Le 2024-12-26 11:59, Hakan Bayındır a écrit :
So making any assumptions like we did with spinning drives is mostly moot at this point, and the industry is very opaque about that layer.
That's one of the reasons why I think benchmarking would help here. I would expect fewer but larger write operations to help with the wear issue though, most FTLs especially the ones on cheaper media are probably not too smart and may end up erasing blocks more frequently than what is actually necessary with many scattered small writes.
Let's not forget that any server running with a RAID controller will already have a battery backed or non-volatile cache on the card, plus new SSDs (esp. higher end consumer (i.e. Samsung 6xx, 8xx, 9xx and similar) and enterprise drives have unexpected power loss mitigations in hardware. Let it be supercapacitors or non-volatile caches.
Sure, but the issue at stake here is that in some cases the expected data hasn't even been sent to the hardware when the power loss (or system crash) occurs. So while the features above help improving performance in general (which in turn may contribute to reduce the window of time in which the system is vulnerable to a power loss) they do not resolve the issue.
Cheers, -- Julien Plissonneau Duquène
