Concerns Over SSD Swap Usage: Did I Make the Right Choice with My M2 Air?

Interpreting the health of Apple's NVMe SSDs is tricky since they contain very little health information. Plus some of the third party apps/utilities will list information according to older drives. Unfortunately many of the NVMe SSDs (especially Apple's) don't seem to update the normalized values so you may need to use the information listed in the new style reporting methods which do seem to show changes in the SMART attribute health information. Even then those health attributes only provide the most basic of health information making it hard to truly assess the SSD's health.

The only problem I have ever seen mentioned regarding the Apple M-series SSDs was at launch of the M1 Macs in 2020 where the SSD's SMART attributes were reporting an extremely high number of writes. Some speculated it was due to an incorrect reporting of the SSD, incorrect interpretation by the drive health monitoring apps, or from an issue with the GPU excessively writing to the SSD. It seems that issue was quietly resolved by Apple so we have no clue of the cause. Except for some M-series Macs containing just a single NAND chip for the SSD, I have not seen any other reported issues.

In my own personal experience supporting thousands of my organization's computers (mostly Macs), I have rarely encountered an SSD failure due to excessive writes. My organization has a handful of SSDs in systems with extremely high writes and only failed after reaching PBs of writes. The majority of SSD failures I've encountered (99%) have been due to other hardware issues with the SSDs usually involving issues with their built-in controllers which can suddenly fail with little or no notice. Here is an excellent article series from around 2013 where a group performed 24x7 stress test on some SSDs and ran them until they failed completely....it took several years and how the SSDs behaved during that time is interesting:

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

Apple has generally used higher quality NAND in their SSDs (usually from Samsung).

Having said all this, if you are using an excessive amount of Swap, then you most likely under spec'd your system memory for your current workloads. Fortunately the internal SSD is very fast so performance issues are less noticeable with Swap, but you do pay for it by wearing the SSD down sooner than if you were not using excessive amounts of Swap. Chances are the SSD will work into the PBs of writes.

KxAy wrote:

I'm somewhat concerned about the swap usage, given what I've read online.

There's an easy solution to your concerns. Stop reading that junk online. It's not true.

KxAy wrote:

so even with high amount of swap like 5gb, i should be fine?

I don't think you should be worrying about this.

Yes, you should have gotten at least 16 GB RAM. But I am typing this on a 2015 iMac with a new SSD as of May 2022, so it's about 2 years old. That old iMac has only 8 GB memory also. It is using 2.7 GB swap space. DriveDX tells me that the drive has between 98% and 100% of its lifetime left (depending on the various parameters it examines). Over the past 14 days it has read 950 GB and written 450 GB, not that different actually from yours. At this rate my SSD will be 50% of lifetime left in about 50 years. I think you are worrying unnecessarily about this, find something else to worry about!

KxAy wrote:

I'm puzzled by the widespread claim that the base SSD has a TBW of 150TB.

Who is claiming this? People on the internet? Social media influencers? It's not true.

I've seen people sharing their S.M.A.R.T. data, showing that after 10TBW, they have 95% of the SSD's life left. How is this possible, especially considering that my desktop SSD has been written to 104 petabytes with 87% lifespan remaining, and it's nowhere near the quality of Apple's SSD?

Apple doesn't publish low-level technical specifications about its SSD chips. Therefore, no 3rd party software tool can possibly know what those values are. Don't believe what you read on the internet.