https://www.usenix.org/conference/fast16/technical-sessions/presentation/schroeder
Ukratko nalazi o trajnosti i pouzdanosti u Google serverima 10 različitih vrsta/brandova SSD-ova u zadnjih 6 godina upotrebe pokazali su:
-nema razlike u trajnosti i pouzdanosti između MLC, eMLC i SLC verzija.
-na pouzdanost više utječe starost diska nego količina pisanja/brisanja
- od 20 do 63% diskova prijavilo barem 1 "uncorrectable error" za vrijeme prve godine rada
-30-80% ssdova prijavilo barem jedan bad block, i 2-7% barem 1 bad chip u prve 4 godine službovanja
-RBER (raw bit error rate) i UBER (uncorrectable bit error rate) nisu dobri pokazatelji za failure u praksi. RBER i UBER rastu linearno
citat zaključka na engleskom, da ne petljam "izgubljen u prijevodu":
- While flash drives offer lower field replacement rates than hard disk drives, they have a significantly higher rate of problems that can impact the user, such as uncorrectable errors.
- Drives tend to either have less than a handful of bad blocks, or a large number of them, suggesting that impending chip failure could be predicted based on prior number of bad blocks. The above are rather interesting and perhaps surprising conclusions. Quite a few of the surprises are pleasant. However the way that flash-based drives tend to fail should encourage users to be even more regular with their backup regimes.
