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I just bought a new Mac Mini (2020) with 512 GB flash storage.

As the flash storage of this model is soldered to the Mainboard this means to me if the flash fails the Mac mini will be dead. As this Mac is used for tasks require heavy disk usage (I expect about 2-4 TB per month) I tried to find out what maximum write load the Apple SSD is supposed to have.

Retail SSDs for PCs usually have a maximum Terabytes Written value indicating a supposed maximum write load they should be able to handle. Does such a value also exists for the integrated SSDs of a Mac mini?

Where can I find those values for the integrated Mac mini SSD - model number "APPLE SSD AP0512M"?

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  • Gentlemen - Robert is allowed and encouraged to ask a subjective question if that’s what they want. There is space for a good objective question or three here on Ask Different as companions to this question. If people want to answer this topic based on hard TBW targets, that may be a better option than forcing an edit to the intent here. Let’s not insist this question be that other question. Votes can sort out which versions of SSD write exhaustion question(s) are most helpful later.
    – bmike
    Mar 23, 2021 at 8:05
  • Comments are not for extended discussion; this conversation has been moved to chat.
    – bmike
    Mar 23, 2021 at 8:07

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I've had my 2018 Mac mini with 512 GB since November 2018 (around 580 days). According to DriveDx, the on-board SSD has been powered on for 28 days, despite the fact that the Mac has been switched on almost permanently.

The drive has written a total of 17,1 TB of data, according to the SMART data from DriveDx. I've heard 300-600 TBW bandied about as a typical SSD lifespan. (300 for the blade on a 2014 MBP; 600 for a 2018 Samsung EVO NVMe.) In which case, I've used about 0.06% - 0.03% of the drive's writes.

So it should last me 26-52 years. You may be able to extrapolate a result based on your own usage.

If you are expecting to write 8 times the disk's size every month, then using a larger external drive, which can be replaced more cheaply if necessary, may be a safer/better option.

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  • When starting with theoretical values you forget to mention that the SSD size has a very strong impact on the maximum TBW value, hence 300-600 TBW is only a valid value for a certain SSD size. Second your SSD values are nice but totally irrelevant for an answer, as my disk usage is much higher (up to 4TB per month). Hence it makes a big difference if the SSD has 300 or 600 TBW as maximum value for me as this means 6 or 12 years life time of the whole Mac.
    – Robert
    Jun 18, 2020 at 14:02
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    @Robert How could benwiggy know your data usage (up to 4TB per month) if you failed to mention that specific fact in your question? Good answers come from good questions...
    – Solar Mike
    Jun 18, 2020 at 14:09
  • @SolarMike I was writing require heavy disk usage because I can do math myself. I don't need somebody doing that for me, I need just the values to fill in the calculation. For nearly every SSD on the market this is not a problem. Just stupid Apple does not tell you anything about it.
    – Robert
    Jun 18, 2020 at 14:14
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    Apple buys its NVMe flash from Samsung. It's going to be off-the-peg. If you can indeed get data for nearly every SSD on the market, then you may be able to get a more precise range. However, with sunch large data requirements, are you really going to keep the Mini for 6-12 years? But a larger external would seem to make more sense.
    – benwiggy
    Jun 18, 2020 at 14:43
  • @benwiggy The mac mini that has ben replaced by this model was from 2013 therefore yes I expect a computer to work for up to 8-10 years if it is necessary. My point of view is the opposite: Why should I not expect such a life-time? If the computer is still fast enough of it's job it does not matter if it is 2 or 6 years old. The times where you replace a computer every three years are long gone.
    – Robert
    Jun 18, 2020 at 15:00
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As mentioned in the other answers, Apple does not give those specifications in their documentation or on their web site.

You can get some kind of estimate by installing the program smartctl from smartmontools, which can query your specific drive for its health parameters. Do this by installing HomeBrew, and then run the following in the terminal:

brew install smartmontools

After installation query the drive using:

smartctl --all /dev/disk0

You will now get the SMART health information for your drive. In particular take a look at the "Percentage Used". That gives a vendor specific estimate of the life used based on actual usage and a prediction of life time. It does not mean that the drive fails at 100% (the value can be more than 100), nor does it guarantee that it does not fail before reaching 100%. It is after all an estimate.

For example my Mac Mini shows that 36 TB data has been written to it (translates into 9 months of usage for you if your numbers are correct). This translates into an estimated 1% used. Had I used that 1% over 9 months, then it would translate into an estimated life time of roughly 75 years.

NOTE: My Mac Mini has the 2 TB version of the SSD, not the 512 GB version you have. The 2 TB version is expected to have a much longer life expectancy than the 512 GB version - so you cannot use my numbers for your drive. You have to check your own drive.

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Apple does not publish TBW / write duration / MTBF guidance for any product (thus far). Additionally, they don’t publicly commit to any specific vendor for components (or allow their vendors to claim they supply Apple ) as qualified for use with the T2-based storage controller.

On a technical level, the OS tracks storage writes daily in the diagnostic logs and the more people that opt in to share that with Apple, the better chance we all won’t be surprised if machines as a group are trending to exhaust their useful lifespans. My expectation is that Apple likely have an extraordinary pool of anonymous data on actual usage patterns on top of mountains of design and test data on how every system they release works and fails. Since we don’t see that data, we can’t depend on it for comfort or decision-making, naturally. It would be shocking if the decade of iOS storage data has left Apple unaware of how to design the T2 and M1 but no company is infallible and risks taken can turn into a service program to remediate longevity issues. All of these are standard Apple plays from their engineering and product delivery playbook.

Everything I write above applies to the 2020 Intel Mini and the 2020 Apple Silicon (M1) Mini. Much of the below focuses a bit more on the M1 controller and “blogosphere” of Apple tech writers and pundits.

There is a lot of FUD recently (podcasts and some MacWorld articles to be specific) concerning the first generation of M1 hardware and using S.M.A.R.T monitoring tools to analyze storage data. This is leading to speculation that write exhaustion might be a concern down the road. I don’t share that concern yet (mostly too soon to tell) and I would say most people are not alarmed or concerned about Intel based SSD that you specifically questioned. I encourage anyone that wants to watch this to do so and share their objective data and subjective experiences as well as hard data that can be verified and replicated. So far, no one is being bold enough to make actual hard prediction that Apple has made a fundamental or egregious error here.

Wear leveling on SSD is both non-trivial and very technical and sometimes considered proprietary / confidential data. After all, successful engineering of the constraints and costs and firmware and software over time - if this all is managed in balance, that results in a competitive advantage for Apple and the vendors alike. If mismanaged, it results in bad press, dissatisfied customers and erosion of margin or direct charges due to AppleCare costs and other claims.

There are people with legitimate desire to have Apple not design hardware that runs for decades - they call this an “Apple Tax” when enterprise grade parts / higher level of support and software upgrades ship in a consumer device. There are people with legitimate desire to have everyone subsidize enterprise grade parts / service and support in a consumer device so they can keep Macs in service for decades. Only time will tell if 5 to 7 years from now the M1 storage holds up as solidly as that of the Intel era, but I’m sure the journey to get there will be interesting.

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