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Upgrading an M4 Pro Mac mini's storage for half the price

(www.jeffgeerling.com)
420 points speckx | 18 comments | 11 Jul 25 14:06 UTC | HN request time: 1.741s | source | bottom
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GeekyBear ◴[11 Jul 25 15:55 UTC] No.44533662[source]▶
The article speculates on why Apple integrates the SSD controller onto the SOC for their A and M series chips, but misses one big reason, data integrity.

About a decade and a half ago, Apple paid half a billion dollars to acquire the patents of a company making enterprise SSD controllers.

> Anobit appears to be applying a lot of signal processing techniques in addition to ECC to address the issue of NAND reliability and data retention. In its patents there are mentions of periodically refreshing cells whose voltages may have drifted, exploiting some of the behaviors of adjacent cells and generally trying to deal with the things that happen to NAND once it's been worn considerably.

Through all of these efforts, Anobit is promising significant improvements in NAND longevity and reliability.

https://www.anandtech.com/show/5258/apple-acquires-anobit-br...

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throw0101c ◴[11 Jul 25 16:14 UTC] No.44533915[source]▶
> The article speculates on why Apple integrates the SSD controller onto the SOC for their A and M series chips, but misses one big reason, data integrity.

If they're really interested with data integrity they should add checksums to APFS.

If you don't have RAID you can't rebuild corrupted data, but at least you know there's a problem and perhaps restore from Time Machine.

For metadata, you may have multiple copies, so can use a known-good one (this is how ZFS works: some things have multiple copies 'inherently' because they're so important).

Edit:

> Apple File System uses checksums to ensure data integrity for metadata but not for the actual user data, relying instead on error-correcting code (ECC) mechanisms in the storage hardware.[18]

* https://en.wikipedia.org/wiki/Apple_File_System#Data_integri...

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GeekyBear ◴[11 Jul 25 16:34 UTC] No.44534176[source]▶
> If they're really interested with data integrity they should add checksums to APFS.

Or you can spend half a billion dollars to solve the issue in hardware.

As one of the creators of ZFS wrote when APFS was announced:

> Explicitly not checksumming user data is a little more interesting. The APFS engineers I talked to cited strong ECC protection within Apple storage devices. Both NAND flash SSDs and magnetic media HDDs use redundant data to detect and correct errors. The Apple engineers contend that Apple devices basically don't return bogus data.

https://arstechnica.com/gadgets/2016/06/a-zfs-developers-ana...

APFS keeps redundant copies and checksums for metadata, but doesn't constantly checksum files looking for changes any more than NTFS does.

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1. protimewaster ◴[11 Jul 25 16:52 UTC] No.44534374[source]▶
That solution doesn't help anyone who's using external storage, though, so it kinda feels like a half billion dollars spent on a limited solution.
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2. GeekyBear ◴[11 Jul 25 17:07 UTC] No.44534607[source]▶
There is nothing preventing you from running OpenZFS on external storage if you are worried that the hardware you purchased is less reliable.
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3. protimewaster ◴[11 Jul 25 17:28 UTC] No.44534859[source]▶
That's my point, though, is that it seems weird to spend a half billion dollars just to solve the problem for an extremely common use case by saying "use OpenZFS".

Why not come up with a solution that covers external storage too, instead of spending all that money and relying on external solutions? I just don't understand why they couldn't have optional checksums in APFS.

replies(1): >>44535056 #
4. slt2021 ◴[11 Jul 25 17:42 UTC] No.44535017[source]▶
maybe apple doesn't want you to use external storage, because storage size is how apple upsells devices and grabs larger premium.

By using external storage, instead of paying $10k more for more storage, you are directly harming Apple’s margins and the CEO’s bonus which is not ok /s

replies(1): >>44535999 #
5. GeekyBear ◴[11 Jul 25 17:45 UTC] No.44535056{3}[source]▶
It's far more weird that NTFS still makes zero effort to maintain file integrity on any level, on internal or external disks.

ReFS exists, so Microsoft knew they needed to do something, but they have utterly failed to protect the vast majority of users.

replies(1): >>44536073 #
6. creddit ◴[11 Jul 25 18:48 UTC] No.44535664[source]▶
No one requires you to use APFS for your external storage!
replies(1): >>44535749 #
7. amethyst ◴[11 Jul 25 18:57 UTC] No.44535749[source]▶
And yet it's the default when formatting a device on macOS.
replies(1): >>44535985 #
8. dylan604 ◴[11 Jul 25 19:25 UTC] No.44535985{3}[source]▶
Being afraid to not use the default is evidence of not being a power user!
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9. dylan604 ◴[11 Jul 25 19:27 UTC] No.44535999[source]▶
Externally connected devices are not sexy, and Apple is concerned about image and looking sexy.
10. protimewaster ◴[11 Jul 25 19:34 UTC] No.44536073{4}[source]▶
To be fair, though, NTFS predates APFS by over 20 years.

Don't get me wrong, there's no reason Microsoft can't transition to another filesystem (like offering ReFS outside of Server or whatever Windows variants support it currently), but I don't understand why a company would transition to a new filesystem in 2016 and not include a data checksums option. Hell, ReFS predates APFS, and I think it even has optional data checksums.

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11. GeekyBear ◴[11 Jul 25 20:58 UTC] No.44536728{5}[source]▶
To be fair, NTFS is still the default Windows 11 filesystem in 2025, and Microsoft still makes zero effort to insure file integrity when you use that default Windows filesystem.

Handling file integrity in hardware is a big step up.

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12. protimewaster ◴[11 Jul 25 21:56 UTC] No.44537155{6}[source]▶
> Handling file integrity in hardware is a big step up.

Is there any evidence that Apple actually has better hardware data integrity than anyone else, though? They make claims in the article linked a few posts back, but AFAIK SSDs in general make use of error correcting codes, not just Apple's SSDs.

That article also points out how even multi-million dollar arrays are known to return bad data, and previous Apple SSD devices have been known to do the same.

I agree that the state of default filesystems is bad, but I'm not convinced that Apple's hardware solution is anything more than them saying, "Trust me, bro."

13. p_ing ◴[11 Jul 25 22:04 UTC] No.44537220{5}[source]▶
ReFS is available on Windows 10/11 client; it's what the DevDrive feature uses. And the current Insider allows installation of the OS/boot volume on ReFS.

https://forums.guru3d.com/threads/testing-instaling-windows-...

14. whartung ◴[11 Jul 25 23:35 UTC] No.44537901[source]▶
Every time I tried OpenZFS on my iMac, it absolutely crushed the performance of the entire machine.

We’re talking “watch the mouse crawl across the machine” crushed. Completely useless. Life returned to normal when I uninstalled it.

Also, I’ve heard anecdotes that ZFS and USB do not get along.

I’ve also heard contrary experiences. Some folks, somewhere, may be having success with ZFS on external drives on an iMac.

I’m just not one of them.

15. pjmlp ◴[12 Jul 25 06:25 UTC] No.44539806{4}[source]▶
Occasionally that is mistaken by newbies as such, oftentimes it is the voice of experience and battlefield scars driving sensible decisions.
16. avhception ◴[12 Jul 25 09:39 UTC] No.44540679{4}[source]▶
Default or not, are there sensible alternatives on a Mac? I'm not sure if I'd consider OpenZFS on Mac "sensible" - but I haven't owned a Mac in decades, so... what are the alternatives to APFS?
17. 1over137 ◴[12 Jul 25 13:14 UTC] No.44541855[source]▶
Apple does not care about external storage at all, as in external disks. They offer iCloud for external storage. They don't sell external disks. They don't like cables. They make lots of money selling you a bigger internal disk.
replies(1): >>44543014 #
18. realityking ◴[12 Jul 25 16:06 UTC] No.44543014[source]▶
Their store has a whole section dedicated to storage, most of it external. https://www.apple.com/shop/mac/accessories/storage