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Comment by stackskipton | Hacker News Reader

Most flash has average wear out after 300k cycles. Let's say 64GB is used for swap. That's 19200 TB or 19.2 PETABYTES of Swap usage. Let's say you swap 12GB a day, you will burn out that 64GB of Flash Storage in 4.38 years and my guess is that amount of swap usage is extremely high that user would probably replace laptop sooner out of performance frustration.

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>Most flash has average wear out after 300k cycles

No it doesn't. Most 1TB drives are rated for around 600 TBW, so enough to overwrite the drive 600 times, nowhere near 300k cycles. If you search for specs of NAND chips used in SSDs, you'll find they're rated for cycles on the order of hundreds to thousands, still nowhere near "300k".

https://www.techpowerup.com/ssd-specs/crucial-mx500-4-tb.d95...

Original mid-90s Toshiba "solid state floppy disk" SLC flash: 1M cycles

2000s SLC flash: 100K cycles

Modern SLC/pSLC flash: 30-60K cycles

2010s MLC flash: 5-10K cycles

Modern QLC flash: 300-500 cycles

...and I won't even get into the details of their retention characteristics, suffice to say they subtly redefined them over the years to make the newer numbers better than they really are.

12GB a day isn't very much. If your working set is larger than the 8GB RAM, you're swapping multiple times per second. It doesn't take very many megabytes per swap to reach 12GB if you're doing that multiple times per second.

that doesn't maths

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