Comment by danhor | Hacker News Reader

Comment by danhor | Hacker News Reader

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I'm not sure if you've ever used modern software. It's sometimes amazing just how unreliable it is. Web browsers crash every few weeks, windows is known for regularly needing a reboot, evince regularly crashes on me, you can't call 911 with some of cell phones, ... . This reminds me of https://danluu.com/everything-is-broken/ .

The clearest example of the difference of reliability is looking at public digital signage (on transit and elsewhere). If it's based on LED segments or something similarly basic (with old-school embedded software development) it will basically always work. New LCD Screens inside trains/busses and outside working with a modern software setup (using an OS, often with a pc architecture, quite often just displaying a website) are broken ~10%-20% of the time. Looking at (for example) busses, a large portion of the time the screen will either be blank, not display anything, old information or just wrong information. Going inside fast food restaurants with large LCDs for the menu, often something is broken, frozen or something else.

It is of course possible to make modern software more reliable. It's just much, much harder than making embedded software or PLC programming reliable. Software can be easily made more complex, but it's hard to make it non-complex or to wrap the complexity so it isn't an issue anymore. The ecosystem isn't set up for non-complexity.

I think to make software more reliable, you'd have to go back to the "waterfall" method of development.

If we went back to Dijkstra's notion of correctness by construction, then a specification for the program would be made, and then a programmer would prove their part of the code correct to the specification. They would write the precondition and postcondition of every effectful statement, document the invariant of every loop, and prove by induction that each loop does what it's supposed to do. Basically, annotate your program with Hiare triples. (There are books about how to do this). Then, extensive tests should be run for as much of rhe program as possible.

Nowadays, we have tools for this so that we don't actually have to write a proof by induction for every loop; instead, we have bounded model checkers. In theory, the manual proof writing could be isolated to the parts of the program whose properties a bounded model checker cannot verify.

However, it seems like this whole plan is infeasible unless regulations are written that enforce this onto the industry. It would make them a lot less productive, and therefore less profitable. The only benefit would be that software is more reliable. By necessity, it would have to become simpler, too. For instance, there's absolutely no way that web browsers like Chromium, with 38 million lines of code, will ever be verified, because they're too large and complex.

Such regulations exist for avionics and aerospace. They were written in blood.

> I'm not sure if you've ever used modern software. It's sometimes amazing just how unreliable it is. Web browsers crash every few weeks, windows is known for regularly needing a reboot

I'm not sure if you remember older software properly. The idea that an entire desktop computer, much less a web browser, could even run for weeks without a reboot would blow the mind of '90s me.

Netscape Navigator was the direct cause of at least 80% of the Mac OS 8/9 crashes I've experienced in my life. It was less common for the browser to entirely take down a Windows system in that era but I sure do remember seeing a lot of those application crash dialogs until the modern era of tabbed browsing made people care more about stability.

Prior to Windows 7 becoming mainstream I never had to check uptime when diagnosing weird behavior on end user computers because they just naturally got rebooted regularly. Now there are a lot of computers that only reboot when they receive updates that require one, and depending on the user might not get those updates very often. I see systems that haven't been rebooted in the better part of a year and some times longer every few weeks. Even more now with Windows 10+ "Fast Start" where "Shut Down" actually means hibernate so users who think they're shutting down every night actually haven't had a fresh boot in months.

Yep, I don't eat fast food nearly as much as I used to but whenever I go in to a place with self-service ordering "kiosks" one or more of the kiosks is often out of service or frozen up, sometimes with a Windows error screen, or just stuck in a reboot loop, or it randomly resets in the middle of entering an order.

There are trains (Polish ones, funnily enough) that will happily show you the "choose the location of this network" dialog from Windows7 on their passenger information screen.

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