My impression was that even cheap SSDs should have ultracapacitors or small batteries that allow them to survive a power loss event without being bricked. Of course, the stuff in the cache is lost at that point, but that's no worse than the situation with a hard drive. Also, as I mentioned, "much more data than the one currently written" can be lost when power fails in a hard drive. So the situation is really no different, unless the manufacturer screwed up.
Spinning disks have enough rotational momentum to keep spinning (which keeps the heads floating) for long enough to park the heads via a weak spring, with zero electricity. A head crash doesn't corrupt a few sectors so much as cause catastrphic damage - that disk would likely never read another sector again. Properly-functionioning spinning disks haven't had issues with random data loss on power failure for at least a decade now.
And your impression of cheap SSDs is dead, flat wrong. They're cheap - every unnecessary part is left off to save money. And we've all (all of us who pay attention) known for years that SSDs (even some with power fail protection) will lose data (even bits which it has reported to have sync'd) on power loss.
A UPS is not enough, if you need to have your data, you need multiple layers of backup, and an SSD must have some method of writing out voltatile data (mostly internal metadata, not cache) before it shuts down.
Properly-functionioning spinning disks haven't had issues with random data loss on power failure for at least a decade now.
Source?
And your impression of cheap SSDs is dead, flat wrong. They're cheap - every unnecessary part is left off to save money. And we've all (all of us who pay attention) known for years that SSDs (even some with power fail protection) will lose data (even bits which it has reported to have sync'd) on power loss.
I think you misread what I wrote. I wrote that I would expect cheap SSDs to "survive a power loss event without being bricked." I did not write that they would retain all data, which seems to be what you are arguing against.
I have heard rumors that some cheap SSDs do not honor the SATA SYNC command. Unfortunately I do not have a reliable source for this theory, do you?
A UPS is not enough, if you need to have your data, you need multiple layers of backup, and an SSD must have some method of writing out voltatile data (mostly internal metadata, not cache) before it shuts down.
I don't think anyone is arguing that a UPS is a replacement for backups.
