3 ms·
>very write intensive, and thus destroys the SSD I'm not going to argue about how Chia Coin works, but I'm always skeptical of claims about excessive writes de
by AussieWog93 5y ago
>very write intensive, and thus destroys the SSD
I'm not going to argue about how Chia Coin works, but I'm always skeptical of claims about excessive writes destroying SSDs.
From what I understand, this is mostly unfounded fear based on the fact that earlier MLC cells were specced for a minimum of 10,000 write cycles and people extrapolated 5-10 year life expectancies from that. In practice, though, testing showed that the typical cell could be rewritten around 1,000,000 times, and the controllers would just route around the weaker cells that died early.
Anecdotally, even though consumer SSDs have been mainstream for around a decade now, I have not heard, IRL or online, of a single person complain that their SSD has failed (manufacturing defects such as the Sandforce firmware bug aside). At the same time, I've personally witnessed dozens of HDD failures.
I don't fully understand why fear around consumer SSDs is still a thing, but I suspect it's exactly the same "Reddit expert" social dynamic that drives the advice around thermal paste application.
- dorkwood 5y agoThe claim comes from Chia devs themselves, who recommend not using consumer-grade drives due to their low endurance. > The one thing in common will be that you need high endurance, due to the fact that it take almost ~1.8TB of writes using the -e flag or 1.6TB without that option to create a single K=32 plot. > Endurance is how much data can be written to the SSD before it wears out. In Chia this is important because a plotting SSD will generally be at 100% duty cycle and writing all day. > A mixed use or high endurance data center or enterprise SSD is the best choice for plotting. Used SSDs with plenty of endurance can be found for a good value on eBay, Craigslist, or similar. > Consumer NVMe SSDs are generally not recommended due to the lower endurance, and they often employ caching algorithms to faster media (SLC, or single level cell) for great bursty performance. They do not perform well under heavy workload sustained IO. There are very high performance consumer NVMe SSDs that will offer great plotting performance, but the lower rated endurance in TBW will result in a faster wearout. https://github.com/Chia-Network/chia-blockchain/wiki/SSD-End https://github.com/Chia-Network/chia-blockchain/wiki/SSD-End...
- baruch 5y agoDo you sources for the 1 million writes(erase) on MLC NAND? I work with enterprise SSDs and that number is well above anything I've seen or heard, even from the manufacturers.
- AussieWog93 5y agoI can't find a source for my original claim, but based on some real world tests[1] it looks like real-world performance is closer to 50-100k writes. It seems I misremembered the quantitative data, but the overall qualitative point (SSD Endurance is much, much higher than most "prosumers" believe) is accurate. [1] https://techreport.com/review/27909/the-ssd-endurance-experiment-theyre-all-dead/ https://techreport.com/review/27909/the-ssd-endurance-experi...
- baruch 5y agoMost drives these days are TLC and and consumers are more likely on QLC. I havent even seen an MLC drive for a while now.
- fomine3 5y agoGenerally agree, but Chia plotting is REALLY write intensive workload.