What is the lifespan of my SSD?

Here is the link to the several year long SSD endurance test from back around 2012 or so (mostly included MLC SSDs, but did have several TLC NAND SSDs which are now very common in today's SSDs).

https://techreport.com/review/the-ssd-endurance-experiment-theyre-all-dead/

Most of the SSD failures I have encountered supporting thousands of my organization's Macs were due to the SSD controllers failing to communicate. I've only encountered a few SSDs which failed for other reasons due to the NAND. I think I've only seen two SSDs fail due to an extreme number of writes.....they definitely far exceeded 600TB threshold, probably reached into PBs.

Most people will never be able to write enough data to their SSDs to have them fail for too many writes.

My first M1 Mac has 171 TB written after 3 years. Percentage used is 5%. It is a 500GB SSD. I definitely push it with the swap due to excessive number of browser windows & tabs open all the time.

Yes. But look at it this way ... you can't have it "repaired" until something actually breaks. Nothing is broken. Just use your machine and enjoy it and don't sweat the technicals you have no control over.

Apple does offer a low cost extended warranty if you wish to hedge your bet.

If you feel there is a problem here, then run the third party app EtreCheck and post the report here so we can review it for possible issues. The report will let us see which third party apps have ties into macOS which launch automatically at boot & login, plus it will contain performance metrics and summaries of system logs which may provide clues to a possible problem. The app sanitizes any personal information so it is safe to post the report here so we can use it to evaluate your Mac.

Even with the Intel Macs we never had any idea about the TBW allowed for those SSDs even when Apple utilized Samsung based SSDs. The SSDs on Apple Silicon Macs are no longer a typical SSD, but just the NAND chips embedded into the Logic Board. So there really is no way to know how much writing we can expect to do with these SSDs. In addition the TBW value also depends on the number of NAND chips being utilized and their capacity in relation to the overall size of the complete SSD. Plus the Apple Silicon Macs utilize these SSDs differently than with the Intel Macs so these SSDs do tend to get utilized more than older Mac models. I also recall some people reporting an issue early on about some excessive SSD writes which I think was related to the use of the GPU IIRC, but I don't recall where that information was posted and whether that was ever changed to lessen the wear.

Generally many SSDs have at least a 150 TBW but could have 300 TBW or more depending on all those aspects I mentioned. I gernerally assume TBW to be somewhere in this range for the majority of SSDs when at least two NAND chips make up an SSD of 256GB or larger. Of course with higher density NAND chips, the smaller SSDs will have lower TBW ratings so these numbers will change over time for various size SSDs.

So far in my own personal experiencing supporting thousands of our organization's Apple laptops....most SSDs fail due to controller issues. I have seen very few SSDs fail due to NAND issues or due to exceeding their thresholds for writing. Recently I have encountered several of our Intel Macs where the SSD has failed due to excessive writes, but I am not sure of the reason since very few of our users even write significant amounts of data to an SSD....seeing several laptops encounter incredible number of SSD writes is starting to get my attention since they are happening at about the same time....no idea if it is the users, our configuration, or some unknown issue with macOS/apps, or a hardware issue with the SSDs. It is hard to confirm the reason since Apple SSDs have a very limited amount of health information available to analyze the issue. It is something I'm watching though, but so far the cases have been limited to just a few systems. The only other times I have legitimately seen any of our SSDs with excessive writes into the PB range were Macs we were utilizing as "servers" so that was not unexpected.

Really the only thing under your control is the third party apps and configuration of the laptop. The EtreCheck report may help us in that regards if you want assistance.

The TBW values are heavily dependent on the drive size!

So if you compare two drives of the same brand and model it depends on the size e.g. the 1 TB version has a TBW of 600 TB and the 2TB version of 1200TB, what do you see the TBW per TB is equal, guess what TBW has a 500GB version and what a 250GB version. So if you compare TBW values make sure you compare for the same capacity. Of course there are different tiers of SSDs. In my PC I have for example a Transcend device with 4400TW for a 2TB device which is a quite high value, the Samsung e.g. has 1200 TB as TBW.

For the apple devices it will be similar the 500GB will have double the TBW of the 250 GB version. (equivalent for 1TB, 2 TB, 4TB and 8TB). The normed value of TBW per TB Capacity will be equal. There is no apple specific physics.

My SSD (same model except 2 TB SSD) broke after a year of use. A friend's 16" did so as well.

Wait! How do you check TBW of ssd?

ps it eventually wasn't broken but just needed a firmware reinstall by apple. (My friends' ssd was gone, however.)

That's a very technical question and Apple generally doesn't release specifics about their components other than what's already published

As to mb being written, that process is pretty much a constant one as the Mac communicates with the drive. No drive is truly inactive when the system is powered up.

Your drive is fully capable of providing effective service for many years. TBW is not something you can change, but if you want to use an external drive to "spread the load around" that's your choice. But I suspect the marginal gain will be minimal if any at all. Your internal drive is going to do its job regardless of add-ons and they likely will increase the work level.

350 TBW is the typical low-end, and drives as high as 1200 TBW are available.

Bloggers who ran experiments to write drives to their death to see what happened did not see ANY weird things happen until nearly TWICE the TBW had been exceeded. At that point, a few blocks MAY start to get corrupted, but the entire device does NOT "fall off a cliff"

Punchline:

For most use cases, TBW is high enough you can simply put it out of your mind, you won't see those effects in ordinary use.

Yep, I misread your post at first.

Yeah, these are kernel task is a apple cpu/ram manager. launchd is a task thats also from apple and manages deamons and agents. These Tasks cant be more safe

<<. its at 6.1TBW (in 1 year). >>

oh, no! it might not work so well ...

.... in about 60 years.