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Comment by grahamm | Hacker News Reader

I think people forget what it was designed for. It was to reboot IT education which was (is) badly floundering. It's success was so good it started to be used in small commercial applications. The Foundation tried to help fill this gap in the market with the compute module. Even though there is a lot of open source features the use of the Broadcom chipset was probably driven by cost as keeping the Pi price down was a factor. If a fully open source and open document solution is required perhaps the Pi isn't the right choice but then that was never it's original goal.

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It's the standard pattern where someone comes along and says "hey, we made this thing which does X pretty well for a good price". Then someone else comes along and say "we wanted to use it for Y, but it's not good at that, therefore the thing itself is bad, and it's creators should have focused on making it good at Y instead".

AFAIK, Raspberry Pi was, among other goals, was designed to help poor students learn software and hardware. I am not sure how one can do this with such a huge proprietary blob.

I’m tired of pointing this out. The reply is consistently “So what? It’s my cheap Linux SBC now and until you can find something better for $40, go away.”

I‘be been booting off of eMMC on an A7 for years now. I don’t get any of this anymore.

It has a huge support community that is very friendly, that's as valuable as anything.

I too, am tired of giving that reply - I don't know why the issue must be continually raised on every Pi article; it's a little patronizing ("Oh, those poor Pi users don't know any better"), and that grates when you have researched and ended up with the Pi as the best-fit.

Both things are true - yes the Pi is not the most robust SBC on the market, but the Pi also offers the best value for money hobbyists and tinkerers. You (generalized) and I have completely different priorities and we will accept very different trade-offs: price is important to me - reliability, not as much. I would rather drop $40 on an SBC that may or may not kill my $5-$15 SD card in the next few months than spend >$100 on a rock-solid eMMC-/CF-based one. Most of Pi users are hobbyists who are not running critical code, if it fails they will fix it next weekend. Maybe.

If the pros fail to understand that the needs of hobbyists are different, then this back-and-forth will never cease.

I don’t even address hobbyists. Let them do what they want.

I’m taking about the people I encounter that are trying to use an RPi as an off-the-shelf compute solution for a production device.

I'm always amused and simultaneously annoyed by those ads about Raspberry Pi "killers" that are X amount faster or whatever, but they never get around to pointing out the price factor. They nearly always start at double the price. I'd only expect them to outperform the Raspberry Pi if they are double the price.

The Raspberry Pi is what it is, and is in every way brilliant for it. If you want X amount faster, you pay for that. That's not a Raspberry Pi killer. It's a different category altogether. Those SBCs cost more, and therefore you get more. If you need that, Raspberry Pi isn't what you need. But if you are within the group that Raspberry Pi caters to, it's hard to find better.

It's like saying the new electric Harley Davidson motorcycle is an e-bike killer. Of course it's faster and more powerful and has more this and that more features. It costs more. It's just not the same thing.

PS: The new Rpi 4 with lots of RAM is certainly getting there. I actually use one as my desktop even though I have far more powerful equipment in my studio.

I can't imagine having to sysadmin a bunch of raspberry pis in a serious "production" setting with all the reliability problems they have, that would be godawful, you'd go through a brace of SD cards every month

Why? I supported 40 of them (rpi 3) as remote serial hosts and custom reboot/repower for a QA farm. Not a single one failed and don't think I had a single issue during that whole time. As far as I know it's still going just fine. It was a cheap and dependable solution. 99% of the SD card issues go away when you don't cheap out and don't go cheap. get a large card that is 32GB plus from a respectable vendor. That's not the rpi's fault on the failures, it's the cheap ass SD cards that people buy.

It is the fault of Pi hardware when it still refuses to provide a hardware shutdown button for proper file system unmounts, after all these years.

Dependence on SD Cards and lack of orderly shutdown was what caused my company to not go with the Raspberry Pi. Even then we have back up power to allow the system time to shutdown.

Considering it was designed for IT teaching and not for embedded use, I cannot fathom why your company and many others contemplate using it in such a capacity.

Machines no longer degrade when the power is yanked. Any corruption caused by a mid-write devoltage event is handled gracefully by whatever modern filesystem of choice you are using, is it not?

Is there some more fundamental hardware damage that occurs when USB devices are unplugged without prior warning to the device itself?

It does, when your crappy hardware doesn't lie to the kernel. Go take a look at the amount of unrecoverable FS corruption discussions at LKML. It still happens relatively frequently, and is almost always caused by shitty hardware ignoring fsync and lying to the filesystem. SD cards and cheap SSDs are especially terrible in this regard (that's why I refuse to buy anything except from the most respected vendors, and they still have their issues). Many devices don't even report checksum mismatches on read requests and simply return garbage data, and most filesystems don't notice it (because they don't implement a data integrity checking mechanism of their own)

Because of large erase blocks, it's unavoidable that a flash device needs to involve some kind of very careful bookkeeping and sector-shifting to safely handle power loss during writes. Otherwise it could lose a big chunk of sectors unrelated to what you were actually writing, and that's not something a filesystem can paper over. I barely trust a proper SSD controller to do this, let alone whatever cheap thing is in an SD card or flash drive.

1. A modern filesystem will stop the filesystem getting corrupted by power loss - but a file that was mid-write, or an install process that had copied half the files it needed to, will still leave that thing incomplete.

2. SD cards can wear out (i.e. too many write-erase cycles) regardless of the filesystem.

3. SD cards have controllers running firmware, doing things like write levelling and bad block remapping. Some cards have bugs, and if the card is lying to the OS about a write completing, or if the remapping table is less resilient than the filesystem's journaling, you get problems even if the OS and everything on it is perfect.

4. Problems like pins with poor connections and power supplies not providing enough current are exacerbated, as microsds have no space for power capacitors and few SD card holders are rated for hundreds of insertion cycles.

5. SD cards start out a lot cheaper than SSDs (easier to find a sub-$10 SD card than a sub-$50 SSD) and the market is awash in fakes

All these problems look very similar - "My RPi stopped booting, I replaced the SD card with a freshly written one and it started booting again" - making forum anecdotes and user bug reports hard to rely on.

I just spent $10k on 4 Siemens 32Gig industrial SD cards for S7-1500 PLC's, in safety service.

Gauranteed 500,000 writes, probably much more, but they have "mission life" quoted at ten years on the vendor cert, so will be ditched after ten years and replaced.

Apparently they are a whole different type of logic design, hence the cost. Even the no-name or branded equivelent I could find were close to $1k each, but given use in safety service we went legit all the way anyway.

Anything with the magic S word stamped on it seems to double in price...

Lots of points you make are true. Yes, if you yank the plug without saving you lose your work. Or Exim will have to flush the queue again. Or vim will have a dangling swapfile that it will ask you about next time. Or you’ll have to start over on your game of solitaire.

And yes, SD cards have flaws.

My question was: if I turn my computer off every day by yanking the power cord, I expect nothing to break, so what am I missing when people seem so wary of doing it?

(Recall that this was all in the context of a parent comment lamenting a lack of a dedicated shutdown button on the RPi.)

With the number of GPIO pins available - you could always wire-up one yourself if a physical button is important to you.

That said, I don't think the Pi was ever designed for "serious" industrial usage; I don't think the production runs (or the foundation) could support that, without undoing the core mission.

I can talk to managing Pis in an educational setting, and honestly, it is less bad than expected. (Disclaimer: No longer a school sysadmin. But was for a number of years.)

First some comparisons. Kids are seriously rough on technology. We had a fleet of about three hundred laptops, two hundred iPads, and two hundred Pis in the junior school.

In a year, we'd end up with about a hundred laptop screen replacements, two hundred keyboard replacements and about a hundred hard drive replacements. About ten "I accidentally dropped the laptop in the river"s. We'd cycle the laptop out for a brand new one at four years, if it survived.

In the same year, about sixty iPad screen replacements, ten or so battery replacements, and twenty or so river dunkings. Only ever had one hard drive failure, apart from water damage, but the iPads were on a short two-year upgrade cycle.

The Pis were used for the robotics clubs (optional) and programming (compulsary). Pis aren't great for kids and robotics due to lack of protection on the pins for dumb mistakes. We had about twenty fizzle the mysterious smoke every year. About twenty more than experienced SD card failure in the year, usually related to yanking a power cord, not direct write failure. We also had a couple students a year who snapped theirs in half.

All in all, the cost of maintaining the Pi fleet was negligible besides the rest.

I've snapped/bent a few microSD cards myself trying to remove them from "exotic" cases, both times in hasty situations (interactive art shows). I've learned to slowly remove them while not exerting any vertical pressure when it's still halfway inside the Pi - just keep trying to slide the card out while using fingernails to catch the bump on the end.

Ah, sorry. When I said "kids snapped theirs in half", I wasn't referring to the SD card. I was referring to the Pi itself. Kids can be monstrous when it comes to technology.

How on earth do you get a “hard-drive failure” on an iPad?!

By sitting the iPad in the mysterious gunk that lies at the bottom of a kid's backpack. After stewing for a few weeks in exotic biological material the internals can begin to break down.

The cases are sealed, but they're still permeable to stuff you wouldn't let near your computer because you have a slight respect for technology.

I found fungus growing inside more than one iPad case, usually directly in the boards.

The iPad doesn’t have a hard drive. It has flash storage. The term “hard drive” is not a synonym for on-device storage: hard drives were a prevalent form of storage, but let’s not become so lax with terminology that it no longer means anything...

Yes, the iPad has flash storage. The same specific kind of flash storage that you'll find inside an SSD. And SSDs are typically referred to as hard drives.

The semantics on this one aren't worth exploring.

If you avoid the extremely common mistake of mounting the SD card RW instead of RO then Pi problems are negligible.

Raspberry Pis are actually very reliable if you don't use the cheapest possible power supply and SD card from Amazon. I have several that have years of uptime.

That said, I agree kids are rough on any technology.

Actually the problem is with unexpected shutdowns so logically if you’re having years of uptime you wouldn’t be seeing these issues.

No doubt, RPi has been a boon to the world and the popularity speaks for itself.

How exactly does it help IT education and what was wrong with it that it needed a "reboot"?

The original idea was giving kids a device they could just connect into a TV (no need to buy a new screen) and learn by screwing up like ~"we all did when computers were simpler."

iPads, iPhones, Windows, etc.

They're expensive and complicated. Kids can't take the family computer and screw up installing linux 3 times while Mom needs to do something for work. A $25 computer is something a family could easily afford and so could school districts.

We had computers at school, but we didn't have great teachers. Wouldn't be better if school spent money on good specialists willing to share their knowledge or at least make sure kids watch certain channels on YouTube that have wealth of knowledge? If parents won't spend $200 on a computer to help their children get better future, their certainly won't spend $25. I bet they wouldn't even treat this seriously.

Most kids only experience computers through a smart phone and a collection of social media apps.

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