Apple's Policy on Apple File System (APFS) for High Sierra

[AnAppleADay]

No. HFS+ bitrot - APFS will get new features as it goes along. Until then it has fsck (same as HFS+)

Thanks. I was more trying to ask, if HFS+ doesn't have checksums either, why delay APFS adoption for lack of checksums? It seems to me both are just as bad in this regard and that generally I'm better off with APFS than HFS+.

I read these articles yesterday and recommend them. The thread here on Tonymacx86 has been very helpful and very interesting!

http://dtrace.org/blogs/ahl/2016/06/19/apfs-part5/
https://pikeralpha.wordpress.com/2017/07/04/do-i-use-apfs/
http://dtrace.org/blogs/ahl/2016/03/07/big-news-for-zfs-on-linux/
https://developer.apple.com/library...Management/Conceptual/APFS_Guide/FAQ/FAQ.html

 

[Going Bald]

APFS is fine on a "real" Mac (for metadata), but disaster in the making for a PC-Mac and for user data.
APFS is looking at the firmware and ECC of a real Mac, which does not exist in a PC-Mac, so you not only have no checksum for user data, you also have nothing for metadata.
See pikeralpha's reply to funkyfrank on July 4 in the pikeralpha.wordpress link in post #23

On the 2008 iMac and 2012 MBP I have I am staying with HFS+, not only because of all of the 3rd party recovery apps available for HFS+ but because both Macs came with HDDs that I have not bothered to upgrade to SSDs.
Since APFS is optimized for SSDs it would be a waste of time to format a HDD with APFS.

On the Asrock Z77 build, the Asus Z77 and Z87 builds and the X58A builds I have upgraded to SSDs and they all run Sierra just fine, but I see no advantage to APFS when the firmware of a "real" Mac is not there for interaction with the APFS format and drivers.

 

[vulgo]

Thanks. I was more trying to ask, if HFS+ doesn't have checksums either, why delay APFS adoption for lack of checksums? It seems to me both are just as bad in this regard and that generally I'm better off with APFS than HFS+

Which filesystems do checksum data? Apparently APFS has a 'novel' copy on write operation for the metadata, which is also checksummed. No journalling. Apple's custom controllers on their SSDs have very robust (supposedly fool-proof) error checking code (e.g. at access time). All SSDs have a level of error checking code, varies by controller/firmware. You should backup your data whatever the filesystem, or redundancy level.

 

[AnAppleADay]

APFS is fine on a "real" Mac (for metadata), but disaster in the making for a PC-Mac and for user data.
APFS is looking at the firmware and ECC of a real Mac, which does not exist in a PC-Mac, so you not only have no checksum for user data, you also have nothing for metadata.
See pikeralpha's reply to funkyfrank on July 4 in the pikeralpha.wordpress link in post #23

OK, thanks GB! I appreciate it!!

I agree. It is very concerning that we don't know exactly what the apple firmware is doing. And user data checksums would be preferred.

I don't know the answer, however regarding not having metadata sums, I saw that Pikeralpha said "There are checksums only for meta data. Not the user data. Apple relies on ECC for (hardware) error detecting and correcting." I guess I thought PC-Mac would have metadata checksums on APFS.

Regarding ECC and real Macs, I saw a post by freesby on another forum regarding Pikeralpha's blog:

"Eh, He is just saying that Apple will implement ECC in their storage devices, but that's exactly what any other third party solid state device does. ECC is quite standard. https://en.wikipedia...rive#Controller. So standard that most vendors don't even mention it. https://www.kingston.com/us/ssd/data-protection. Apple is simply saying that their storage devices are so good that they won't even bother with implementing data checksum with their apfs.

This is a very good article about APFS. http://dtrace.org/bl...6/19/apfs-part1. An actual review with first hand accounts from Apple developers who created apfs. For daily use apfs is just fine, but if you are truly worried about your data then use more appropriate storage solutions. First step is to grab a good and reliable SSD or HDD with strong and bug free ECC firmware (which is what Apple is claiming with their devices and firmware).

I would assume that the APFS itself must be ready for daily use, since it is already shipped with iOS , tvOS 10.2, and watchOS 3.2, which represent millions of devices that people is using daily."​

 

[AnAppleADay]

Which filesystems do checksum data? Apparently APFS has a 'novel' copy on write operation for the metadata, which is also checksummed. No journalling. Apple's custom controllers on their SSDs have very robust (supposedly fool-proof) error checking code (e.g. at access time). All SSDs have a level of error checking code, varies by controller/firmware. You should backup your data whatever the filesystem, or redundancy level.

OK thanks Vulgo!! Yes, I should backup my data in any case.

 

[vulgo]

The filesystem driver just reads and writes to the disk, its not talking to the controller directly.

 

[masterscarhead1]

@RehabMan, is it possible to use the HS usb installer to format in HFS and keep it on HFS?

 

[RehabMan]

@RehabMan, is it possible to use the HS usb installer to format in HFS and keep it on HFS?

I assume you are asking about a fresh install scenario.

So far the only way I've found:
- use two partitions
- one HFS+J, second APFS
- install to the APFS partition first
- after install to APFS, use startosinstall to install to the first HFS+J partition
- remove APFS container/partition etc (with diskutil)
- expand HFS+J partition into the space freed by removing APFS

 

[MacAddict4Life]

Can I let High Sierra convert my SSD from HFS+ to APFS? If my clover install is up to date, what (if anything) do I need to do before or after to make sure my system will work?

 

[trs96]

Can I let High Sierra convert my SSD from HFS+ to APFS? If my clover install is up to date, what (if anything) do I need to do before or after to make sure my system will work?

Here's what Mike from CCC has to say about the transition to APFS:

There's a lot of excitement these days about the new APFS filesystem coming from Apple. I'm certainly excited about it; some of the promised features sound great. However, I'm going to make a bold suggestion: Wait a few months before upgrading to High Sierra this Fall. High Sierra may force the APFS conversion upon you, and I think it's common sense to wait for the new filesystem to get some more mileage before making the switch. Sticking with the tried-and-true HFS+ on Sierra for a few months may save you a lot of headaches and wasted time.

Developing a filesystem from scratch is a huge endeavor, and the pace of progression is impressive. But it's not ready, and I think Apple is pushing it too early. If APFS offered greater security over HFS+, then I could see an argument to move to this new filesystem at a faster pace. But APFS doesn't deliver substantively better security over CoreStorage Encryption on HFS+. There's no impetus to move to this new filesystem so soon after it is released.

I'm genuinely concerned about what kind of results we can expect if millions of users charge head-on into this infant filesystem on their production Macs. If playing with technology and learning about the new features of the OS and filesystem is your hobby, then by all means, make good backups and charge on ahead. But if that's not your hobby – if you wouldn't call yourself "technically inclined" or if you're the person that wants to use your Mac to do things rather than mess around with OS reinstalls and data recovery, then I urge you to patiently wait for a .1, .2, or even .3 release of High Sierra before taking the plunge.