• Forums
  • Shop
  • iPhone 13
  • AirPods Deals
  • iPad Deals
  • Best Apple Watch
  1. Home
  2. /
  3. News
  4. /
  5. Apple
Oh boy

M1 Mac users report alarming hard drive health readings

"If this is accurate, some of these machines aren't going to last half a year"
Stephen Warwick
23 Feb 2021

Macbook Air M1Source: Daniel Bader / iMore

What you need to know

  • M1 Mac users are reporting extremely troublesome health readings from their SSDs.
  • The TBW (total bytes written) figures show the life spans of these hard drive scould be in real danger.
  • There is hope however that a software bug is behind the issue.

There are numerous reports from M1 Mac users that macOS is giving out worrying hard drive health reports which could indicate severe life span problems.

From the LTT forums:

Some more professional users of the new M1 Macbooks are experiencing extremely high drive writes over relatively short time.

The most severe cases have "consumed" about 10-13% of the maximum warrantable TBW value of the SSDs (given their capacity & using values for equivalent market-available NVMe drives).

2TB 16GB model. 3% used.

That means that for a 256GB model, proportionally, you'd expect ~30% usage.

If this is accurate, some of these machines aren't going to last half a year to 100%.

And that's a 16GB model. 8GB should be worse.

Holy shit. https://t.co/9HcmaYgJPT

— Hector Martin (@marcan42) February 15, 2021

M1 Mac SSD update…

Apple, this is NOT okay. Especially as the internal SSD isn’t replaceable. The machine is just a bit over 2 months old. pic.twitter.com/xqlSMjxwTa

— Longhorn (@never_released) February 13, 2021

The issue of 'TBW', or total bytes written, refers to the lifespan of an SSD. As explained by PC Gamer:

Core to what's going on is the way in which SSDs work, specifically the number of writes they can reliably support. The flash memory on the drives can only be written to a certain number of times before becoming unstable. There are plenty of systems in place to spread the load across all the memory cells, but essentially there's a point where the drive has been written to so many times that it can no longer reliably hold the information.

This is all summed up by the Total Bytes Written figure, measured in terabytes (which is why it's also referred to as Terabytes Written). This needs to be considered in the context of the length of the warranty, which is generally five years.

If the readings being given out from these machines is correct, developer Hector Martin says it could indicate that some machines "aren't going to last half a year":

2TB 16GB model. 3% used.

That means that for a 256GB model, proportionally, you'd expect ~30% usage.

If this is accurate, some of these machines aren't going to last half a year to 100%.

And that's a 16GB model. 8GB should be worse.

Holy shit. https://t.co/9HcmaYgJPT

— Hector Martin (@marcan42) February 15, 2021

Martin does however state this is "definitely" a bug, however its unclear if that relates to the readings being given, or macOS behavior which is causing the readings to be abnormally high (but accurate). As PC Gamer notes in its report, smart monitoring tools "are notorious for misreporting" and this could be an M1 teething problem.

An update from Hector last week noted M1 SSD isn't proportional to driver size, so the "less than one-year" scenario is very unlikely:

Update on M1 SSD wear issue: Available data suggests that write endurance ratings are not proportional to drive size.

256GB model: ~2000TB [1700-2300]
2TB model: ~5000TB [4300-6000]

This means that @david_rysk's currently known worst case would push a 256GB model to 100% in ~2y

— Hector Martin (@marcan42) February 16, 2021

Martin described this as "still way too fast, but not as bad as we previously thought". Martin further notes that the problem isn't exclusive to the M1 Mac, and that some Intel users have also been seeing strange readings. Most recently, Dan Seifert on Twitter:

https://twitter.com/dcseifert/status/1364206594117038087?s=20

Seifer noted the issue was "all swap" caused by a 'Hand Mirror' app, and that closing it meant he could watch his SSD "reclaim free space in real time".

SSDs can continue to operate once the TBW limit is reached, however, there is no guarantee as to how long it can last. As such, Apple will no doubt be working on a fix for this in macOS, either to fix faulty readings or to rectify the behavior behind them.

Tune in on Tuesday to check out some third-party games on Nintendo Switch!
Direct access

Tune in on Tuesday to check out some third-party games on Nintendo Switch!

Ready for the next big announcement from Nintendo? Here's what you need to know!

M2 benchmarked against other Apple silicon, reminds us M1 Ultra is top dog
Speedy

M2 benchmarked against other Apple silicon, reminds us M1 Ultra is top dog

While all of the talk right now is about Apple's new M2 chips, it's easy to forget that the best Apple silicon money can buy right now is the M1 Ultra — but this latest round of benchmarks soon reminds us all.

How much longer can the Nintendo Switch go on?
Okay grandpa

How much longer can the Nintendo Switch go on?

Our favorite consoles will forever live in our hearts, but that doesn't mean they have to live forever on store shelves. When will Nintendo move on from the Switch?

Charge up your AirPods without plugging in
🔌 ⁉️ 🎧

Charge up your AirPods without plugging in

Looking for the perfect charging case for your AirPods that’ll let you boost your battery on the go? Here are the best of the best AirPods wireless chargers right now!

Keep in Touch

Sign up now to get the latest news, deals & more from iMore!

I would like to receive news and offers from other Future brands.

I would like to receive mail from Future partners.

No spam, we promise. You can unsubscribe at any time and we'll never share your details without your permission.

  • News
  • Apple Silicon
  • iPhone
  • iPad
  • Apple Watch
  • Mac
  • Apple TV
  • Reviews
  • How To
  • HomeKit
  • Forums

Other Categories

  • About Us
  • Newsletter
  • Fitness
  • Apps
  • Gaming
  • Deals
  • Advertising Inquiries
  • Licensing and Reprints
  • Accessibility Statement
  • Android Central
  • Windows Central
  • Thrifter
  • TechnoBuffalo
  • MrMobile
Log in or Sign up
  • t
  • f
  • y
  • i
  • r

Brightness

  • © Future US, Inc.
  • Terms & Conditions
  • Privacy Policy
  • Cookie Policy
  • About Us
  • Careers
  • Licensing
  • External Links Disclosure
  • Accessibility Statement
  • © Future US, Inc.
  • Terms & Conditions
  • Privacy Policy
  • Cookie Policy
  • About Us
  • Careers
  • Licensing
  • External Links Disclosure
  • Accessibility Statement