I'm ambivalent about Rust these days.
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As an example of the kind of processor I'm thinking of, consider the Microchip (formerly Atmel) SAMA5 family. Single-core Cortex-A5 at 500 MHz, benchmarking at 722 DMIPS on the evaluation board I recently ordered (yes, I've gone far down this rabbit hole), with 128 or 256 MB of RAM in typical configurations. The practicality of achieving 15 hours of battery life on a 2000 mAh battery has been directly validated by this SoC family's use in the HumanWare Mantis Q40 Braille display/note-taker.
7/?
That Mantis is running a closed software stack on a SAMA5D3 SoC. It primarily acts as a Braille terminal for a PC or mainstream mobile device, and also has a handful of other applications, including a book reader that can download books over WiFi. But it could *be* a personal computer all by itself; it's already running Linux. Yes, it would be a personal computer with CPU performance somewhere in the neighborhood of a Pentium II. But we used to do real personal computing on those.
8/?
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That Mantis is running a closed software stack on a SAMA5D3 SoC. It primarily acts as a Braille terminal for a PC or mainstream mobile device, and also has a handful of other applications, including a book reader that can download books over WiFi. But it could *be* a personal computer all by itself; it's already running Linux. Yes, it would be a personal computer with CPU performance somewhere in the neighborhood of a Pentium II. But we used to do real personal computing on those.
8/?
Like I said, I already ordered a SAMA5 evaluation board, specifically the SAMA5D27 WLSOM1 evaluation kit, with 256 MB of RAM. I got Alpine Linux running on it. It can compile C. Slowly, yes; compiling CPython (default configuration with only base development packages) took 3.5 hours. But still, it finished, without running out of memory or thrashing endlessly. When I tried compiling a small Rust application, it took long enough just to compile the syn crate that I gave up.
9/?
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P pixelate@tweesecake.social shared this topic
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As an example of the kind of processor I'm thinking of, consider the Microchip (formerly Atmel) SAMA5 family. Single-core Cortex-A5 at 500 MHz, benchmarking at 722 DMIPS on the evaluation board I recently ordered (yes, I've gone far down this rabbit hole), with 128 or 256 MB of RAM in typical configurations. The practicality of achieving 15 hours of battery life on a 2000 mAh battery has been directly validated by this SoC family's use in the HumanWare Mantis Q40 Braille display/note-taker.
7/?
@matt ooooo you're doing work with the same SoC I am thinking of using for my mesh phone project
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@matt ooooo you're doing work with the same SoC I am thinking of using for my mesh phone project
@freya Seriously? OK, I'm not crazy for using this SoC in 2026.
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Like I said, I already ordered a SAMA5 evaluation board, specifically the SAMA5D27 WLSOM1 evaluation kit, with 256 MB of RAM. I got Alpine Linux running on it. It can compile C. Slowly, yes; compiling CPython (default configuration with only base development packages) took 3.5 hours. But still, it finished, without running out of memory or thrashing endlessly. When I tried compiling a small Rust application, it took long enough just to compile the syn crate that I gave up.
9/?
So, we could have a general-purpose personal computer that runs for 15 hours on a 2000 mAh battery. Maybe more with TTS output rather than a Braille display; I gather that Braille displays are fairly power-hungry because of all the pins moving up and down. But I believe that a general-purpose personal computer needs to be good for modifying its own software, at all levels of the stack. Rust fails hard on that criterion on this low-power CPU that has performance that used to be good.
10/?
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@freya Seriously? OK, I'm not crazy for using this SoC in 2026.
@matt fuck no. look at the security features, onboard secure element and eFuses and such on some of them. I'm pretty sure that's an SoC that's covered by the CIP-LTS Linux kernel, which is what I plan to use in my device to avoid the "woops your bsp is no longer supported, fuck your updates" problem. specs I'm thinking. SAMA5D27 536MHz, 256MiB ram, 256MiB flash for OS, 4GB flash for apps and data. qwerty keyboard, D-pad, trackwheel, 2.8-inch 320x240 LCD. screenreader, obviously. custom UI layer because xorg and Wayland for this are both bad. the radio stack is SX1262 LoRa and MM8108 Wi-Fi HaLow, the former for device-to-device messaging, the latter for connection to a federated, independent, solar-powerable mesh mobile network I've been designing, based on Intel N100 base stations on lampposts and stuff. it initially started as "what if I make an accessible meshtastic device?" and expanded out to "what if we made an accessible, non-touchscreen, E2EE, federated smartphone platform, based on a mid 2000s blackberry formfactor, a device very good at making very secure communication very simple and reliable, and very not optimised for anything else?"
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So, we could have a general-purpose personal computer that runs for 15 hours on a 2000 mAh battery. Maybe more with TTS output rather than a Braille display; I gather that Braille displays are fairly power-hungry because of all the pins moving up and down. But I believe that a general-purpose personal computer needs to be good for modifying its own software, at all levels of the stack. Rust fails hard on that criterion on this low-power CPU that has performance that used to be good.
10/?
So, do I want to go back to writing, and encouraging others to write, software in C? Absolutely not. I'm convinced by the arguments that memory safety by default, that can be checked by machine rather than requiring constant programmer discipline, is a moral imperative, considering the consequences of memory safety vulnerabilities for security and privacy.
11/?
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That Mantis is running a closed software stack on a SAMA5D3 SoC. It primarily acts as a Braille terminal for a PC or mainstream mobile device, and also has a handful of other applications, including a book reader that can download books over WiFi. But it could *be* a personal computer all by itself; it's already running Linux. Yes, it would be a personal computer with CPU performance somewhere in the neighborhood of a Pentium II. But we used to do real personal computing on those.
8/?
@matt my first Linux box was a 166MHz Cyrix 6x86 (so, much slower floating point than a Pentium or AMD at the same clock, but, pin compatible and similar instruction set, I think). It was a huge jump up from the Amiga 3000 I had before, and very usable for all sorts of things. I am pretty spoiled in terms of compute now, but I was writing software (well, learning to write software) on that machine. But, yeah, can't run a modern Linux or build Rust apps in 64MB. Maybe Zig, though?
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So, do I want to go back to writing, and encouraging others to write, software in C? Absolutely not. I'm convinced by the arguments that memory safety by default, that can be checked by machine rather than requiring constant programmer discipline, is a moral imperative, considering the consequences of memory safety vulnerabilities for security and privacy.
11/?
So do we have to accept that some level of computing power well above that of a Pentium II is simply the baseline for a modern general-purpose computer? Maybe. Perhaps the idea of something like the Mantis Braille display, with its battery efficiency, being a general-purpose personal computer is simply an impossible dream that I have to let go of. But, that was always an extreme example anyway.
12/?
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So, we could have a general-purpose personal computer that runs for 15 hours on a 2000 mAh battery. Maybe more with TTS output rather than a Braille display; I gather that Braille displays are fairly power-hungry because of all the pins moving up and down. But I believe that a general-purpose personal computer needs to be good for modifying its own software, at all levels of the stack. Rust fails hard on that criterion on this low-power CPU that has performance that used to be good.
10/?
@matt maybe gccrs (when it’s ready) will be less resource hungry. There is also Mutabah’s compiler you can try now.
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@matt my first Linux box was a 166MHz Cyrix 6x86 (so, much slower floating point than a Pentium or AMD at the same clock, but, pin compatible and similar instruction set, I think). It was a huge jump up from the Amiga 3000 I had before, and very usable for all sorts of things. I am pretty spoiled in terms of compute now, but I was writing software (well, learning to write software) on that machine. But, yeah, can't run a modern Linux or build Rust apps in 64MB. Maybe Zig, though?
@swelljoe My first Linux box was a 486SX at 33 MHz in 1996. I think I put Linux on it when it still had only 4 MB of RAM. Hard to believe you could actually compile real C code, including the kernel, on that little.
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So do we have to accept that some level of computing power well above that of a Pentium II is simply the baseline for a modern general-purpose computer? Maybe. Perhaps the idea of something like the Mantis Braille display, with its battery efficiency, being a general-purpose personal computer is simply an impossible dream that I have to let go of. But, that was always an extreme example anyway.
12/?
Were there other paths to a software stack with minimal unsafe code at the bottom that required far fewer machine resources to compile, that the industry chose not to take? Maybe the Rust Graydon wanted that had no future (https://graydon2.dreamwidth.org/307291.html)? I guess it's kind of moot, because the industry didn't take one of those paths, meaning there's no big library ecosystem on which to build, say, a new personal computing platform with a TTS/Braille-first UI framework.
13/?
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@inkreas.ing How long does a release build take?
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Were there other paths to a software stack with minimal unsafe code at the bottom that required far fewer machine resources to compile, that the industry chose not to take? Maybe the Rust Graydon wanted that had no future (https://graydon2.dreamwidth.org/307291.html)? I guess it's kind of moot, because the industry didn't take one of those paths, meaning there's no big library ecosystem on which to build, say, a new personal computing platform with a TTS/Braille-first UI framework.
13/?
OK, I guess Rust compile time isn't so bad on older computers that people actually use as personal computers. See this reply that came in from Bluesky. https://bsky.app/profile/did:plc:54jgbo4psy24qu2bk4njtpc4/post/3mlptu6oycc2g 5 seconds for a debug build on a 2009 MacBook. I feel better now.
14/?
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@inkreas.ing What CPU model does that MacBook have? And how much RAM? Thanks.
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So, we could have a general-purpose personal computer that runs for 15 hours on a 2000 mAh battery. Maybe more with TTS output rather than a Braille display; I gather that Braille displays are fairly power-hungry because of all the pins moving up and down. But I believe that a general-purpose personal computer needs to be good for modifying its own software, at all levels of the stack. Rust fails hard on that criterion on this low-power CPU that has performance that used to be good.
10/?
@matt that's cool. I run primarily 100 percent with Braille unless Braille just won't read something.
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@swelljoe My first Linux box was a 486SX at 33 MHz in 1996. I think I put Linux on it when it still had only 4 MB of RAM. Hard to believe you could actually compile real C code, including the kernel, on that little.
@matt I had the Amiga C compiler Matt Dillon (of FreeBSD and Dragon BSD) made and I tinkered with it. I think I used it as far back as the Amiga 2000, which I think only had 1MB. I probably upgraded it in some way, but don't remember details, probably 2MB. The 3000 used weird ass ZIP RAM, and I distinctly remember I upgraded it to 8MB. But, I'm confident I wouldn't enjoy working with those kind of limitations for serious programming.
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OK, I guess Rust compile time isn't so bad on older computers that people actually use as personal computers. See this reply that came in from Bluesky. https://bsky.app/profile/did:plc:54jgbo4psy24qu2bk4njtpc4/post/3mlptu6oycc2g 5 seconds for a debug build on a 2009 MacBook. I feel better now.
14/?
Still, I can't help but wonder. Consider a counterfactual where the original ARM processor, the one that famously ran on about 100 mW (meaning that it could, by accident, run only on leakage current), had shipped in a personal computer that had been wildly successful, and it then became an industry norm that all personal computers going forward simply must use that little power. Where would we be now? Still writing large amounts of unsafe C code? Or would we have found a different path?
15/?
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@inkreas.ing I gather that incremental build is a debug build? If so, do you find that, for a desktop application using an all-Rust GUI stack, the debug build is noticeably slower than the release build on that 2009 MacBook?
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@inkreas.ing Was Rust compilation in particular painful before you upgraded the RAM to 8 GB?
