end of the cover was blocked by the too-high stack, raising the printer off the floor. And BTW, the 3211 had a "raise cover" CCW. I had some fun with that, and one of the other IBM-MAIN readers probably remembers that, from Post 360. On Wed, 8 Nov 2023 09:49:34 -0500, Rick Troth wrote: I've heard tales (probably at KTRU) of reading magnetic tape/cards with iron filings and a loupe. In high school, I watched a guy splice 1" reel-to-reel video tape and avoid the picture rolling by finding the sync marks with the above method and carefully cutting the tape right on the sync marks. BTW, I still have around 12 or so boxes of 2000 blank 80 column cards. That's about 500 years of shopping lists... /Leonard -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: LA vs LHI
The difference, if any, should be in the cache loading. In practice. if I have to set up multiple base registers then I would wrap everything in a macro, using LAY if there were only two base registers. For 3 or more I'd use LHI to load the last with 4096 and use LA for the second through last. Of course, 2048 works just as well. -- Shmuel (Seymour J.) Metz http://mason.gmu.edu/~smetz3 עַם יִשְׂרָאֵל חַי From: IBM Mainframe Discussion List on behalf of Tony Harminc Sent: Friday, November 10, 2023 3:17 PM To: IBM-MAIN@LISTSERV.UA.EDU Subject: Re: LA vs LHI On Fri, 10 Nov 2023 at 08:27, Seymour J Metz wrote: > I know that it's model dependent and also depends on the cache loading, > but are there cases where there is a measurable performance difference > between these? > > LAY Rx,4096 > LHI Rx,4096 > It seems highly implausible to me that there'd be any difference. Surely the LAY case of base and index register = 0 are special cased, and there need be no waiting for the actual value of R0 to settle. A case I find a bit more interesting is setting up the typical second base register. LAY Rx,4096(,Ry) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: Subject: Re: Kinda fun
Diagonal line, I never thought of that! But I only just now realized why a dropped deck was never much of an issue for me. (I'm slow.) I was, as I said, a $HASP operator - but a) the social-scientist geeks who brought in large boxes of cards didn't care about the order, and anyway I never happened to drop a box. And b) whatever I wrote myself was as a student, and student assignments just don't get that long - 50 cards at most, unlike the stuff I write professionally. I'm just not old enough to have used cards on the post-college jobs. --- Bob Bridges, robhbrid...@gmail.com, cell 336 382-7313 /* Wear your learning, like your watch, in a private pocket, and do not pull it out and strike it merely to show you have one. If you are asked what o'clock it is, tell it, but do not proclaim it hourly and unasked, like the watchman. -Lord Chesterfield */ -Original Message- From: IBM Mainframe Discussion List On Behalf Of billogden Sent: Friday, November 10, 2023 16:51 I used 026, 029, and 129 machines. (And the 010 machines; remember those!) Never bothered me, but I agree with the comment that their use (and punched cards in general) encouraged me to be much more careful with my "on paper" programming before starting to punch cards. Dunno how to translate this "feeling" into the modern world where we start typing (on a graphics screen) before we have finished deciding how the program "should" work. Times certainly change. Also as mentioned, I quickly found it was better to do my own keypunching! I had lots of "hands on" on 1620s, 1401s, 1410s, and 7040s. (I used 7090s and 7094s, but not "hands on"!) Being ancient and over the hill, I cannot remember how I worked with our 1130s and 1800s (and 1500s, if you remember those). I remember paper tape on one of the 1620s and I hated it! Trying to make modern sense of this discussion (if possible) I can see where starting to type before most of the thinking process is complete can lead to a "liking" for interpreted languages --- where at least some of the error messages occur at the typing stage --- instead of much later times that occur long after the keypunching stage! In a sense, it often seems that some of our "modern" techniques have eliminated inspecting compiler listings. ... Why sequence numbers? Like many of us, I used a carefully drawn diagonal line (with a "magic marker") across the top of the card deck as a useful restoration tool when I dropped the deck! -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: Subject: Re: Kinda fun
When I was at IBM, circa 1964, we had a keypunch department because ran other businesses' work. The keypunch ladies were infinitely faster, did the verification step and always added the sequence numbers so any oddities were generally on you. John T. Abell Tel:800-295-7608Option 4 President International: 1-416-593-5578 Option 4 E-mail: john.ab...@intnlsoftwareproducts.com Fax:800-295-7609 International: 1-416-593-5579 International Software Products www.ispinfo.com This email may contain confidential and privileged material for the sole use of the intended recipient(s). Any review, use, retention, distribution or disclosure by others is strictly prohibited. If you are not the intended recipient (or authorized to receive on behalf of the named recipient), please contact the sender by reply email and delete all copies of this message. Also,email is susceptible to data corruption, interception, tampering, unauthorized amendment and viruses. We only send and receive emails on the basis that we are not liable for any such corruption, interception, tampering, amendment or viruses or any consequence thereof. -Original Message- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@LISTSERV.UA.EDU] On Behalf Of billogden Sent: Friday, November 10, 2023 4:51 PM To: IBM-MAIN@LISTSERV.UA.EDU Subject: Subject: Re: Kinda fun I used 026, 029, and 129 machines. (And the 010 machines; remember those!) Never bothered me, but I agree with the comment that their use (and punched cards in general) encouraged me to be much more careful with my "on paper" programming before starting to punch cards. Dunno how to translate this "feeling" into the modern world where we start typing (on a graphics screen) before we have finished deciding how the program "should" work. Times certainly change. Also as mentioned, I quickly found it was better to do my own keypunching! I had lots of "hands on" on 1620s, 1401s, 1410s, and 7040s. (I used 7090s and 7094s, but not "hands on"!) Being ancient and over the hill, I cannot remember how I worked with our 1130s and 1800s (and 1500s, if you remember those). I remember paper tape on one of the 1620s and I hated it! Trying to make modern sense of this discussion (if possible) I can see where starting to type before most of the thinking process is complete can lead to a "liking" for interpreted languages --- where at least some of the error messages occur at the typing stage --- instead of much later times that occur long after the keypunching stage! In a sense, it often seems that some of our "modern" techniques have eliminated inspecting compiler listings. ... Why sequence numbers? Like many of us, I used a carefully drawn diagonal line (with a "magic marker") across the top of the card deck as a useful restoration tool when I dropped the deck! Bill Ogden -- 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
Subject: Re: Kinda fun
I used 026, 029, and 129 machines. (And the 010 machines; remember those!) Never bothered me, but I agree with the comment that their use (and punched cards in general) encouraged me to be much more careful with my "on paper" programming before starting to punch cards. Dunno how to translate this "feeling" into the modern world where we start typing (on a graphics screen) before we have finished deciding how the program "should" work. Times certainly change. Also as mentioned, I quickly found it was better to do my own keypunching! I had lots of "hands on" on 1620s, 1401s, 1410s, and 7040s. (I used 7090s and 7094s, but not "hands on"!) Being ancient and over the hill, I cannot remember how I worked with our 1130s and 1800s (and 1500s, if you remember those). I remember paper tape on one of the 1620s and I hated it! Trying to make modern sense of this discussion (if possible) I can see where starting to type before most of the thinking process is complete can lead to a "liking" for interpreted languages --- where at least some of the error messages occur at the typing stage --- instead of much later times that occur long after the keypunching stage! In a sense, it often seems that some of our "modern" techniques have eliminated inspecting compiler listings. ... Why sequence numbers? Like many of us, I used a carefully drawn diagonal line (with a "magic marker") across the top of the card deck as a useful restoration tool when I dropped the deck! Bill Ogden -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: LA vs LHI
On Fri, 10 Nov 2023 at 08:27, Seymour J Metz wrote: > I know that it's model dependent and also depends on the cache loading, > but are there cases where there is a measurable performance difference > between these? > > LAY Rx,4096 > LHI Rx,4096 > It seems highly implausible to me that there'd be any difference. Surely the LAY case of base and index register = 0 are special cased, and there need be no waiting for the actual value of R0 to settle. A case I find a bit more interesting is setting up the typical second base register. LAY Rx,4096(,Ry) vs LRRx,Ry AHI Rx,4096 or the pre-LAY sequence LA Rx,4095(,Ry) LA Rx,1(,Rx) (or occasionally 2048 in both - symmetry?) both of which are surely slower than either of the single-instruction approaches. Stylistically in any case I prefer the LAY over LHI/AHI, because it somehow emphasizes to me the notion of incrementing one register by 4096 over the other. In your original case, and assuming there's no performance difference, I'd choose based on what Rx is going to used for. If it's going to be part of stepping through addresses (setting up for a BXLE or the like), then I'd use LAY. Otherwise LHI. Tony H. -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: LA vs LHI
I suspect that the extra halfword has more impact on performance than the register, and I agree that the performance difference is probably negligible. Just curious. -- Shmuel (Seymour J.) Metz http://mason.gmu.edu/~smetz3 עַם יִשְׂרָאֵל חַי From: IBM Mainframe Discussion List on behalf of Adam Johanson <031ca9d720a7-dmarc-requ...@listserv.ua.edu> Sent: Friday, November 10, 2023 12:26 PM To: IBM-MAIN@LISTSERV.UA.EDU Subject: Re: LA vs LHI >I know that it's model dependent and also depends on the cache loading, but >are there cases where there is a measurable performance difference between >these? > > LAY Rx,4096 > LHI Rx,4096 One aspect of the differences between the two is that LAY has a larger footprint in the i-cache since it's a 6-byte instruction vs. the 4-byte LHI. Finding / constructing a use case where that makes a measurable performance difference could be an interesting exercise. === Adam Johanson Broadcom Mainframe Software Division -- 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
Re: Kinda fun
On Fri, 10 Nov 2023 13:02:29 -0500, Tony Harminc wrote: >On Thu, 9 Nov 2023 at 17:48, Paul Gilmartin < >042bfe9c879d-dmarc-requ...@listserv.ua.edu> wrote: >> > >> I believe I saw one. A flat container of ferrite slurry with a >> transparent top >> and a diamagnetic membrane bottom. Pressed against the tape, it clearly >> showed record gaps. Reading the data would have been a challenge, >> even at lowest density. > >I have a can of that iron-filings-in-solvent from around 40 years ago. I >havent played with it for a few years, but the solvent hadn't evaporated, >and it still worked. > >It is indeed not feasible to read 1/2" mag tape even at 800 BPI, but what I >was able to read with just a magnifying glass is the magstripe on old >pre-chip credit cards. > What about low density? -- gil -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: Kinda fun
On Thu, 9 Nov 2023 at 17:48, Paul Gilmartin < 042bfe9c879d-dmarc-requ...@listserv.ua.edu> wrote: > On Thu, 9 Nov 2023 16:18:17 -0600, Glenn Knickerbocker wrote: > > > >I've heard tales (probably at KTRU) of reading magnetic tape/cards with > iron filings and a loupe. > > > I believe I saw one. A flat container of ferrite slurry with a > transparent top > and a diamagnetic membrane bottom. Pressed against the tape, it clearly > showed record gaps. Reading the data would have been a challenge, > even at lowest density. > I have a can of that iron-filings-in-solvent from around 40 years ago. I havent played with it for a few years, but the solvent hadn't evaporated, and it still worked. It is indeed not feasible to read 1/2" mag tape even at 800 BPI, but what I was able to read with just a magnifying glass is the magstripe on old pre-chip credit cards. IIRC the stuff was made by (or at least branded) 3M, and was intended for (analogue) audio tape head alignment. IBM and STK CEs used it just to verify that there were data blocks, IBGs, and TMs, but not to try to read the actual data. It's a bit like looking at a CD (let alone DVD or Bluray) disk with an optical microscope. It looks about the same at almost any magnification - just shiny with colour fringes. You won't see the bits. Tony H. -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: LA vs LHI
>I know that it's model dependent and also depends on the cache loading, but >are there cases where there is a measurable performance difference between >these? > > LAY Rx,4096 > LHI Rx,4096 One aspect of the differences between the two is that LAY has a larger footprint in the i-cache since it's a 6-byte instruction vs. the 4-byte LHI. Finding / constructing a use case where that makes a measurable performance difference could be an interesting exercise. === Adam Johanson Broadcom Mainframe Software Division -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: LA vs LHI
Shmuel, I know that it's model dependent and also depends on the cache loading, but are there cases where there is a measurable performance difference between these? LAY Rx,4096 LHI Rx,4096 well, with LAY the second operand is an address with a base and an index register but LHI it is an immediate value. Guess: LAY is slower- but I doubt, that it is measurable or has been measured. And even if it is measured/measurable- does it matter with executing three or more instructions at the same time? Martin -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: Kinda fun
What bugs me about the newbies hating this "reminiscing" is they may run into a situation where they can't get something to work because they don't understand why the code has to be processed in a certain fashion. Many restrictions have been removed, but some still exist. And then there are certain people who just can't read tech English and understand it (don't start, I write manuals, and I get complaints, in fact one ISV wanted me to put in pictures for SMP/E installs, and I showed them an IBM Program Directory manual they should use as a model and they promptly rejected the idea). So back to the first sentence, this "forum" if they know where it is and can search it, may be where they will find answers in, what?, today and even more so in 10-15 years from now? And related lists such a VM_List, TSO_REXX Just say'n' Steve Thompson On 11/10/2023 4:06 AM, David L. Craig wrote: On 23Nov08:1703+, Schmitt, Michael wrote: Are we violating the "no reminiscing" rule? No, we're providing historical data for the young'uns. What's the latest that people still used punched cards and/or paper tape? In the 21st Century, I encountered an IOCP deck for a 3081 at a shop that shall remain nameless. I'll guess it was prepared ~1985. -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: Kinda fun
That beats me; the best I can do is some time in the late '80s. I read about an extension to an app we used, and sent off for it. It came in the form of a card deck, and I had to ask around to find any old card reading we might still have. There was one in one of our factories in VA, so I sent it off there in the inter-office mail and they read it in for me. Then had to link-edit it, of course. --- Bob Bridges, robhbrid...@gmail.com, cell 336 382-7313 /* ...the value we have given to [the word "Puritanism"] is one of the really solid triumphs of the last hundred years. By it we rescue annually thousands of humans from temperance, chastity and sobriety of life. -advice to a tempter, from The Screwtape Letters by C S Lewis */ -Original Message- From: IBM Mainframe Discussion List On Behalf Of David L. Craig Sent: Friday, November 10, 2023 04:07 In the 21st Century, I encountered an IOCP deck for a 3081 at a shop that shall remain nameless. I'll guess it was prepared ~1985. --- On 23Nov08:1703+, Schmitt, Michael wrote: > What's the latest that people still used punched cards and/or paper tape? -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
LA vs LHI
I know that it's model dependent and also depends on the cache loading, but are there cases where there is a measurable performance difference between these? LAY Rx,4096 LHI Rx,4096 -- Shmuel (Seymour J.) Metz http://mason.gmu.edu/~smetz3 עַם יִשְׂרָאֵל חַי -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: Kinda fun
On 23Nov08:1703+, Schmitt, Michael wrote: > Are we violating the "no reminiscing" rule? No, we're providing historical data for the young'uns. > > What's the latest that people still used punched cards and/or paper tape? In the 21st Century, I encountered an IOCP deck for a 3081 at a shop that shall remain nameless. I'll guess it was prepared ~1985. -- May the LORD God bless you exceedingly abundantly! Dave_Craig__ "So the universe is not quite as you thought it was. You'd better rearrange your beliefs, then. Because you certainly can't rearrange the universe." __--from_Nightfall_by_Asimov/Silverberg_ -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
