Very true - decision quality is super important! My point here is that trust erodes in the absence of good communication, and when that happens, your decisions matter less because you won‘t be able to deliver on them as effectively.
In your other point though, I‘ve seen highly effective managers who didn‘t understand much of what the team was doing technically, because the were able to build trust among everyone involved in major processes.
The text really captured my attention. I've recently been struggling with whether or not tech and the modern internet are a force for good. I always enjoyed tinkering with hardware and software, and have been working in related jobs because it pays well and there are always interesting challenges to solve. But the societal shifts ongoing in Europe, the filter bubbles and breaking down of discourse, the xenophobia and the growing divide between large parts of society as well as the erosion of (local) media and the crisis of mental well-being among both adults and adolescents, which I feel are at least partly attributable to technological changes in the past ten years, have led me to think that maybe the most important thing for people right now may be spaces without technology, without personalization and just being confronted with the community of others. This does not seem like a problem solvable by the means of technology and makes me wonder whether I've spent my life learning about technology only to abandon it at some point.
Are there any good resources about what I call my "tech hangover" to navigate how to move on, maybe convert this education into something of societal value beyond screens? Or am I being too cynical about everything and in reality it's all much better than I'm seeing it? Open for anything here really, but struggling with the status quo.
It feels to me that overall people are quitting their corporate jobs and searching for meaningful and impactful things to do professionally. There are some movements which are trying to do something like AI for good, but it seems like generally people know that "something is not right"
Sure, although I'm not sure how helpful the answer will be as I'm still trying to figure things out myself :)
After I quit my job in 2017, I floundered for a bit while living off of my savings. Later that year, the big crypto bull run happened and I was introduced to trading. After the bubble popped, I learned how to trade options through TastyTrade [1] and have been doing that since. TastyTrade CEO Tom Sosnoff [2] has a refreshing attitude toward finance that totally spits in the face of Wall Street. I think the way he's addressed and dealt with Wall Street has some clues for how we can similarly criticize the excesses of tech.
For now, getting myself back on my feet has just been the start. I still feel unsatisfied with where I am in life and how I'm interacting with my community and what I can do for others. I have some vague ideas about how to use the money I've raised to bring more awareness to these issues in tech and to support those who are building organizations that address these issues from day one. I don't have anything concrete yet, but I've been trying to network and learn more.
My tech hangover started in 1989. Reading Psychology of Everyday Things and Technolopy helped me articulate my dissatisfaction, transmuted me from a technophile into a humanist.
I started some study groups (for geeks), started volunteering (tree hugger stuff, cancer survivor groups), got very activist / political. (Now experiencing a citizenship hangover. Oof.)
Hanging out with different cohorts is invigorating. Highly recommended.
I wonder about this: how do people archive their information, especially photo and video data. I use an array of mirrored HDDs in different locations with everything on it, plus parts of it on a cloud hosting service. It isn't very convenient though and it seems there should be a better solution. How do people in here do it? Most solutions (for me) fall short on quick retrieval and possibility to visually browse photos.
I buy new hard drives every year and copy all the data to them.
Edit: It's not just the longevity of the drive (though after 20 years they often don't work at all). Drive interfaces change over time, and I have drives where there is no way to hook them up to a newer computer, and my old computers failed due to capacitor problems.
For example, good luck trying to read a 5.25" floppy. You'll need to build your own hardware and write your own device driver to do it.
Just keep copying it all forward every year. Multi-terabyte hard drives are cheap.
The philosophy of just copying data makes sense, but your justification not so much.
> Drive interfaces change over time, and I have drives where there is no way to hook them up to a newer computer
20+ year old PC drives will have IDE interfaces, which you can of course get a USB adaptor for very cheaply and I have several laying about. Really old PCs or non-PC hardware (e.g. the Amstrad CPC 6128 in the 1980s had an after market hard disk option) will need a different adaptor, but it's still just not that hard, and certainly shouldn't be categorised as "there is no way".
> For example, good luck trying to read a 5.25" floppy. You'll need to build your own hardware and write your own device driver to do it.
You can easily buy refurbished 5.25" drives, and you can convert the data signal (which for a PC was basically the same as for 3.5" drives, but with a different physical connector) to USB. They're bulky and they need a lot of power at 12 volts, which is probably why off-the-shelf 5.25" USB floppy drives aren't a thing unlike for 3.5", but it won't require that you "build your own hardware" in any real sense.
You're only going to need to go writing device drivers if you've got some crazy disk format, and it'd have to be pretty crazy because the Catweasel already covered a lot of that territory (a Catweasel was a thing for Amigans, whose disks are a crazy format, to let them use PC disk drives to read their disks years ago, the last ones have an FPGA in them so that the uploadable firmware can decide how to control the drive).
I have several 5.25 drives laying around. The connectors still fit on them to the motherboard, but the BIOS no longer recognizes them, though the BIOS will recognize 3.5 floppy drives.
I can't find any device that connects the drive with the computer that doesn't require writing a device driver.
It's not a crazy disk format, it's DOS format.
As for hard disk drive interfaces, I have a couple off the shelf USB interfaces to IDE drives. The connectors fit, but they don't recognize the older drives.
I can't speak to what's up with the BIOS versus 5.25" drives, beyond to say that I'm confident somebody out there has this working without writing device drivers.
For the USB to IDE thing, my guess would be that the USB interfaces you tried want to do some newer incarnation of ATA than the drive supports and so they can't communicate, at the extreme that could be LBA48 (48-bit logical block addressing, which is from this century and so obviously isn't going to work on say a 20 year old hard disk) but it could even be DMA, which was optional in early ATA specifications and might have been skipped by cheap manufacturers back in the day.
I don't think logical addressing itself was ever optional, but I guess it's possible that a _really_ old IDE drive might not implement it and yet work anyway in DOS which didn't originally use LBA mode. Doing CHS mode really would be asking a lot, compared to PIO (the alternative to DMA) which really a competent implementation of that USB adaptor ought to be able to do, slowly like a real PC.
In the early 80's, I had a PDP-11 with an 8" floppy drive. When I bought an IBM PC, I used Kermit to transfer my files to the PC over the serial cable. Fast forward 30 years, and I had put my PDP-11 Empire game up on github. Someone emailed me that it was missing a file. I was dead in the water, having gotten rid of the 11 long ago.
I recalled my roommate in college might have one. Called him up, he said he was about to discard it, I called him just in time! He said it was unlikely to work (been a long time since it was powered up), and unlikely to be able to read those ancient floppies, but was willing to try.
I had kept the floppies in the attic, and mailed them to him.
They all read perfectly! He sent me all the files on them, and bit images of the disks.
Thank you Shal, and thanks DEC for making machines and floppies that still worked.
> For example, good luck trying to read a 5.25" floppy. You'll need to build your own hardware and write your own device driver to do it.
It's really not that hard, assuming some older PC format. Motherboards up to the 486DX4/120 generation had onboard controllers for the cable to interface to a standard AT type, half height 5.25" drive. I had one in my PC at the time. They read 360KB disks fine too.
From that sort of computer, which can run DOS 6.22, it's not too hard to use it to transfer the data to a modern machine.
> From that sort of computer, which can run DOS 6.22, it's not too hard to use it to transfer the data to a modern machine.
Well, yes, if you have an old computer with 3.5 and 5.25 drives, you can transfer to a 3.5 and read that on a modern computer. The trouble is, my old computers all failed due to capacitor problems.
I can buy a 3.5 floppy usb drive, plug it into any computer, and it works. Not so for 5.25.
> If you mean good luck trying to read a 5.25" disk due to magnetic degradation on the media,that's another problem.
I haven't had much issue with that. About 20 years ago, I transferred my thousand or so floppies one by one to CD ROMs, and later to hard disks. Only a couple were unreadable. I've since found a handful of others, but no way to read them any more.
Processed photos and videos: Google Photos and YouTube. As an insider I know that I can't afford to match the availability of those and having the live display copy indestructible is soooo convenient. Downside: I don't think YouTube will give you back verbatim input material. Photos will, but it can be expensive.
Raw media material after processing: single local HDD and a remote raid.
Home directory: two local time machine HDDs and a remote raid copy of head.
Unpublished code: home directory + a private git server.
Published code: as unpublished + GitHub (which I assume to be indestructible too).
I agree that it's hard to beat the availability of Google consumer services... But that is not backup.
A backup serves as a fallback if for any reason the primary source has become unavailable.
In Google's case such an even can and does occur when your account gets banned because of some random event which you had hardly anything to do with or because your user was compromised.
A backup let's you recover from that and if you don't have that, I hope for your sake you don't mind losing the data too much, because the previous situations happen quite frequently if you actually listen on Twitter, Reddit or whatever social network you frequent.
As I wrote: Google services are the display copy. Conveniently it's overwhelmingly likely to survive for years upon years without any effort. But it can disappear, for reasons you mentioned, in which case I can recover the input media from the options in the second paragraph.
Google Photos is most decidedly not a viable backup for photos and videos.
Google Takeout is broken or flakey, and had been for at least a year. Good luck downloading any archive before it falls with "transfer failed: bad authentication" 30 minutes into the transfer. Of 30 tarballs, only one actually completed successfully. And the images in the tarballs aren't the same bits that I uploaded (via my pixel, so it's supposed to be "original quality," not "high quality").
Pulling your files via the API results in corrupted metadata. Time and GPS location tags are stripped.
YouTube videos are, by design, reencoded with very low bitrates.
I store my important documents, music collection etc. locally on my PC, regularly synced to a NAS, automatically synced to pCloud, and every week I sync to an external hard drive that I keep in my locker at work.
Maybe it's overkill, but it really isn't much work to bring the disk home, fire off an rsync script and bring it to work again the next morning. And external hard drives are ridiculously cheap.
For photos, my phone uploads them to Google Photos automatically. I've been considering moving that to pCloud as well.
Once a year, before christmas, you chose about a hundred of the best photos, print them in a beautiful album, send copies to your grandmothers, and delete the rest.
The problem is that the more photos you made, the more difficult it becomes to pick a hundred. We leave behind so much data trails every day, including data which is no longer relevant. We constantly have to decide which data we keep or 'consume'. The problem is only becoming worse throughout the years (in history). Data is more easily available, and more easily able to be made (or fabricated!) now than 50 years ago.
I've had a policy of keeping one photo a day and discarding the rest for some time now. It's quite freeing to not have to worry about keeping a huge digital archive.
In times where storage space is cheap is there really a difference between keeping one picture safe or keeping 100 safe? If you can keep one safe, you can keep 1000s safe with the same kind of process.
I think there is, my wife's photo archive has 30,000 images. Too big to zip up and put in an email, too big to put on a cheap USB stick, too big to quickly upload to S3, too big to properly catalogue and index, too big to really appreciate.
I was mostly referring to the previous comment about only keeping one picture and not a huge archive.
But I don’t see a problem opening images from 20 years ago. If you are worried just keep a jpeg or raw viewer app in the archive too. Worst case there will probably be emulators to run an ancient OS where your image viewer works and you can convert your images.
I have a small laptop running a few services for home use, incl. a DLNA server and network storage. Media dropped on a specific network drive will be available over DLNA.
Makes it easy to look at photos from computers and DLNA capable TV's, but it doesn't work for archival purposes as the laptop used as a server isn't really redundant.
Our own laptops are backed up using a cloud backup solution.
It would be neat to have a service that converts digital photos to the equivalent of film or microfilm, an analog medium that can be converted back to full size pictures in a hundred years. It would have to be scalable and cheap though, given how easy it is to take pictures nowadays.
But yeah, spend $100 / year and get a big film roll of your photo archive, that would be neat.
A few of my co-workers have cross-site backups arranged with siblings or parents. Each house runs a few local servers and mirrors the backups to the other house.
This relies on having a trusted party outside of your natural disasters zone, but it's pretty cost effective if both parties wanted to run home servers anyway (e.g. Plex, homelab)
I recently stumbled upon the word 'lakh' in the Indian number system meaning 100000 [1]
, which according to Paul Thieme [2] may be related to the German word Lachs, for salmon, referring to the innumerable fish in a swarm.
The way languages are connected in their histories while seeming so disparate today keeps fascinating me.
“That is total political crap,” Cook fired back. He said he’d “love to bring it home” but doesn’t because “it would cost me 40%... and I don’t think that’s a reasonable thing to do. This is a tax code, Charlie, that was made for the industrial age, not the digital age. It’s backwards. It’s awful for America. It should have been fixed many years ago. It’s past time to get it done.”
I'm a little insulted by the fact that Cook thinks it's up to him to decide whether or not his company should be paying taxes. Obviously they've found a loophole, but his phrasing suggests he's doing it for the greater good. Maybe if Apple and similar huge companies actually paid those 40% (I doubt it's that high a percentage) to government, public school could get more funding, etc. and the US wouldn't need as much philanthropy.
Insulted?
Apple paid taxes on foreign earnings by foreign branches in the countries where earnings occurred. What nonsense is being dismissed is the idea of then paying duplicate income taxes, on the same earnings, to a second foreign government: in this case the United States. It's obscene to think it makes sense. The fallacy in perception is a political slight of hand to fury fund a way too hungry big government many would say.
Apple US sells Apple Ireland a macbook pro for 1000$. 1000$ is what it costs Apple US to get it from China, so no taxes as there is no profit.
Apple Ireland sells that same macbook to Apple UK for 2000$. Apple Ireland realizes 1000$ in profit, and pays the Irish rate on that profit. Apple UK pays no tax, because they bought the machine for 2k and sold it to consumers for 2k, giving them 0 profit on the sale of a new macbook.
Using this shell game i can realize 100% of my profits in any particular tax jurisdiction that I want; regardless of where sales are actually made.
I now pay 0 taxes in the UK regardless of whether I sell 1 unit or 1 billion units in the UK.
Do you think this is above board?
Do you believe that the company selling 1 billion units and paying 0 taxes represents an equivalent burden on society to the company selling 1 unit and paying 0 tax?
Does this company not use the publicly maintained roads? Airports? Are its UK workers not kept healthy by the publicly available health services?
Sure apple paid all of its legal obligations on its 0$ of profit in the UK - how they ended up with a reported 0$ profit in the UK is something worth having a conversation about.
No they don't - in Europe they managed to cut a deal with Ireland such that only their Irish generated revenue was taxed in Irleand but all other European revenue was booked against their Ireland business so was completely untaxed
Apple have not just followed the law as written - they have carved out specific tax exemptions for themselves.
The sentence means that Apple haven't simply / only / just followed the law as written, they have gone further than that and carved out specific exemptions in the law for themselves.
When you said, "I think they have followed the law as written." it sounds like you are challenging a claim that they haven't followed the law as written, but that wasn't the intent of the sentence. More clear? No laws were violated.
A) I have not hit you, I have given you a hug.
-> you did not get hit, you got a hug
B) I have not just hit you, I have given you a hug.
-> you got hit AND you got a hug
That's not correct. Apple do not pay income tax here in Norway even though they obviously sell a lot through the Apple Store. They "pay" tax in Ireland, which I assume is next to nothing. The argument is not about paying duplicate income taxes. It is about Apple and others using loopholes to get income in countries with low/zero tax rate instead of the country they sell in or actually operate in.
"Apple do not pay income tax here in Norway even though they obviously sell a lot through the Apple Store."
Corporation taxes are levied on income, i.e. profit. Yes, Apple sells a lot through the Apple Store in Norway, but do those stores make any profit?
The retail margins on Apple products are tiny. Try negotiating a discount on an iPhone from an Apple reseller. Would the Apple Store (which probably has a much higher cost base than a normal Apple reseller) make any profit? If not, why should they pay corporation tax?
> Would the Apple Store (which probably has a much higher cost base than a normal Apple reseller) make any profit? If not, why should they pay corporation tax?
Is the App Store based in Norway? If not, why would it be subject to corporation taxes in Norway? Just because it has customers in Norway? Would you expect a SaaS provider in Norway to pay corporation taxes in the US just because it has customers there?
This is exactly what the discussion regarding digital sales is about. Apple has set up their store in Ireland even though it is an American company. They have people employed in Norway and sell to Norwegian customers but pay no taxes as sales are made through Ireland.
I expect that a company pay taxes where they realistically operate. I don't think it's fair to set up shell companies in countries where they have no real operations. A company uses a lot of state resources that are paid through taxes. Without contributing they are cheating the rest of the people in a country.
"I expect that a company pay taxes where they realistically operate."
Would you expect a SaaS provider in Norway to pay corporation taxes (i.e. a tax on company profits) in the US just because it has customers there?
What about state and federal sales taxes?
Would your answer change if the company were to have a single marketing employee based in the US?
What if none of the company's customers are in Norway, but all are in the US? Should the company pay profits taxes in Norway, the US, both, or neither?
To say it is a loophole makes it sound like only a few use it or that it's some obscure detail that allows for this. As far as I know, this applies to every foreign company and is very clear from tax law.
It's quite a deliberate international network of companies purely set up for the purpose of not paying tax. I would say it's a loophole even though it also consists of obviously legal and locally encouraged practices such as setting up a company in Ireland with a low tax rate. But yes it's an issue with lack of international agreements to avoid situations like this with huge corporations not paying tax locally and small businesses in the same area paying high local taxes.
Do you really think Apple makes the majority of their income in Ireland? On paper they do, if you follow the twisted winding path of tax codes from the United States through Denmark to Ireland.
Yes, Apple and any number of other companies have all cleverly discovered the sneaky loophole that was created unintentionally and has been left open purely by oversight for lo, these many years.
If the loophole wasn't created at the behest of lobbyists, it's been kept open and/or widened by lobbyists. Whether or not Apple itself had anything else to do with that, it's part of the playing field now and it would be corporate malpractice not to use it. The way for a company to help fix this problem is not to become less competitive on principle, but to use their lobbying power to adjust the whole playing field.
To me, it's no different than me buying raw ground beef (not taxable to me locally) vs a prepared hamburger (taxable to me at 7% locally).
I'm free to choose between those, but when I buy raw ground beef, I'm not evading taxes and I assume you don't feel insulted by the fact that I think it's up to me whether or not I pay beef tax.
It's a choice I make in the face of a multi-dimensional optimization problem, same as Apple is doing on a scale 10^9 larger.
I'm also using a very simple example to talk about making specific choices on which legal action to take in the face of varying tax incentives, which is analogous (though not identical) to the choices multinationals face when deciding whether to do X, Y, or Z.
(where X might be "do foo in one jurisdiction" and Y might be "do foo in another jurisdiction" and Z might be "do bar instead")
> I'm a little insulted by the fact that Cook thinks it's up to him to decide whether or not his company should be paying taxes
This is not that uncommon among affluent people to think that they shouldn't pay taxes,in fact they have the money to set up schemes in order to not pay any.
That's naive: they did pay taxes already, on earnings in the countries of the earnings, and are saying that, for example, the Brazilian company Apple Brazil, paid up on Brazilian income tax for work done by Brazilians in Brazil, should not then pay 40% more to the United States for work done in Brazil.
It's not about paying 40% more -- tax already paid to foreign governments is deducted. So the total tax is 40%, with any tax not paid to foreign governments going to the US government when the profit is repatriated.
Per wiki, 35% + up to 12% of State/Local income tax; less any foreign tax already paid (as tax credit); less any other deductions and credits. Per http://www.politifact.com/punditfact/statements/2014/sep/09/..., the reality is more nuanced. The World Bank and International Finance Commission puts the United States’ effective rate for 2014 at 27.9 percent.
It should be noted that value-added-taxes (VAT) seem to go from about 10 to 20 percent. The US doesn't do VAT; it's largely state and local sales taxes where applicable, generally less than 10 percent.
The US has one of the worst if not worst tax codes in the world and especially for business. Plus the simple fact remains, businesses only collect taxes, if they have not sent them in then all they have done is not sent the money every supplier, customer, employee, and shareholder, has paid as a tax.
Indirect taxes are the big slight of hand that all governments use to keep their people from knowing just how large of a tax burden they truly have. The US went further with withholding taxes.
Yeah, morality aside, it's very interesting to think about all of the taxes that Apple has already paid in various countries: sales taxes (and/or VAT), payroll taxes, income taxes for their employees, property taxes. (And that excludes things like health care plans, pension plans, etc.)
Talk to your government, vote, make things happen. Thats up to you. If the government established a law, Apple and others would pay or course. On the other hand, if compaies paid more then required, management would be sued by shareholders to oblivion. Want to change that too? Vote, make things happen.
What specifically is he talking about here? If we're talking about manufacturing, a tax code for the "industrial age" seems about right. If it's about digital content distribution (itunes etc.), okay, but what works for steam engines but not for laptops?
Projects like this are so fascinating to me. I saw an art piece once that consisted of a TV that rotated through all possible pixel combinations. Think about that for a second: at some point in time, it will display any possible image anyone could ever make or dream of (in that given format). Any person's face, any movie-frame, any written sentence, etc. So fascinating, the vastness of it all.
Most likely most of those images are just random noise, and nothing intelligible. It would take longer than the heat death of the universe for that TV to display all possible images.
Let's examine an extreme underestimate to demonstrate this.
Say the TV is monochrome with an 8x8 resolution, and it can change it's image every millisecond (1000 fps). It would then take 2^(8*8)/1000/3600/24/365 = 584,942,417 years for that TV to generate all possible 8x8 monochromatic images.
Then when you consider that the TV is likely running at something more like 640x480 resolution with 24-bit color at 60 fps, you can see that it will take an astronomically larger amount of time for the actual TV to display all possible images. The time would be larger still if the TV were running at 1920x1080 resolution (or 4k!).
Further more, a large majority of the sample space is just unintelligible noise, and the vast minority of the space is actual recognizable images. So likely, the art project will just be displaying noise until the end of the human race.
I don't think this takes anything away from the artistic merit of the work, it just changes the message a little. We humans are capable of creating a machine that can display every image, but we will never be able to see them all. It is an interesting contrast between the creation of a generator and the execution of it. I don't think this is what the artist initially intended with their work, but it is interesting to ponder nonetheless.
I'm missing some definitions here. Not sure if I didn't see something, but what are they assuming in terms of number of hours/week and what does "two-bedroom housing wage" mean: is this just the wage at x hours/week that allows you to rent the average 2BR or does it include some other kind of spending like food? Because what does it help if minimum wage pays for the apartment but I can't eat?
On a different note, in relation to everyone asking why 2BR is important: please just imagine being a single parent with, say, 1-2 kids and a minimum wage job.
They're looking at how many hours worked at minimum wage that it would take to afford an average priced 2 bedroom apartment, if you only spend 30% of your income of housing.
Wow, how can something like this happen? I thought airplanes had triple redundant software systems using 3-version programming [1] in order to avoid such bugs/problems. Can anyone familiar with flight technology shed some light on this?
Not an airplane programmer, but I seem to remember that the literature says that it's not generally a cost-effective way of finding bugs. In particular, you multiply the cost of development by (say) 3x (which is fine, on its own) but also the places where bugs are inserted are typically the hard parts; so you don't reduce the number of bugs as much as you'd like; it can easily be more cost effective to invest the few million in static analysis etc.
As much as we'd like plane manufacturers to test things to death, it'd become too expensive too quickly. For all we know, this software could be written by a contractor, or the firmware for a third party part.
As far as I know, N-version programming was effective when software systems were small (shuttle ran on 50k lines of code) and where poring over every single line was possible, because the hard part was coming up with the spec.
Nowadays a big plane like the A380 might be expected to have 100M lines of code in its subsystems, and it's simply too expensive.
Sorry if this is incredibly ignorant, but I can't believe flight control systems are running Linux?
Do these systems not have hard real-time requirements about the execution time and periodicity of tasks which can't be guaranteed by the time-sharing scheduling algorithms in Linux?
Real time systems will be running a RTOS: VxWorks or QnX or something equivalent to that.
They'll definitely build a prototype using Linux but they won't get that certified so it literally 'won't fly', it's just a means to speed up initial development.
Wow, I had no idea. Since their source is closed and untouchable I had no way to check either. Is there any reason there aren't several certified open RTOSes around?
I don't know if there aren't any open certified RTOS's around, but I can explain the 'why' part easily: if you pay for the certification of an open RTOS then everybody that can use one will say 'thank you' for the effort and that's that, since the certification would apply to any and all copies of that particular version. So you're essentially paying for the privilege of cutting your competitors a break.
This could only work if the entity paying for the certification had a way of making that money back somehow and I don't see how that could be done.
Not to detract from the fine work done by the sel4 folks, but there is a large gap between what they have and what DO178 C requires for level A software. Like many other bureaucratic organisations, the FAA (and other regional equivalents) have a process with it's own set of rules (MCDC testing, requirements/design traceability artifacts, etc).
It would cost a significant amount of money to develop the necessary artifacts and engage the FAA to obtain a certification.
That's absolutely true but something like this could be a good starting point.
What I think the whole thread above misses is that the economics simply aren't there, cost isn't the limiting factor for the OS licenses for avionics but an extra certification track (especially for a fast moving target) would be, besides, it is not just the OS that gets certified but you will also have to (separately) certify (usually) the hardware that it runs on (unless you're going to use a design that has already been certified).
That means that modifications are expensive and that 'known to be good' trumps 'could be better' or 'could be cheaper in the longer term'.
Someone would have to come up with a very good reason to see open source trump the existing closed source solutions.
In theory, while certification would be done on a binary derived from seL4, any improvements resulting from the certification process could benefit the open-source core and derivative binaries. Compared to a proprietary OS, improvements would have ecosystem-wide benefits.
In addition, a modular microkernel architecture could use reproducible builds to generate identical binaries from identical source. This would enable binary components to be certified both separately (akin to unit testing) and as an integrated system (mix and match components). This could reduce overall duplication and certification costs, even among competing commercial products derived from seL4 components.
There are - to my knowledge, feel free to correct me - no real time linux versions (or even any version of linux) that are currently certified for avionics (DO-178B certification is required for that, there are multiple levels and I don't know of any linux distro (or just the kernel) with that certification).
Avionics certifications are well past the extent of my knowledge and I will gladly accept your point. I was generally addressing the idea that the need for preemptive scheduling precludes the use of a Linux-like kernel.
I've never heard of anyone getting Linux running under hard real time constraints. You can get it pretty good (excellent for real time audio, for example), but can never be 100% sure you're going to meet the deadline. The people I've talked to who tried said by the time you strip out enough of the kernel to approach hard real time, you've lost enough of the advantage of using Linux that you may as well switch to an RTOS.
Real time audio only if you use a large enough buffer and a hardware component to clock the data out.
It's all about the latency guarantees and that means that you're going to have to inspect each and every path through the code for length. With the complexity of the linux kernel that's a pretty tough job and I suspect that anything lower than a few hundred milliseconds (guaranteed!) is out of the question.
I built a little controller using linux that required hard real time during a long (multiple minutes) of operation and the way I hacked it was to simply disable all interrupts and recover the various drivers as good as possible once that phase was over. It worked well but was mostly deaf to input during that time except for polling one 'stop' switch which would cause the machinery to coast down to a halt after which interrupts would be enabled.
Good enough for tinkering but I certainly would not bet anything in production on that strategy.
Real time is hard, soft real time is hard enough (without guarantees but with a best effort and a very large fraction of the deadlines satisfied), hard real time (no misses at all, guaranteed) is hard for a kernel of any complexity.
A complicating factor is that you really should include your compiler as part of your codebase (if you're doing lots of formal method work, you will usually do it on the source code, and the compiler can invalidate all of the guarantees you carefully program in), and this will be millions of lines of code (where you can't simply factor a tonne out).
it's always easy when you're not the one making the changes on the system you don't understand. is there a name for that? I feel like it's a common enough thing people do that it should have a catchy name.
Eh. To say that something that used to be mechanical should be possible with a mere few million lines of code seems pretty obvious to me.
Or compare to the Apollo missions and the space shuttle being well under a million.
I'm not saying that it would be easy to redo the entire system from scratch now, I'm just saying that if it was a design goal from the start it wouldn't have been very onerous.
Because each discrete component that you can eliminate (and replace with code) is a weight saving. Because once you tip over a point in complexity, you just keep adding more code to guard against more edge cases - edge cases you can't avoid because they involve crashing into mountains. Because you want to offload as much possible effort from the cockpit crew, while still allowing them full control over the automated feature
The complexity of the software that manages the N versions seems terrifying, and decision-by-committee in the implementation seems problematic. 3 implementations could select different sequences of responses to a situation, each of which individually is correct, but which are disastrous when combined by vote. E.g. say they're voting on 3 different numbers that have to add to 1; proposals are (1 0 0) (0 1 0) (0 0 1). Consensus is (0 0 0), oops there goes a billion kilowatt dam.
I'm not exactly an expert on search machine technology, so I'd be grateful if someone was so kind to help me out here:
I did a "conversational search" asking "what's an amazing voice" and Google returned a definition with a Youtube video of a woman singing. One of the comments simply says: "Amazing voice!"
Why is this listed as a definition? What's happening here?
In your other point though, I‘ve seen highly effective managers who didn‘t understand much of what the team was doing technically, because the were able to build trust among everyone involved in major processes.