What is the lifespan of a Macbook Air 2018 SSD?

Question

Solid State Drives

Hello!
I want to buy a Macbook Air 2018, but because The SSD in it is soldered on the board, the question arises:
All my SSDs (Samsung, Plextor) lived no more than 4-5 years, it turns out that the Macbook Air will also live?
I understand there is a type of MLC memory chips?
Thank you.

Answer 1

I will say right away - don’t even worry about the lifespan)
One of the main factors in the lifespan of an SSD is the number of overwrites per disk cell. The larger the drive and the more allowed write cycles, the longer it will last. The type of SSD with TLC has 500-1000 (possibly more) cell rewrite cycles, and accordingly there is such a parameter as TBW (Total Byte Write), - the total number of bytes that can be written to disk, after which the memory cells will use up their resource.
SSDs in MacBooks are good quality and have a lot of write cycles, but they are expensive. If you compare your SSDs with those used by Apple, the numbers will be very different in Apple's favor - both in price, write cycles, and so on. For drives such as iMac/MacBook, manufacturers promise a service life of up to 10 years.
And now let's count. Let's say the SSD in the MacBook Air 2018 has a capacity of 128GB and 800 rewrite cycles per memory cell, and the hardware is changed every 4 years on average. The manufacturer claims a service life of up to 10 years.
1. " To ruin a disk in 4 years, you need ... ":
a) TBW = 128GB * 800 cycles / 1024 = 100 TB of information can be written to disk so that memory cells fail.
b) 100TB / (4 * 365 days) * 1024 = 70 GB needs to be overwritten per day so that the disk becomes unusable in 4 years.
c) DWPD = 100TB / (128GB * 4 * 365 days) * 1024 = 0.54 - the number of overwrites of the entire drive volume per day (out of 800 allowed).
2. Time of life, taking into account errors : The
average user writes-deletes 20GB of information daily (taking into account the load of software on the disk).
100 TB * 1024 / (20 GB * 365 days) = 14 years of disk life, we take into account various external factors affecting the life of the SSD = we get 8-11 years of SSD uptime for the MacBook Air 18g.
3. " If the volume is doubled ":
Exactly the same disk, but with a memory capacity of 256GB, will have figures increased by 2 times.
For example, TBW = 200TB or 140 GB/day overwrite over 4 years. But DWPD will remain the same and the service life will also be up to 10 years.
a) MacBook Air 2018 with 128GB will have a disk life of 8-11 years under the condition of the average user;
b) If you bought inexpensive SSDs with 128-256GB of memory with a smaller rewrite cycle, the service life for them is 4-6 years - as happened in your case;
c) For more voluminous media, the TBW indicator can reach 900TB, and even higher.

Answer 2

What is the lifespan of a Macbook Air 2018 SSD?

If we get lucky.
It might break right away, it might take ten years.

I understand there is a type of MLC memory chips?

Unlikely. But what does it matter in the context of the question?
The type of memory does not affect the failure of the controller.