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Comment by StillBored | Hacker News Reader

How do you know that? Filesystem corruption is frequently silent, and every-time it happens customers don't get on the phone and send the disks to apple so that they can root cause the problem. Its quite possible this bug has happened an untold number of times before it happened to someone who went through the effort to reproduce and isolate it.

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Also, I'd guess the use pattern on ios is rather different, and more homogeneous, from the use pattern in macos. I don't think these millions of devices really give Apple good code coverage.

>How do you know that?

Can you point to any other APFS issues that were reported before this one?

My wife's laptop suddenly decided that the boot drive was corrupt a few weeks after she updated to APFS. None of the recovery tools were of any use. We had to reinstall the OS and pull the files from a backup. This story did not make it to Hacker News.

I thought Diskwarrior supported APFS - did you try that one?

Anecdata != filesystem issue.

If you have more information about the problem you encountered and how it implicates/interacts with APFS, please do link to it. Otherwise, bug reports via circumstantial evidence are, while not inherently false, certainly suspect.

You missed the point. The anecdote was to illustrate how even power users might be working around filesystem bugs so a lack of bug reports specifically mentioning APFS is certainly not proof that there aren't problems.

It's also quite hard to report fs issues. I ended up one day with a not working apfs system. Boot was ok, but I couldn't mount the user partition. Apfs repair tool just failed and made the system hang. After a number of restarts, attempts at repair, and attempts to move the partion somewhere it can be decrypted, everything started working. And I actually had enough experience to try and debug/fix it - many people would end up wiping the system, or having to go to Apple shop.

This is not reportable. I got only a generic error or hanging system. I can't reproduce it. I don't know why it started and why it finished. Yet, it was almost certainly an apfs issue.

Even if I wanted to play, my priority was to get the work laptop usable again.

That's reasonable. I assumed that it was an assertion of evidence of an issue, not an example of how issues might theoretically go unnoticed. Upon rereading it does not appear that either is implied.

I'm not sure they're implying that it -was- an APFS issue, just that in the majority of circumstances users won't go through the same level as effort to diagnose an issue as in the article. Instead of pulling drives and trying to reproduce the error, they just wiped the drive and started fresh.

I could be wrong, but I believe the point is not that it did happen, but that this -could- have happened many times in the past and users just format/re-install without thinking about it.

The hardware is likely being blamed for a lot of failures that are software related. Its almost assured there is a software problem in cases where reinstalling the machine fixes the problem. A random machine which won't boot due to disk/filesystem failures could be a hardware issue, but that is pretty much ruled out if reinstalling/reformatting doesn't immediately manifest in further failure. Bit rot, stuck bits, bad links are a thing, but they generally show up as massive soft error correction long before it reaches the point of simply being unable to read the sector and when that happens the OS will almost always tell you that the sector can't be read rather than giving you garbage data.

That is because the likelyhood of undetected hardware failures given the layers and layers of ECC on the disks, links/etc manifesting itself as filesystem meta data failures rather than garbage in the middle of video/images/document streams/etc is really unlikely. Or the more likely case of the machine performance degrading due to read retry/ecc correction/retransmission making the machine appear to have severe performance issues long before it manifests as silent data corruption sufficient to eat the filesystem structure (its a fun excise to intentionally flip a few random bits on a hard-drive image (or in RAM)) and see if/when they are detected.

So, yes the first thing I think when I hear filesystem corruption is BUG! That is what the experience of tracking down a number of incidents in a large data storage application a few years ago taught me.

You asked for an example, and you got it.

You're confusing your posters. freehunter asked for an example. zbentley complained that it was anecdata/specious.

I have an iPhone 6+ that's stuck in an infinite boot loop. Everyone thinks it's a BGA solder ball failure on the NAND flash part.

Can you be 100% sure it's not an APFS fuckup?

to be fair, BGA solder joint issues are ridiculously common on that model. to the point that, as someone who's services phones for years, i warn people away from them even if they're dirt cheap

The rest of the post after the question mark you stopped reading at:

> Filesystem corruption is frequently silent, and every-time it happens customers don't get on the phone and send the disks to apple so that they can root cause the problem. Its quite possible this bug has happened an untold number of times before it happened to someone who went through the effort to reproduce and isolate it.

We know that because it was deployed to almost a billion devices without a problem. If there was a problem that affected even a fraction of a percent of people, it would have been all over the news given how many devices that is.

Edit: Thanks for the downvotes. If you disagree, please tell me why. Apple's deployment of APFS to iPhones was so flawless, most people probably still don't even know they did it.

Idk, most of the people in my life could probably lose data on their phone and never realize it. Especially if we’re talking about people with lots of duplicates of the same selfie, for instance.

The downvotes will be because you're adding nothing to the conversation. You're just repeating your grandparent post's point.

You’re wrong. I’m explaining why deploying to a billion devices and seeing no public outcry means there was a problem, because the parent comment is trying to claim that maybe there was a problem and people just didn’t report it. My point is that with a billion devices, even rare edge cases end up reported in the media because rare edge cares still hit so many people that it makes it look like a widespread issue.

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