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Why I'm Usually Unnerved When Modern SSDs Die on Us (utoronto.ca)
Chris Siebenmann, a Unix Systems Administrator at University of Toronto, writes about the inability to figure out the bottleneck when an SSD dies: What unnerves me about these sorts of abrupt SSD failures is how inscrutable they are and how I can't construct a story in my head of what went wrong. With spinning HDs, drives might die abruptly but you could at least construct narratives about what could have happened to do that; perhaps the spindle motor drive seized or the drive had some other gross mechanical failure that brought everything to a crashing halt (perhaps literally). SSDs are both solid state and opaque, so I'm left with no story for what went wrong, especially when a drive is young and isn't supposed to have come anywhere near wearing out its flash cells (as this SSD was).
(When a HD died early, you could also imagine undetected manufacturing flaws that finally gave way. With SSDs, at least in theory that shouldn't happen, so early death feels especially alarming. Probably there are potential undetected manufacturing flaws in the flash cells and so on, though.) When I have no story, my thoughts turn to unnerving possibilities, like that the drive was lying to us about how healthy it was in SMART data and that it was actually running through spare flash capacity and then just ran out, or that it had a firmware flaw that we triggered that bricked it in some way.
(When a HD died early, you could also imagine undetected manufacturing flaws that finally gave way. With SSDs, at least in theory that shouldn't happen, so early death feels especially alarming. Probably there are potential undetected manufacturing flaws in the flash cells and so on, though.) When I have no story, my thoughts turn to unnerving possibilities, like that the drive was lying to us about how healthy it was in SMART data and that it was actually running through spare flash capacity and then just ran out, or that it had a firmware flaw that we triggered that bricked it in some way.
Seriously, you do not. You may know the end-result sometimes (head-crash), but the root-cause is usually not clear.
So get over it. It is a new black-box replacing an older black-box.
Most ACs are not even worth the keystrokes to insult them. Be generically insulted by this and ignored otherwise.
I've had two SSDs die utterly. It wasn't because there was a failure of any part of the actual storage pathways: it was irreparable failure of the embedded controller circuits. The Flash itself was still fine and safely storing all my data, but there was no means to access it. At least with a platter drive if the PCB fails, you can unscrew and detach it and replace it with a matching PCB from another drive; no way to do that with an SSD. Early on when manufacturers were spending all their time hyping the comparative robustness of the Flash medium, they conveniently forgot to mention how fragile and not-so-robust the embedded third-party controller circuits could be.
Infant failures are common in electronics ( https://www.weibull.com/hotwir... ) From a simple standpoint, imagine a poorly soldered junction on the PCB - soldered well enough to pass QC and work initially, but after a couple of heating cycles the solder joint fractures. The same kinds of problems occur inside chips - wire bonds between the package and die may be defective but initially conductive, and fracture due to thermal cycling.
Similar problems can occur on the die. The gate oxide for a particular transistor might be too thin due to process issues. If it's way too thin, it'll fail immediately and the die will get sorted out at test. If it's just a bit thicker, it might pass all production tests but fail after an hour or two of operation, or 100 power cycles. If it's just a bit thicker (where it should be), it might last for 20 years and a million power cycles.
Everyone in the semiconductor industry would love to figure out how to eliminate these early failures. No one has found a way to do it.
And the worms ate into his brain.
I'm a retired IT guy and there's no kind of something that didn't fucking break. I'm not a goddam engineer. My job was to locate the problem at a black-box level and get the shit running again. Contemplating the "why" of a hardware failure is wheel-spinning instead of pulling the stuff out of the ditch.
For new purchases under warranty, I exchanged them and sent the dead one back to the vendor. Let them hook it up and do diagnostics over a cup of coffee.
I had work to do.
It little behooves the best of us to comment on the rest of us.
One thing I like about spinning disks is that a lot of times the failure is gradual. Bad sectors and such and you have the opportunity to grab data off the drive (noting, you really should have backups).
With SSD, whatever the issue, it's more like losing a controller board on the drive, everything dies and ceases to operate.
So... I'll go along and say SSD is "better" and more "reliable", but when it dies, it dies hard. Just the way it is. (not talking about performance degradation... speaking about failure)