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  • linuxgeex - Thursday, July 20, 2023 - link

    QLC has been getting a lot of misplaced hate for the last 3 years. There's been plenty of well engineered QLC products that support at or near 1000 P/E cycles, which was the high tide mark for TLC for a long time. Like any other tool, QLC can be misused. Blaming the tool is a sign of a weak mind. Linus Sebastian gave a great example of that yesterday, lol. The LTT screwdriver can be used as a shiv. Or it can be used to drive screws. How it gets used is up to whoever has it in their hands. Don't blame the tool.
  • 29a - Thursday, July 20, 2023 - link

    I have a 2 TB 660p that is almost 5 years old that's still running strong.
  • bill.rookard - Thursday, July 20, 2023 - link

    I have a Crucial M4 64GB which is currently at 101,390 POH, with 4% of life reported as 'used'. As of now it had one single erase error... Wear leveling count is 134, and 125 power cycles. Pretty durable little SSD.
  • anthony111 - Friday, July 21, 2023 - link

    And that’s a client model, vs this enterprise. Many people also don’t realize that the user can adjust the overprovisioning slider up and down to trade off space for endurance. A modest increase in overprovisioning can easily double endurance.

    One may see, for example, a 1TB 1DWPD drive but an 800GB 3DWPD. They may well be the same hardware with different overprovisioning.
  • ballsystemlord - Friday, July 21, 2023 - link

    I helped another gentlemen who was experiencing problem with his 660p drive. It had ~50% of it's write life span left and it was throwing lots of errors which he'd try to read or write data.

    So although some of you have had great experiences, and certainly write-once ROM is QLC's ideal use case, that doesn't change the fact that these drives have a tendency to be unreliable due to the additional states needed to store data.

    But in general, QLC's main problems are it's slow write rate, once you run out of SLC cache, thus requiring you to way over-provision your storage, and QLC's lack of endurance compared to modern TLC designs which can get >= 1200 TBW per TB of capacity.
  • anthony111 - Friday, July 21, 2023 - link

    Sophistry. The number of Vts impacts endurance not reliability. And 3000 PE cycles here is impressive. Endurance is FUD, and don’t compare enterprise drives to value client SKUs.
  • ballsystemlord - Saturday, July 22, 2023 - link

    By no means is sophistry my goal nor do I understand how you even thought that's what I was doing. Everything I wrote, excluding the poor end-users story can be verified by reading up on SSD info.

    Also, I was responding to the comments above, not making an argument about server SSDs, though certainly QLC is QLC no matter where it is placed.
  • Samus - Friday, July 21, 2023 - link

    Yep. I have installed numerous 670p SSD's as primary\boot drives in dozens of office PC's and NAS's. The most wear I've seen on a QLC SSD was a 665p and it was at 91% still after years of use. Strangely it had over 100TBW and is a 1GB model so it should be closer to 80% but who knows how the wear calculations work it isn't just a fixed estimate based on TBW - it probably factors in reserve area, SLC cache shifting, etc.
  • PeachNCream - Friday, July 21, 2023 - link

    If the life span estimates originate from manufacturer supplied software then there may be something of a bias in presentation of useful remaining durability and algorithmic functionality embedded that plays a bit with the numbers to offer a placebo-like effect to end users prone to bother with installing and running said software. Vendors are well aware that those who would install said software are enthusiasts that are VERY easy to dupe and like little bar graphs and numbers while people with a bit more between the ears are less interested in claims in software for anecdotal individual use cases and more interested in statistical failure rates which are simply not readily available from a credible source across enough QLC products yet. In short, it's a bit too early to tell with most QLC products and there is a lack of data which manufacturers are banking on as the status quo for the foreseeable future while they reap the benefits of people singing single-instance praise which they tend to do more often than make public admissions of their own foolish purchases or data loss resulting from drive failure. Human nature exploited through marketing is powerful and enough people understand how to exploit it while not enough people realise it's happening to them.
  • 29a - Friday, July 21, 2023 - link

    I'm guessing you're one of the people who have been trash talking QLC for the last 5 years.
  • anthony111 - Friday, July 21, 2023 - link

    Yeah, the GP is a lot of vague FUD. I dunno about you but I tend to have actual “single cases” instead of whatever a statistical deployment is. There are certain companies you’ve heard of who buy QLC by the truckload. A bit too early??? QLC has been shipping for 5-6 years, and we’re on 3rd or 4th generation.

    I suspected that this 60TB SKU would have a larger IU just because of physical space for the FTL DRAM. 16KB is way less restrictive than the 64KB IU of the P5316. As an HDD replacement even a bit of space amp on tiny objects is more than compensated for by not having to limit spinners to 8TB and still suffering hotspots.
  • Atom11a - Friday, August 11, 2023 - link

    It's easier to fool people than to convince them that they have been fooled. QLC will never replace TLC. Write speed is abysmal, endurance is crap, and data retention is far worse than TLC, meaning your data will evaporate without you knowing.
  • anthony111 - Friday, July 21, 2023 - link

    99% of SSDs never see more than 15% endurance burn.

    I know of a production QLC object storage deployment that sees 0.01 DWPD. 0.01. Any only needs tens of thousands on IOPS. Solidigm QLC is the holy grail for object storage given the RU density, as much as 3PB raw PER RU.
  • PeachNCream - Saturday, July 22, 2023 - link

    Where did this information originate?

    "99% of SSDs never see more than 15% endurance burn."

    Source please?
  • stanleyipkiss - Thursday, July 20, 2023 - link

    Give me the 60 TB QLC SATA speed 2.5 inch or 3.5 inch SSD for $2000 and I'll buy 10.
  • LiKenun - Thursday, July 20, 2023 - link

    The 30.72 TB SKU is $1,800 on websites that list the new SSDs. The 61.44 TB SKU, which has not been listed anywhere, will probably be double the initially, but come down in price.

    I don’t believe Micron, which has 232-layer NAND, will cap its SSDs to 30.72 TB for much longer. More entrants into the high-density storage space is more than welcome.
  • PixyMisa - Thursday, July 20, 2023 - link

    $60 per TB is not at all bad for this class of drive. Less than two years ago, $100 per TB was entry level.
  • anthony111 - Friday, July 21, 2023 - link

    Moreover, consider the TCO. The cost of the drive BAY not just unit cost per TB. DC RUs. Switches, racks, servers. SNIA’s TCO calculator is terrific for seeing the big picture, especially in the common situation of having to overbuy HDD capacity to get the IOPS you need. SSD $/IOPS >> spinners.

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