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MacOS may lose data on APFS-formatted disk images

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Re: MacOS may lose data on APFS-formatted disk images

#171

Earlier quoted context omitted.

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.

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.

Re: MacOS may lose data on APFS-formatted disk images

#172
post #150

Earlier quoted context omitted.

Also, nobody is harder on Apple than the people who know the company best. He’d lose credibility if he pretended everything was all rainbows and unicorns when they clearly are not. He clearly cites how unacceptable some of these bugs are—that’s not being biased. Like Ritchie, I go back to the days of when the Macintosh Operating System shipped on floppies and didn’t have pre-emptive multitasking or memory protection—…

So we now measure the reliability of a consumer-grade system on closed hardware by how few times it experiences a kernel panic ? That’s a very low bar. At least Windows has the excuse of having to work with a bazillion drivers.

I am not sure what your point is. If macOS has fewer kernel panics on semi-closed hardware (what laptop/PC hardware is more open these days?) than Windows or Linux on a bazillion drivers, then macOS would be preferable to me if the hardware us acceptable, even if supporting a bazillion drivers is a greater feat.

Re: MacOS may lose data on APFS-formatted disk images

#173
post #42

My AFPS volume got corrupted probably during the upgrade to High Sierra. No data lost, but my disk is missing almost half the disk space. See https://apple.stackexchange.com/q/311843/26185

I “lost” a lot of space due to time machine local backups. It was frustrating to research and I thought there was something seriously wrong with my computer. Try deleting the local backups and see if you get some space back

unfortunately it's not the local backups. I guess the missing disk space is related to the error I get when I check the partition. I guess I need to reinstall... :(

Re: MacOS may lose data on APFS-formatted disk images

#174
post #86

Earlier quoted context omitted.

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.

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.

Re: MacOS may lose data on APFS-formatted disk images

#175
post #96
post #39

I tend to create sparsebundles to clone my git repos within, to get around the overhead of having huge numbers of inodes on a volume. (Copying, deleting, unpacking archives, Spotlight indexing—all are way slower when you have the worktrees and .git directories from a thousand large repos splayed out across your disk.) So I was a little worried here. Thankfully, I had manually been setting my sparsebundles back to HFS…

Well, APFS is much better suited to this kind of workflow. Create a space shared logical volume inside your container and turn spotlight off on that particular volume (and if you’d like, make that volume case sensitive ). There’s no need to separate that out on a diskimage

There's still the problem of Time Machine (or any other backup software you use) needing to do a complete deep scan of the volume to ensure you haven't made any changes. If you know a git repo is effectively in a "read-only" state—something you just keep around for reference, or an old project you might "get back to" a few years from now—it can speed up those backups dramatically to put the repo into some kind of archive. Disk images, for this use-case, are just archives you can mount :)

Re: MacOS may lose data on APFS-formatted disk images

#177
post #150

Earlier quoted context omitted.

So we now measure the reliability of a consumer-grade system on closed hardware by how few times it experiences a kernel panic ? That’s a very low bar. At least Windows has the excuse of having to work with a bazillion drivers.

I am not sure what your point is. If macOS has fewer kernel panics on semi-closed hardware (what laptop/PC hardware is more open these days?) than Windows or Linux on a bazillion drivers, then macOS would be preferable to me if the hardware us acceptable, even if supporting a bazillion drivers is a greater feat.

The point is that Apple provides both OS and drivers for a relatively small set of hardware. In these conditions, the fact that it has kernel panics at all is just Bad. Kernel panics should not happen in 2018, we have the knowledge and the technology to make it happen. It's bad for Windows and Linux as well, but they have the drivers excuse at least - MacOS has no such excuse.

Re: MacOS may lose data on APFS-formatted disk images

#178
post #166

Earlier quoted context omitted.

ReFS was only ever made the default on new installs of Windows Server 2012. It never actually made it to production builds of Windows 8 or above so it's actually only installed on a fraction of the systems that are out there. That's not really a sufficient sampling size to say that this deployment went along much better. The APFS update was a much, much larger endeavor and, based only on public response, was nearly s…

yes, huge deploy but not that seamless. 1. i had a filevault related corruption issue, the disk was eating itself up thinking it was encrypting... don't have the apple discussion link at hand. 2. time machine hidden snapshot, "disk full" issues. it's a major pita for me that is not possible to turn off local snapshots.

it's a major pita for me that is not possible to turn off local snapshots.

Try this terminal command:

   sudo tmutil disablelocal
Edit: I'm still on Sierra. Someone else mentioned that HS removed that. But also pointed to: https://forums.macrumors.com/threads/solution-reclaim-storag...

Good luck!

Re: MacOS may lose data on APFS-formatted disk images

#179

APFS not having block or file-level checksums really seems like a big oversight to me. While the filesystem’s designers considered the hardware-level guarantees to be sufficient [1], this issue shows that there is an entire class of problems that they have not considered. Disk images and loopback-mounted filesystems or even disk-level cloning introduce additional layers of complexity where a filesystem can be silentl…

APFS not having block or file-level checksums really seems like a big oversight to me.

It wasn't an oversight; it was a deliberate design decision.

Others replies have noted that maybe it was a performance issue, etc. But I think it's something much different. The real reason is that there is more downside than upside to reporting these errors.

Users would be very upset if iOS told them that there was a bad block in one of their precious selfies from last month. But they might not even notice or care about a few bad pixels in the image itself.

I'm just telling you what one big probable rationalization was for this decision. I'd personally want to know, but people on HN aren't "average" IOS users.

Re: MacOS may lose data on APFS-formatted disk images

#180

Earlier quoted context omitted.

It's rather obnoxious that they prod us to upgrade every other day while all this is in the news.

I updated day one and had usual apple problems (finder broke so I had to use my terminal, sometimes it wouldn't wake up from sleep so I had to force it to reboot, my fans would spin up for seemingly no reason). Most of the issues were fixed a week later or so. Anyway, I recently switched to Arch on a 2018 LG Gram and I'm not really missing anything. Battery life is great (8-12 hours of Firefox) and it has a quad core…

Thanks for mentioning the LG Gram. I actually didn't know LG sold laptops (they're not available in Canada) before your comment. I just ordered one online now! I insta-purchased it when I noticed the 2018 model still has USB 3 Type-A and HDMI ports. Ctrl-key in the corner instead of Fn-key and equal sized arrow keys are a bonus.

Fits my needs as a Macbook Pro replacement. Will be running linux desktop on it too. Probably elementary OS.

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