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The advertised performance specifications for consumer SSDs are mostly useless. They pick the metrics that produce the biggest numbers, without regard to whethe
by wtallis 6y ago
The advertised performance specifications for consumer SSDs are mostly useless. They pick the metrics that produce the biggest numbers, without regard to whether those numbers have any relevance to real-world use. Those numbers are mostly useful for determining what class of controller and flash memory are used, in case the spec sheet doesn't list that information. Likewise for warranty period and write endurance ratings; those are more about signalling product segmentation than about actual expected lifetime.
For consumer SSDs, there's no need to worry about write endurance or QLC NAND unless you know you have a very atypical usage pattern and have actually measured your workload by eg. tracking SMART indicators on your current drive(s) for several days.
Brand matters very little unless you really care about the experience of getting a warranty replacement in the rare event that your drive fails before the warranty expires. I'm not aware of any solid information indicating that certain SSD brands have consistently lower premature failure rates. My anecdotal experience from reviewing SSDs for several years is that all the top-tier brands have at some point sent me review samples that were either DOA or died during testing that shouldn't have killed a drive.
Outside the top tier brands belonging to the NAND flash memory manufacturers, everyone is buying NAND on the open market from the same 2-3 manufacturers and buying SSD controller solutions from the same 2-5 vendors. There are literally dozens of retail models all using the same combination of Phison E12 controller and Toshiba/Kioxia 3D NAND, and the differences between these are almost entirely cosmetic. All the PCIe 4.0 consumer SSDs that have been released so far are functionally identical.
- mehrdadn 6y agoThis is great info, thank you! Regarding SMART indicators, do you know if they're generally reliable? I seem to recall there have been drives (at least HDD, not sure about SSD) that didn't report correct numbers. In fact, I just checked and my current SSD doesn't report SMART data at all. Have they gotten better over the years?
- wtallis 6y agoI don't make a habit out of doing sanity checks on the SMART reporting of drives I test. My tests log that data, but I haven't written anything to parse that into useful information. I can't recall noticing obviously wrong or entirely missing SMART data in any drive I've recently tested. I'm curious what your SSD is and just how old it is, if it isn't giving you any SMART information. (Maybe you need to run `smartctl -s on` before it'll show you the stats it has probably been tracking all along?)
- mehrdadn 6y agoAh I see. It's a PM981, from late 2017. Interestingly, the GSmartControl GUI says it doesn't support SMART. But now that I try smartctl -a, I see a bit of information, though not much. The only things regarding failures seem to be "Media and Data Integrity Errors" and "Error Information Log Entries" (which I'm not really sure how to interpret in terms of what's too high and what's too low). Other stuff is just temperature and other statistics. Not sure if I'm supposed to be seeing more, but I feel like hard disks used to report more than this!
- wtallis 6y agoNVMe SSDs report a somewhat different set of indicators than SATA drives. If you want to estimate your own personal write endurance requirements, then you want to keep track of the line that looks like: Data Units Written: 67,509,873 [34.5 TB] Figure out how much that goes up in a typical day/week/month, and you'll know roughly how much you endurance you need. When your SSD is old and you want to monitor it for signs of impending failure, keep an eye on the lines: Available Spare: 100% Available Spare Threshold: 10% [...] Media and Data Integrity Errors: 0 (Quoted stats taken from the 512GB PM981 I borrowed to test. It was barely used at the time.)
- mehrdadn 6y agoAh I see, thank you, that makes sense. Sadly it seems this model doesn't publish an endurance specification at all, so it's hard to tell how close I am to its end of life. Interestingly mine actually already has some errors: Available Spare: 100% Available Spare Threshold: 10% Media and Data Integrity Errors: 10 Error Information Log Entries: 735 but I guess that's probably normal? A least unless it fails suddenly/catastrophically.