Comments by "Scott Franco" (@scottfranco1962) on "Low Level" channel.

  1. The classic Expo tower game. How high can you stack expos free standing on the floor without falling over. "umm... did you see what happened with all the expos from the meeting rooms?..."
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  2. From the quality of code I see generally, I believe a lot of performance improvements come from giving each program its own core. This is because the programs are looping or polling continuously waiting for conditions to end, such as a read call, a network transfer, etc. Programmers have been taught to be lazy and use so called "non-blocking" calls to get things done. The result of this is that giving such a program a dedicated core to just sit in a loop will increase overall performance because it is not getting in the way of other programs executing. I call this "burning a core" (like dropping a useless card in a card game). This mode of programming automatically limits the usefulness of adding cores. Once you have enough cores to waste on programs that parallel task inefficiently, then further cores will not help your speed.
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  3. Core meant core (originally). As in magnetic core rings.
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  4. scanf("%d", &x); Sorry, you didn't pass the interview. Leave your guest badge at the door...
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  5. I had to work on a windows driver once where the top level called lower level routines all with void pointer parameters. The original programmer believed that since the lower level didn't specify any types for its parameters, the driver was more portable. Ugghhh.
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  6. The number one hacker entry is the use of C and unprotected languages. We a seeing a pushback against that, but its peeing in the ocean.
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  7. I would say using C would be the biggest issue. Do they really use C???? Also, that don't use the heap rule. So you are exchanging heap use for lots of static array overflows, usually out in space. Great idea.
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  8.  @jonassattler4489  Yea, its an unfortunate fact that I am aware of. I am a pilot as well as a programmer. The use of C is a shockingly bad choice for life critical applications such as avionics. I disagree there are no alternatives. Java, which has been around for decades, is a fully protected language, and Pascal has been around for 50 years now. Fully protected. Allocators are well debugged. The bugs that occur happen not because of the allocator (which is usually only a page or so of code) but because of incorrect use. Regardless, again, there are languages outside of that running segment violation of a language C that properly check allocations. I use C in most of my work, have to make a living. You code in what your employer uses. But again, C is a terrible choice, and yes, there are alternatives. I have lots of issues with NASA use of COTS (Customer off the shelf). When the mars probe locked up because of a priority inversion, my first reaction was "they use a priority based RTOS???". Priority based OSes have known issues that (to me) stem from use of an oversimplified model of tasking. Demand based systems (well covered in the literature) are better and actually properly model the way tasking works. I'll put is succinctly: NASA chose their languages by popularity, not by fitness of purpose. The military went through the same thing, and they chose ADA because it had protection (long before JAVA and the protected language fad). Its simple. The military didn't want run nuclear missiles on C code. They kinda got out their on their own limb with ADA, but they made it work. ADA is still in use.
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  9. Nice, but not sure why that's better than live program debugging, ie., gdb ./inventory then crash while in gdb. Simpler and the info is the same.
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