[HN Gopher] Why Some Old Computers Are Interesting
       ___________________________________________________________________
        
       Why Some Old Computers Are Interesting
        
       Author : rbanffy
       Score  : 184 points
       Date   : 2021-05-24 09:03 UTC (13 hours ago)
        
 (HTM) web link (hccc.org.uk)
 (TXT) w3m dump (hccc.org.uk)
        
       | bigtimber wrote:
       | There were 4 of the then state-of-the-art, fastest in the world,
       | CDC-7600 and CDC-6600 computers installed at Lawrence Livermore
       | Lab (LLL, now LLNL, Lawrence Livermore National Lab) when I
       | worked there during the summer of 1972.
        
       | StandardFuture wrote:
       | > In fact, the operating systems that run on "old computers" are
       | surprisingly sophisticated and complex.
       | 
       | Are they? Or are we just slowly forgetting that everything in
       | modern software is composed of concepts invented pre-1980 (and in
       | fact pre-1970 for the most part)?
       | 
       | It's called "Turing's Curse" [0]
       | 
       | To clarify, it's the "surprisingly" part that is not true.
       | Certainly the software is sophisticated. What is surprising is
       | how often we think our modern software is "sophisticated".
       | 
       | [0] https://www.youtube.com/watch?v=hVZxkFAIziA
       | 
       | EDIT: but, I guess we have done some modern cool stuff with GPUs,
       | consensus algorithms including PoW, and a few cool ML model
       | architectures and training techniques.
        
         | handrous wrote:
         | We have a lot more layers of abstraction, in the name of
         | productivity. That's certainly more complex, and from a certain
         | point of view, more sophisticated.
         | 
         | Meanwhile (I can't be the only one who's noticed this?) it
         | seems like it takes a team 5x as large 2x as long to write a
         | program that does the same thing as some 80s or 90s equivalent.
         | 
         | I'm not sure what to make of that.
        
           | retrac wrote:
           | > it seems like it takes a team 5x as large 2x as long to
           | write a program that does the same thing as some 80s or 90s
           | equivalent.
           | 
           | While I can't attest to team performance, I wrote a toy
           | compiler over the long weekend here just now. There were
           | wizards who could do that 30 years ago in a weekend, of
           | course.
           | 
           | But I'm not one of them. It occurred to me that if I hadn't
           | used Haskell and some great libraries, built with a compiler
           | that takes hundreds of MB of RAM to run, and was instead
           | using C or assembly even, I'd probably still be trying to get
           | integers parsing correctly.
           | 
           | The productivity increase of modern development tools seems
           | real enough to me.
        
             | swiley wrote:
             | I've written parsers in C, you get used to it. It would
             | probably take you as long to write an integer parser in C
             | as it would take me in Haskell.
        
               | retrac wrote:
               | It's literally two lines, yet it handles hexadecimal and
               | octal too. :) Of course, if you set up some parser
               | combinators with a nice library in C, it could be a one
               | liner in C too.
               | 
               | I figure it's not the language, so much as the libraries
               | and tooling around the language. Back in the day, one
               | couldn't stick a term in the project definition, have the
               | compiler automatically download and assemble a library,
               | then invoke it with one line in the program code, all
               | within 10 seconds. You'd have to start with "is this a
               | digit?" and build up from there, like I did back in my CS
               | courses with Pascal, once upon a time.
        
         | swiley wrote:
         | I think there was a certian degree of bravery (or foolishness
         | really) that authors of older software had WRT their
         | willingness to couple with certain things (poking registers/DMA
         | with specialized hardware, monkey patching OS components etc.)
        
       | marcodiego wrote:
       | What I like about old computers: creative solutions. These
       | machines were severely limited by today standards, so to do
       | anything useful, interesting workarounds had to be developed.
       | 
       | In the home-computer field, for example, using off-the-shelf
       | cassette tape as storage, compiling code in multiple passes with
       | persistence, simpler byte-code interpreting to increase code
       | density, memory bank switching and other techniques are part of
       | the charm of using that hardware.
       | 
       | Also, it is usually impressive to watch anything useful and
       | quickly being done by constrained hardware.
        
       | rbanffy wrote:
       | One thing I always notice on the CDC 6x00 family is that the
       | vectors on screen are drawn so fast (to fit enough text on the
       | high persistence phosphor before needing to redraw) that analog
       | artifacts appear on the fonts themselves, giving them a
       | whimsical, almost Comic Sans, look.
       | 
       | Funny to see the analog side isn't able to keep up with the
       | digital hardware. That's peak Seymour Cray.
        
       | qwerty456127 wrote:
       | IMHO older computers are more interesting because you can have
       | much better relative understanding of what they consist of, how
       | do they work and and much higher relative degree of control over
       | them. They induce senses senses of curiosity, flexibility and
       | security this way.
       | 
       | Compared to the computers from the previous century which could
       | be built, modified, repaired and operated consciously, modern
       | ones are more of disposable magic-button black boxes which will
       | turn into pumpkins as soon as the vendor servers turn off and go
       | extinct like ancient magical creatures as soon as the factory in
       | Taiwan shuts down because nobody has a serious idea about all
       | their internals and how to produce them anymore.
       | 
       | Sadly, there already is a generation of programmers who aren't
       | even interested in being able to assemble their own PC from a set
       | of boards, let alone understanding anything about things like
       | registers and the physics behind them.
       | 
       | UPDATE: yes, I would say the same about cars.
        
         | mrweasel wrote:
         | I love watching retro computing channels on YouTube, and many
         | of them does such a great job of explaining CPUs like 6502,
         | 6510, Z80 or Motorola 68000. Especially the 6502 is
         | interesting, not because it's a marvel of technology, but
         | because you can learn how it work in a reasonable time frame. I
         | took university courses in computer architecture, but I can
         | explain how a modern PowerPC or AMD64 CPU work. The 6510 is
         | something I can easily follow when some guy on YouTube explains
         | how a C64 works and how he goes about debugging and repairing a
         | broken system.
        
           | coldpie wrote:
           | Probably my favorite example of this is this guy's
           | demonstration of an Altair 8800, one of the earliest PCs,
           | back when they had physical switches on the front panel which
           | you would use to manually enter machine code for the computer
           | to run. Scroll down to the bottom for the earliest videos to
           | see the introductory demonstrations. He builds on that to
           | show how data was loaded from paper punch tape, then later
           | audio cassettes and external disk storage:
           | https://www.youtube.com/user/deramp5113/videos
        
             | ilaksh wrote:
             | There is an online Altair simulator
             | https://s2js.com/altair/
        
           | Stratoscope wrote:
           | > _I took university courses in computer architecture, but I
           | can explain how a modern PowerPC or AMD64 CPU work._
           | 
           | Just to avoid possible confusion, I think you meant "I _can
           | 't_ explain", is that right?
        
         | canadianfella wrote:
         | > Sadly, there already is a generation of programmers who
         | aren't even interested in being able to assemble their own PC
         | from a set of boards
         | 
         | Why is this sad? Is it sad when cab drivers buy new cars
         | instead of kit cars?
        
         | m463 wrote:
         | I think it's all state-of-the-art vs grassroots-tech-tree
         | 
         | Meaning - the state of the art stuff can't be explored by
         | normal people, but over time the knowledge and tools trickle
         | down and it becomes democratized.
         | 
         | Older cars were accessible to shadetree mechanics, who could
         | work on most stuff. When they became electronic, it cut some
         | people off... until things like canbus became known, and later
         | tools became generally available to folks with a laptop.
         | 
         | Only twist nowadays is manufacturers are actively preventing
         | some things through cryptographic signatures and the like.
         | Hopefully, eventually, this will get tools to allow people to
         | mess with things.
        
         | jhvkjhk wrote:
         | No need to sad, with the rise of RISC-V and the help of FPGA,
         | many CS students nowadays take writing a soft core CPU as a
         | hobby.
         | 
         | When RISC-V and open source FPGA toolchain become more popular,
         | I guess more and more programmers will come back to play with
         | hardware.
        
           | birktj wrote:
           | I have been looking for a cheap fpga devboard for this sort
           | of thing, but results have been somewhat disappointing. The
           | tinyfpgas look great but have been sold out for a long time.
           | I have seen some interesting ones on tindie but the selection
           | is quite limited. Does anyone here have any good pointers?
           | (Plus for one with a hand-solderable fpga)
        
             | colejohnson66 wrote:
             | The iCE40 from Lattice is pretty popular for its open
             | source (reverse engineered) toolchain.
             | 
             | As far as hand soldering an FPGA, you're gonna have a hard
             | time finding _any_ that aren't BGA simply because of all
             | the IO. They exist, but probably not in dev board form as
             | they're really limited in IO and cells.
        
               | [deleted]
        
             | sigstoat wrote:
             | the iCE40HX4K is available in TQFP-144, which can be
             | reliably hand soldered after some youtube videos and
             | practice.
             | 
             | i think there are still xilinx CPLDs in TQFP too.
             | 
             | should be boards floating around for any of them. if not,
             | well, only reason you'd want to hand solder it is because
             | you're making your own board. a simple dev board is great
             | practice to make sure you've got your package correct.
        
             | nobodywasishere wrote:
             | I like and use the Upduino 3.0
        
       | chaoticmass wrote:
       | What is "interesting" obviously depends on the person. I always
       | liked playing with old *nix workstations from the 90's. Something
       | about tinkering on a box that would have cost over $50,000 new is
       | interesting to me.
        
       | nix23 wrote:
       | I someone wants to test MVS-TK4- or VM370 here some resources:
       | 
       | UpToDate MVS distribution: http://wotho.ethz.ch/tk4-/
       | 
       | UpToDate vm370 distribution: http://vm370.org/VM/V1R1.1
       | 
       | 390 Emulator: https://github.com/SDL-Hercules-390/hyperion
       | 
       | Best 3270-Terminal for windows:
       | http://www.tombrennansoftware.com/download.html
       | 
       | 3270-Terminal for *nix or Win: http://x3270.bgp.nu/
        
         | rbanffy wrote:
         | I need to put up a new Docker image for my VM/370 thing at
         | https://hub.docker.com/r/rbanffy/vm370.
         | 
         | I wonder if my 3270 font would work with Vista tn3270... It
         | doesn't with x3270 :-(
        
       | hulitu wrote:
       | Because the SGI cases or SUN pizza boxes are unforgettable. Now
       | computer cases are just disgusting.
        
       | Taniwha wrote:
       | Ah IBM Stretch - first (only?) computer fixed by giving it an oil
       | change .....
       | 
       | http://www.chilton-computing.org.uk/acl/literature/reports/p...
        
         | ecpottinger wrote:
         | The college I went to had air cooled tape drives. For some
         | reason one unit would get too hot and stop working.
         | 
         | Solution: Go behind it and flap the large access door a couple
         | of times, and then it would start up and finish a compile. As
         | you were waiting for the printouts it would keep cooling down
         | and do the next job if it was not too long.
        
       | dekhn wrote:
       | My favorite old computer is the Mark I perceptron, which was a
       | neural network hardware computer (single layer) with light-
       | sensitive visual receptors, weights controlled by self-turning
       | potentiometers, and maually wired full connectivity:
       | https://en.wikipedia.org/wiki/File:Mark_I_perceptron.jpeg
        
       | TristanBall wrote:
       | So, I guess video and network cards are the two most common
       | remaining components that could be called "peripheral
       | processors"?
       | 
       | My interpretation of the ( frustratingly sparse ) documentation
       | for the AWS Nitro hardware support seems to imply that it's
       | pushed a bit more of the processing back out to the peripherals -
       | which seems to buck the trend, but also seems highly effective.
       | 
       | For example, so far as I can tell, AWS's NVME drives have a lower
       | latency from within a Nitro EC2 vm than a 905P Optane accessed
       | from a KVM VM with PCIE passthrough on my play machine at home -
       | although it's possible I've done something wrong with the setup!
        
       | KozmoNau7 wrote:
       | What has always fascinated me about old hardware/software is the
       | "what if" aspect.
       | 
       | Up until mid-90s, there was a real diversity of ideas and
       | architectures in computing. 68K, PPC, x86, RISC, ARM, MIPS, i860,
       | and I'm forgetting a lot of others. There were a lot of
       | interesting ideas, some of which did become standard, while
       | others died either for technical reasons (lack of adequate 3D
       | capability on the Amiga) or because of business deals that didn't
       | pan out (such as BeOS on Macintosh being dumped in favor of
       | buying out NeXT).
       | 
       | Of course x86 seems standard and humdrum today, but it wasn't
       | necessarily meant to be that way.
       | 
       | We could have been running BeOS on i860-based hardware, with
       | MiniDiscs for removable storage, if things had panned out
       | differently. And I find that fascinating to consider, when
       | examining old computers.
        
         | bombcar wrote:
         | Even further back and you find that so many things we take for
         | granted were just one of many options. Things I can think of
         | offhand:
         | 
         | 1. 8-bit bytes (7,6,9 were common) 2. Byte-level addressing
         | (word addressing was common) 3. One's complement
        
         | mrweasel wrote:
         | > with MiniDiscs for removable storage
         | 
         | I wonder why that never amounted to anything. If I recall a few
         | drives was made, but the cost just meant they where out of
         | reach. The disc was just so cool, like take out of a sci-fi.
        
           | cogman10 wrote:
           | They were pretty popular in the EU circa 2004ish. A lot of
           | people used them for MP3 storage.
           | 
           | I think what killed them was ultimately the iPod.
        
             | KozmoNau7 wrote:
             | Minidiscs for music were very popular before MP3 players
             | had reasonable storage space, at least here in Denmark and
             | AFAIK in most of Europe, and obviously in Japan.
             | 
             | If you had to pick between an MP3 player with 32MB or maybe
             | 64MB of fixed internal memory, or a Minidisc player where
             | each disc could hold a full CD album and you could swap
             | them as easily as a CD or a floppy disk, the choice was
             | pretty clear, especially when you looked at it as a logical
             | progression from a discman. The ATRAC codec is a mostly-OK
             | lossy codec. Not full CD quality, but it was comparable to
             | MP3 at the time.
             | 
             | (Minidiscs never supported MP3 until right at the end of
             | Hi-MD, otherwise they were ATRAC and eventually CD-quality
             | PCM only.)
             | 
             | The final iteration (Hi-MD) could hold 1GB of data or 94
             | minutes of full CD-quality uncompressed PCM audio, but that
             | was too little and too late when it came out in 2004.
             | 
             | As for using Minidisc for _data_ , that was a slightly
             | different kettle of fish. The format was absolutely capable
             | of doing it and the original discs could hold 140MB
             | (increasing with later format revisions), which would have
             | been absolutely groundbreaking in the early 90s. _All_ of
             | the technology was mature and proven and fully capable of
             | displacing both the floppy disc and the CD. This was before
             | the Zip disk, with higher storage capacity and actually
             | reliable. The magneto-optical Minidisc could theoretically
             | be rewritten millions of times, and sure each disc was a
             | bit expensive initially, but they were super durable with a
             | tough plastic shell, and 140MB of storage was more than a
             | lot of people 's home computers had at the time.
             | 
             | Unfortunately the record label arm of Sony were terrified
             | of organized illegal copying and distribution, and because
             | everyone was generally stuck in a mindset of seeing
             | Minidisc as a cassette tape replacement rather than a
             | general data storage format, it was stuck with real-time
             | dubbing only (some devices with integrated CD and MD
             | players offered high-speed dubbing, but it was still just
             | dubbing, not data transfer). It didn't get data storage
             | capability until the Hi-MD in 2004, which again was too
             | little too late.
             | 
             | Combined with Sony's general insistence on keeping their
             | formats proprietary and locked down (see Memory Stick, UMD,
             | Betamax, DAT and so on), everything just conspired to not
             | let the technical capabilities of Minidisc come to
             | fruition.
             | 
             | There was an MD Data format, but it never really got off
             | the ground. It used special incompatible MD Data discs,
             | which were rare and expensive, plus the drives themselves
             | were big, clunky and expensive.
             | 
             | Minidisc was legitimately a big hit for a while, for
             | portable music. But it never quite displaced the CD and it
             | never became the data storage format it could have been.
             | And now we've got cheap flash memory, so even the idea of a
             | magneto-optical disc seems a bit quaint and antiquated.
        
             | sumtechguy wrote:
             | Also around that era a usb drive of comparable size was
             | available and pretty much worked with all computers for
             | similar price points.
        
             | mrweasel wrote:
             | I actually have one family member that uses mini-discs.
             | Mostly to listen to older stuff that she only have on mini-
             | disc, but that's also an indication of how durable those
             | things are. Getting new mini-discs plays is however getting
             | extremely difficult, and expensive.
        
       | EvanAnderson wrote:
       | I'll throw out a reference to the Burroughs "large systems" line:
       | https://en.wikipedia.org/wiki/Burroughs_large_systems
       | 
       | These are the lineage of machines Knuth implemented his famous
       | ALGOL-60 compiler on. There's a nice video about the B6500 that
       | was discussed on HN years ago:
       | https://news.ycombinator.com/item?id=7880027
       | 
       | I did some work adjacent to a UNISYS ClearPath "A Series" machine
       | and later a PC-based version back in the early 2000s. Watching
       | the operators and field service technicians working on it I got a
       | feeling of a very mature environment. (Not necessarily fun to use
       | by the look of it.) I got a bit of an IBM AS/400 feeling watching
       | users interact with it in terminal emulation. For somebody with a
       | Unix and MS-DOS background it just seemed odd.
       | 
       | After that contract was up I mostly forgot about it. I heard a
       | talk where Alan Kay referred to some old Burroughs system. I got
       | to reading about Burroughs and learned UNISYS was a successor.
       | That led down a rabbit hole that ended up at these
       | B5000-descended machines.
       | 
       | It looks like it was a well thought-out architecture that
       | persists today (albeit in software, rather than hardware). The
       | operating system, MCP, is still under development.
        
         | rbanffy wrote:
         | > The operating system, MCP, is still under development.
         | 
         | MCP is, by far, the most user hostile OS I've ever seen. It's
         | no surprise Bonnie McBird, who wrote Tron's screenplay and is
         | Kay's wife, used it as the name of the villain.
        
           | mrandish wrote:
           | There were a few other possible tie-in. The word TRON itself
           | was a command in several MSFT Basic interpreters of the 8 bit
           | era. It was short for TRACE ON and its companion for TRACE
           | Off was TROFF. They shortened strings because space was
           | limited in the 8K ROM.
           | 
           | Good times...
        
           | cmrdporcupine wrote:
           | Holy crap, I had no idea that the screenwriter for Tron was
           | connected to Alan Kay. Thanks for that tidbit. Sounds like
           | she became romantically connected to him after meeting him
           | while researching the movie. Neat.
           | 
           | I'd love to see her original script before it got ruined.
           | Sounds like her and Kay were pretty bitter about it.
           | 
           | https://web.archive.org/web/20030109182549/http://www.tron-s.
           | ..
        
             | rbanffy wrote:
             | I'm not sure I'd like her take. I don't like too much the
             | movie either. I'd like the programs to be more alien, more
             | funhouse mirror images of their creators, and be portrayed
             | as AI semi-autonomous agents.
             | 
             | But that'd be a lot to demand on that age. They already had
             | artificial life for their credits and that's impressively
             | prescient.
        
           | spiritplumber wrote:
           | ... That is officially awesome. End of line.
        
       | gnufx wrote:
       | It's normally worth reviewing original work in a field for
       | understanding and lessons. Some current work inspired by the 6600
       | from all those decades ago is https://www.crowdsupply.com/libre-
       | risc-v/m-class/updates/mod...
        
       | rbanffy wrote:
       | > But the PP concept and the offloading of the OS from the main
       | CPU is still a very interesting idea - and one which is unlikely
       | to be explored in foreseeable future machines.
       | 
       | Interestingly, a lot of the system services on macOS run on the
       | power efficient but slow cores on the M1, keeping the beefy cores
       | to user applications. I wonder if Linux can have an attribute for
       | executables that indicate a preference of which kind or processor
       | it should be preferably scheduled to.
        
         | yjftsjthsd-h wrote:
         | Could always just sort processes to cores by nice value.
        
           | rbanffy wrote:
           | Can the kernel do it transparently on asymmetric core
           | machines? Intel did show one some time ago and you can kind
           | of manufacture cores with bigger caches and more execution
           | ports by turning off SMT for them, turning an 8-core x86 into
           | 8 "cores" with smaller cache and another 4 with twices as
           | much L1.
        
             | toast0 wrote:
             | I don't think you can be totally transparent; [1] if the
             | cores are really asymmetric, there will likely be timing
             | differences. But, you could certainly do things like if
             | only the big cores support AVX, indicate AVX support to the
             | program, and if it's running on the little core when it
             | hits an AVX instruction, the kernel handles the invalid
             | operation fault by rescheduling it to run on the large
             | core.
             | 
             | If the program does a bunch of AVX once in a while, that
             | can work well. If it's mostly AVX, and multithreaded, then
             | you might likely spawn too many threads. If it's like one
             | AVX instruction in each loop, that would also tend to be
             | bad.
             | 
             | Balancing load would probably be a lot trickier than with
             | SMP, but today's SMP is already tricky because frequency
             | changes with the number of cores in use; it's not always
             | optimum to run N threads on N cores anyway.
             | 
             | [1] and really, I think this meaning of transparent is
             | really opaque; you don't want the program to know what core
             | type it's running on.
        
               | rbanffy wrote:
               | I think the best way would be two different approaches.
               | One, perhaps based on nice values or other priorities,
               | that would push scheduling to the smaller cores and one,
               | one-way, where some form of program metadata indicates
               | which kind of core would be optimally suited to run it
               | without the program having any awareness of it.
        
       | dhosek wrote:
       | 370 assembly language was interesting in so many ways.
       | Applications were responsible for maintaining their own call
       | stack and there were processor-level instructions for converting
       | a number encoded in EBCDIC and converting it to a machine level
       | int.
        
         | ilaksh wrote:
         | This is only just slightly related, but I am working on a
         | project based on Algorand, and one of the interesting things
         | about it is that the smart contracts are written in something
         | somewhat like an assembly language. It actually is deliberately
         | not Turing complete because it does not allow looping or
         | recursion, but has a few interesting features and constraints.
         | 
         | For example, it has built-in cryptography instructions.
         | 
         | The need to execute as many "programs" as possible to have a
         | high transaction rate has pushed the design towards these
         | intriguing constraints.
        
       | bullen wrote:
       | Whenever people talk about old computers I need to mention the
       | C64 that really laid the foundation for PCs today, new releases
       | are coming every day: http://csdb.dk
        
       | fortyrod wrote:
       | The university I went to had used Xerox Sigma 6/7/9s. One of them
       | is now in the living computer museum. Yeah! After programming
       | 6502 assembler in high school, having multiple blocks of 16
       | 32-bit registers was breath-taking. My brain was wired to the
       | 6502 X/Y/A thing so I doubt I ever used more than 5-6 of them at
       | a time. After doing a lot of 8-bit micro and X86 assembly, doing
       | ARM assembly for the first time felt similarly freeing.
        
       | agumonkey wrote:
       | Most things are interesting simply due to the fact that they were
       | produced by and through the constraints of their time. Seeing how
       | people solved these contextual problems very often is
       | fascinating. And then there's the spirit/aesthetics/goals of the
       | era.
        
         | nomoreusernames wrote:
         | its why the demoscene is not what it used to be :)
        
           | agumonkey wrote:
           | I think we were touching this subject on another thread about
           | Japanese samplers (AKAI MPC), where technology becomes so
           | capable there's no challenge.
        
             | Kye wrote:
             | Breakbeats basically came about as a way to overcome the
             | limits of early samplers. A competition to invent the
             | spiciest Amen break slice.
        
       | limbicsystem wrote:
       | Old computer systems are fascinating from many points of view:
       | The article discusses the software used to wring the last drop of
       | performance out of hardware that we would probably now consider
       | to be inadequate for running a disk controller. It's super cool
       | that many of these systems are now available as emulators! I was
       | a little surprised that the author only got twice the performance
       | of the DtCyber in an emulator until I saw that they were
       | emulating on an 800MHz P3 :)
       | 
       | In addition, visiting these old devices IRL is pretty
       | instructive: one thing that always strikes me when I visit the
       | Computer Sheds in Yorkshire (http://www.computermuseum.org.uk/ -
       | an absolute gem BTW) is the enduring problem of thermal
       | management. Up close, those old mainframes are basically huge air
       | conditioning systems with some chips attached. My understanding
       | is that managing heat is >still< the ultimate factor limiting
       | performance (otherwise we could just stack up silicon in 3D)...
        
         | BuildTheRobots wrote:
         | > hardware that we would probably now consider to be inadequate
         | for running a disk controller.
         | 
         | Wasn't the disk controller chip in the BBC Micro significantly
         | more powerful than the main CPU? I think some games used it as
         | a coprocessor.
        
           | rbanffy wrote:
           | That's ludicrous. The 6502 is the best 8-bit processor that
           | ever existed ;-)
           | 
           | Now, on a more serious tone, any processor in the machine you
           | could detect could be used to offload some processing from
           | the CPU. I wonder if that wasn't done with 1541 or 1571
           | Commodore floppy drives. I know there was software that wrote
           | new functionality onto the drive's memory to make disk IO
           | faster.
           | 
           | With enough memory, you could sort a text file and write the
           | output to a new file without ever bothering the CPU. I don't
           | think that was ever actually done, but the drives also ran
           | 6502 processors, and the 1571 ran at twice the main
           | computer's clock.
        
             | pkroll wrote:
             | The 1571 was the drive meant for the C-128, which could
             | also run at double speed (2 megahertz!) with the C-64 video
             | chip disabled and the 80-column video running.
        
             | ecpottinger wrote:
             | One thing you could setup on the Commodore drives is file
             | copying from on drive to another without it going thru the
             | computer, they just talked to each other. You could also do
             | the same thing if you had a straight text file and sent it
             | to the printer (I am not sure which printer models) with
             | again not using the computer after the handshaking was set
             | up.
        
             | tenebrisalietum wrote:
             | On the C64/1541 you could definitely upload code to one or
             | more of the 256-byte 1541 disk buffers and make the drive
             | execute it. The problem is you have 3 pins to transmit your
             | data and those are not connected to any communication
             | facility like an ACIA - you have no choice but to involve
             | the CPU in some bit banging there.
             | 
             | The 1571 used the burst mode of the CIA IIRC (also IIRC it
             | wasn't done in the 1541 to be compatible with the VIC20) so
             | there were more possibilities there.
        
               | rbanffy wrote:
               | > The problem is you have 3 pins to transmit your data
               | (...) you have no choice but to involve the CPU in some
               | bit banging there.
               | 
               | Well... As long as the code takes longer to compute than
               | it takes to push/pull the data, it's still a win.
               | 
               | I really can't think of any practical usage, of course.
               | Maybe transforming ASCII files to EBCDIC ones without
               | involving the CPU, or generating CRC32 values for the
               | files on disk.
        
               | ecpottinger wrote:
               | Did not fast loaders for the drive put a small program on
               | the disk drive?
        
             | BuildTheRobots wrote:
             | There's every chance I'm remembering it wrong - the double
             | the clock speed certainly rings a bell. Got a weekly video
             | call with a friend who still regularly hacks on a Beeb, so
             | will try and clarify and update my comment tomorrow :)
        
               | rbanffy wrote:
               | The Beeb and the Ataris ran at 2 MHz. Apple II, VIC-20,
               | C64, and 1541 all ran at 1 MHz. The 1571 ran at 2 MHz,
               | same as the C128 (except when pretending to be a 64)
        
               | forinti wrote:
               | The beeb had an additional advantage: RAM ran at 4MHz, so
               | the CPU and the video chip didn't have to compete for
               | access.
        
               | bullen wrote:
               | Same for the C64... RAM at twice the Hz so the 6510 and
               | SID/VIC-2 accessed it interleaved.
        
         | Stratoscope wrote:
         | > _My understanding is that managing heat is >still< the
         | ultimate factor limiting performance_
         | 
         | It seems fitting that I'm hearing the fans spin up to full
         | blast on my ThinkPad X1 Extreme laptop supercomputer as I
         | compile some code in an Ubuntu VM while starting up a CPU-
         | hungry Point Of Sale system in a Windows VM, and reading your
         | comment on the Windows host OS.
         | 
         | It is nice that I can step away from the computer and just
         | listen for the fans to quiet down again to tell when everything
         | is ready to go.
        
           | bserge wrote:
           | Are you monitoring temperatures on it?
        
             | Stratoscope wrote:
             | Not specifically, but the top of the keyboard does get warm
             | when all this is going on. Do you or anyone have any
             | recommendations for temperature monitoring software for a
             | ThinkPad running Windows with various other OSes in VMs?
             | 
             | In any case I think the POS software may be the main
             | culprit, as it normally runs on a standalone machine and
             | wasn't designed for power savings. I did set the Windows VM
             | it runs in to "Power saver" but it doesn't seem to have
             | helped much.
             | 
             | (Sorry if this is off topic for the thread!)
        
               | nix23 wrote:
               | Have you activated VT-x VT-d etc in the bios?
               | 
               | If not prepare for a performance boost, and a quiet Fan
               | ;)
        
               | Stratoscope wrote:
               | Thanks for the tip. Yeah, "Intel Virtualization
               | Technology" and "Intel VT-d Feature" are both enabled by
               | default in the BIOS (in fact it doesn't let you turn them
               | off).
        
               | nix23 wrote:
               | Ah ok, i have seen some bios's where both are deactivated
               | plus hyper-threading too :)
        
               | bserge wrote:
               | NotebookFanControl is the only one that works on newer
               | machines in my experience.
               | 
               | https://github.com/hirschmann/nbfc
               | 
               | I'm asking because I'm wondering how often it hits 99
               | degrees and throttles. And if it doesn't, I really need
               | to take a closer look at it, because that would be
               | incredible.
               | 
               | Dell and HP machines have this problem, 6 core Intel
               | processors run _slower_ than 4 core ones because the
               | former always throttle (even though the TDP is supposedly
               | the same).
               | 
               | If you want, you can use Throttlestop to set better
               | controls/limits on clocks and power (and possibly
               | undervolt it) for better performance, battery life and
               | temperatures.
        
               | ahelwer wrote:
               | I don't have a thinkpad, but I like OpenHardwareMonitor
               | for my computers: https://openhardwaremonitor.org/
        
               | mobilio wrote:
               | I'm using ArgusMonitor for this:
               | https://www.argusmonitor.com
        
               | listic wrote:
               | SpeedFan? https://almico.com/speedfan.php
        
           | p_l wrote:
           | Well, at least it's Thinkpad X1E...
           | 
           | We had much less going on when we joked that you know who is
           | compiling or running any sort of serious work in the office
           | by hearing whose MBP was whining hard with its fans.
        
             | Stratoscope wrote:
             | Ah yes, these fans may get loud, but they are nothing like
             | an office back in the day full of hackers on ASR-33
             | Teletypes!
             | 
             | Each one had a noisy keyboard and a noisy printer. The
             | keyboard didn't have a nice click like a modern keyboard,
             | more of a loud scrunchy sound. The printer was even louder
             | and rang a bell if you had a line too long.
             | 
             | You could always tell when the mainframe crashed.
             | Everyone's Teletype printer stopped all at once, and
             | everyone started mashing down every key on their keyboard
             | out of frustration.
        
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