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It's competition. Every cost cutting tech gets adoption except for boost the main muggle specs like capacity. On the SSD side we have DRAMless and TLC. The an

It's competition. Every cost cutting tech gets adoption except for boost the main muggle specs like capacity. On the SSD side we have DRAMless and TLC. The annoying thing is that unless the government forces disclosure, the honest manufacturers are the ones hurt, having to start advertising "no SMR!" to differentiate, like the organic/health food products in the grocery store that have to list all the poisons they don't have.

segfaultbuserr 7y ago
> On the SSD side we have DRAMless and TLC. I'm happy to buy a DRAMless + TLC SSD for my boot disk on my web browsing PC (not development), it is a reasonable compromise for a lower price. Same for SMR drives, I won't have problems with them as backup disks. I think the problem here is SMR drives are sold without disclosure, and it has already created some serious problems in practice. > What’s worse, they’re shipping DM-SMR drives as “RAID” and “NAS” drives This is causing MAJOR problems – such as the latest iteration of WD REDs (WDx0EFAX replacing WDx0EFRX) being unable to be used for rebuilding RAID[56] or ZFS RAIDZ sets: They rebuiild for a while (1-2 hours), then throw errors and get kicked out of the set.
- deleted 7y ago
  [deleted]
- magicalhippo 7y ago
  > They rebuiild (sic) for a while (1-2 hours), then throw errors and get kicked out of the set. I don't doubt it, but do you have the source for that? I read stories about people using the Seagate Archive disks in RAIDZ and it worked fine for them.
  - cthalupa 7y ago
    Mine completed the rebuild, but it took over 2 weeks vs. the usual 1-2 days my prior WD Red 6TBs had completed in. This has accelerated my move to enterprise 16TB drives, because I really don't want to expose myself to data loss on rebuilds taking hugely extended times.
    - deleted 7y ago
      [deleted]
    - zozbot234 7y ago
      > Mine completed the rebuild, but it took over 2 weeks vs. the usual 1-2 days This also means you'll need a lot more HD's per RAID set to guard against multiple failures during rebuild. Which means that even the supposed data density/space advantage of SMR is moot - you'd be better off with PMR.
  - segfaultbuserr 7y ago
    Source was the article on the HN homepage yesterday, I thought most have seen it, but for those who missed it, here it is. * Western Digital admits 2TB-6TB WD Red NAS drives use shingled magnetic recording https://blocksandfiles.com/2020/04/14/wd-red-nas-drives-shingled-magnetic-recording/ https://blocksandfiles.com/2020/04/14/wd-red-nas-drives-shin...
gruez 7y ago
>On the SSD side we have DRAMless and TLC. Are you sure you're not talking about QLC? Current TLC drives can be pretty decent in terms of write speed and endurance.
- dannyw 7y ago
  Yeah. QLC is bad but mature TLC with a DRAM cache can be an excellent choice b
  - Nursie 7y ago
    QLC with a decent SLC cache seems to work just fine as well, for most consumer purposes - see drives like the sabrent Rocket-Q
    - chx 7y ago
      I do not know whether it's actually possible but if you partitioned an 1TB Intel 660p to only 140GB and left the rest open would it make that into a 140GB SLC SSD? If so, then the 1 USD/GB for an SLC drive is an absolute bargain...
      - wmf 7y ago
        If you can find an SSD with unlimited SLC cache for around 10c/GB and overprovision it by a factor of N then you'd have SLC for 30-40c/GB.
      - gruez 7y ago
        I suspect in terms of actual performance, it's cheaper to get a MLC drive (eg. 970 pro) instead.
    - Dylan16807 7y ago
      QLC with SLC cache is probably the best analogy for these drives, too. Some workloads will never have a problem, others will hit performance walls.
    - 7y ago
LeifCarrotson 7y ago
This, plus the previous post about the WD Red drives, makes it all three manufacturers - there are no honest options left. It's like saying "honest telecoms". Also, "boost the main muggle"? I usually think I know my Potter references, but this one escapes me.
- penguat 7y ago
  Try reading it as "muggle specs" - specifications which the majority of the population will read.
- Tijdreiziger 7y ago
  There are honest telcos - usually cooperatives or foundations rather than for-profit corporations.
userbinator 7y ago
Yes, the NAND flash "decline" (for lack of better words) is sad to see, and it's as you said --- the only marketing spec people seem to care about with storage is capacity. TLC and QLC are misnomers, a TLC cell holds 3 bits but has eight levels and QLC likewise 4 bits with 16 levels. You get a multiplicative increase in capacity for an exponential decrease in reliability. The manufacturers have been very obfuscatory with the marketing, since they know the inconvenient truth. Does anyone still make a reasonably large (>100GB) SSD with good old 100K SLC? I have a 64MB (true 2^26 bytes capacity!) flash drive with 100K SLC; 0 bad blocks when it was new, and still 0 bad blocks a decade and a half later despite plenty of abuse.
- hakfoo 7y ago
  This feels like it could be managed in firmware. It's been well established that many modern SSDs will use a large volume of the NAND in a SLC style mode for performance reasons, and only switch to MLC/TLC/QLC mode as the available space to do so runs down. I would be curious what effect that has on reliability-- if an individual QLC flash cell goes bad, is it still typically usable if you're using psuedo-SLC coding? To go a bit further, I'm amazed you don't see a drive manufacturer offering an enterprise-client "firmware builder" tool, or at least as a build-to-order service if you're a big enough client. I could see customers that wanted to respec their 1TB drives as, say, 750GB to ensure an abundance of over-capacity for reallocation later, or the YOLO "I'm gonna run the cheapest drives in RAID0" crowd slashing overprovisioning and getting 1050Gb out of the same unit. If you dialed down the capacity low enough, the drive could presumably stay in "use SLC mode only" mode for its entire duration.
  - userbinator 7y ago
    The main issue I have with increasingly complex firmware is that it's also a source of bugs; they might not show up in normal usage, but any unusual edge-cases that result in data loss are catastrophic. I'm amazed you don't see a drive manufacturer offering an enterprise-client "firmware builder" tool, or at least as a build-to-order service if you're a big enough client. If they do, you probably wouldn't hear about it --- and I suspect they do, given that there are things like this: https://superuser.com/questions/593303/hitachi-hard-drive-with-apple-firmware-possible-to-install-windows-on https://superuser.com/questions/593303/hitachi-hard-drive-wi...

segfaultbuserr 7y ago

> On the SSD side we have DRAMless and TLC. I'm happy to buy a DRAMless + TLC SSD for my boot disk on my web browsing PC (not development), it is a reasonable compromise for a lower price. Same for SMR drives, I won't have problems with them as backup disks. I think the problem here is SMR drives are sold without disclosure, and it has already created some serious problems in practice. > What’s worse, they’re shipping DM-SMR drives as “RAID” and “NAS” drives This is causing MAJOR problems – such as the latest iteration of WD REDs (WDx0EFAX replacing WDx0EFRX) being unable to be used for rebuilding RAID[56] or ZFS RAIDZ sets: They rebuiild for a while (1-2 hours), then throw errors and get kicked out of the set.

deleted 7y ago
[deleted]
magicalhippo 7y ago
> They rebuiild (sic) for a while (1-2 hours), then throw errors and get kicked out of the set. I don't doubt it, but do you have the source for that? I read stories about people using the Seagate Archive disks in RAIDZ and it worked fine for them.
- cthalupa 7y ago
  Mine completed the rebuild, but it took over 2 weeks vs. the usual 1-2 days my prior WD Red 6TBs had completed in. This has accelerated my move to enterprise 16TB drives, because I really don't want to expose myself to data loss on rebuilds taking hugely extended times.
  - deleted 7y ago
    [deleted]
  - zozbot234 7y ago
    > Mine completed the rebuild, but it took over 2 weeks vs. the usual 1-2 days This also means you'll need a lot more HD's per RAID set to guard against multiple failures during rebuild. Which means that even the supposed data density/space advantage of SMR is moot - you'd be better off with PMR.
- segfaultbuserr 7y ago
  Source was the article on the HN homepage yesterday, I thought most have seen it, but for those who missed it, here it is. * Western Digital admits 2TB-6TB WD Red NAS drives use shingled magnetic recording https://blocksandfiles.com/2020/04/14/wd-red-nas-drives-shingled-magnetic-recording/ https://blocksandfiles.com/2020/04/14/wd-red-nas-drives-shin...

gruez 7y ago

>On the SSD side we have DRAMless and TLC. Are you sure you're not talking about QLC? Current TLC drives can be pretty decent in terms of write speed and endurance.

dannyw 7y ago
Yeah. QLC is bad but mature TLC with a DRAM cache can be an excellent choice b
- Nursie 7y ago
  QLC with a decent SLC cache seems to work just fine as well, for most consumer purposes - see drives like the sabrent Rocket-Q
  - chx 7y ago
    I do not know whether it's actually possible but if you partitioned an 1TB Intel 660p to only 140GB and left the rest open would it make that into a 140GB SLC SSD? If so, then the 1 USD/GB for an SLC drive is an absolute bargain...
    - wmf 7y ago
      If you can find an SSD with unlimited SLC cache for around 10c/GB and overprovision it by a factor of N then you'd have SLC for 30-40c/GB.
    - gruez 7y ago
      I suspect in terms of actual performance, it's cheaper to get a MLC drive (eg. 970 pro) instead.
  - Dylan16807 7y ago
    QLC with SLC cache is probably the best analogy for these drives, too. Some workloads will never have a problem, others will hit performance walls.
  - 7y ago

LeifCarrotson 7y ago

This, plus the previous post about the WD Red drives, makes it all three manufacturers - there are no honest options left. It's like saying "honest telecoms". Also, "boost the main muggle"? I usually think I know my Potter references, but this one escapes me.

penguat 7y ago
Try reading it as "muggle specs" - specifications which the majority of the population will read.
Tijdreiziger 7y ago
There are honest telcos - usually cooperatives or foundations rather than for-profit corporations.

userbinator 7y ago

Yes, the NAND flash "decline" (for lack of better words) is sad to see, and it's as you said --- the only marketing spec people seem to care about with storage is capacity. TLC and QLC are misnomers, a TLC cell holds 3 bits but has eight levels and QLC likewise 4 bits with 16 levels. You get a multiplicative increase in capacity for an exponential decrease in reliability. The manufacturers have been very obfuscatory with the marketing, since they know the inconvenient truth. Does anyone still make a reasonably large (>100GB) SSD with good old 100K SLC? I have a 64MB (true 2^26 bytes capacity!) flash drive with 100K SLC; 0 bad blocks when it was new, and still 0 bad blocks a decade and a half later despite plenty of abuse.

hakfoo 7y ago
This feels like it could be managed in firmware. It's been well established that many modern SSDs will use a large volume of the NAND in a SLC style mode for performance reasons, and only switch to MLC/TLC/QLC mode as the available space to do so runs down. I would be curious what effect that has on reliability-- if an individual QLC flash cell goes bad, is it still typically usable if you're using psuedo-SLC coding? To go a bit further, I'm amazed you don't see a drive manufacturer offering an enterprise-client "firmware builder" tool, or at least as a build-to-order service if you're a big enough client. I could see customers that wanted to respec their 1TB drives as, say, 750GB to ensure an abundance of over-capacity for reallocation later, or the YOLO "I'm gonna run the cheapest drives in RAID0" crowd slashing overprovisioning and getting 1050Gb out of the same unit. If you dialed down the capacity low enough, the drive could presumably stay in "use SLC mode only" mode for its entire duration.
- userbinator 7y ago
  The main issue I have with increasingly complex firmware is that it's also a source of bugs; they might not show up in normal usage, but any unusual edge-cases that result in data loss are catastrophic. I'm amazed you don't see a drive manufacturer offering an enterprise-client "firmware builder" tool, or at least as a build-to-order service if you're a big enough client. If they do, you probably wouldn't hear about it --- and I suspect they do, given that there are things like this: https://superuser.com/questions/593303/hitachi-hard-drive-with-apple-firmware-possible-to-install-windows-on https://superuser.com/questions/593303/hitachi-hard-drive-wi...