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  • MrSpadge - Wednesday, September 23, 2020 - link

    4k model vs. AI model with tuning for reads in parallel to writes: I think the firmware should "simply" detect such conditions and adapt its tuning accordingly. This should not be hard-baked into the drives.
  • PeachNCream - Wednesday, September 23, 2020 - link

    Was excited about 1TB microSD until I read it was QLC. This makes it unsuitable inside of one of those cheap 32-64GB eMMC laptops where you dice up a microSD card into a few partitions under Linux and use it as swap and home directory storage to make the system functional despite the tiny on-board storage capacity.
  • Santos L Halper - Wednesday, September 23, 2020 - link

    Wouldn't the fact that it costs more than most of those cheap laptops preclude it's use in such a laptop? There is only so much you can polish a turd, after all.
  • PeachNCream - Wednesday, September 23, 2020 - link

    Why would that matter? It's removable so it can travel from one laptop to another and isn't exactly a loss once the laptop itself is no longer useful.
  • Santos L Halper - Thursday, September 24, 2020 - link

    Well, given that the 512GB version costs over £100, it stands to reason that this 1TB version will cost at least twice as much. That's an awful lot of money to throw at mildly improving the performance of a mediocre laptop. My point being, surely you'd be better off buying a decent laptop with a proper SSD instead? Each to his own, I suppose 🤷‍♂️
  • antonkochubey - Wednesday, September 23, 2020 - link

    >The WD Purple 1TB microSDXC card is the new capacity flagship in the lineup. Similar to the other microSDXC cards in the WD Purple line, the WD Purple SC QD101 1TB version also utilizes BiCS 4 96-layer 3D NAND flash (TLC-based configuration with 500 p/e cycles).

    Are you sure it's QLC?
  • PeachNCream - Wednesday, September 23, 2020 - link

    I was sure it was QLC, but it looks like the article was updated. TLC is not much better from an endurance perspective though there isn't much any of us can do to get more durable NAND given the way the industry is going these days. We have to simply sit around waiting with our >3000 p/e cycles per cell until better technology becomes cost effective.
  • antonkochubey - Thursday, September 24, 2020 - link

    Well, assuming a 8 mbit/s data rate (and that's higher than usual for a security camera) which is 86.4 GB/day, it'd take you 11 days to re-write the card completely. With 500 p/e cycles at your disposal, that's 5500 days - a bit more than 15 years - until it fails. I'd say that's more than enough.
  • PeachNCream - Thursday, September 24, 2020 - link

    That's assuming writes are spread out evenly across the entire card and that there is no static data that remains stored, preventing writes to those cells with unchanging data.
  • antonkochubey - Thursday, September 24, 2020 - link

    Current gen fancy microSD controllers support wear leveling.
  • Samus - Thursday, September 24, 2020 - link

    512TB seems pretty damn good for endurance...that's literally 30 years of looping 1080p video (4.43Mbps H265 30fps)

    Getting more exotic you could store 6 years of non-stop 4K video recording on one of these before hitting the 512TB endurance rating (18.86Mbps H265 30fps) so its almost impossible to hit the endurance cap in a real world scenario before the warranty is up unless you were to span this as storage across multiple recording streams - something it isn't meant to do.
  • PeachNCream - Thursday, September 24, 2020 - link

    One of the more frustrating things about endurance listed as a total amount of data is that it fails to provide a complete picture of durability. NAND manufacturers don't generally tell the public how many times individual program/erase cycles their flash can tolerate. That's been something quite well hidden since MLC was starting to gain prominence at the same time manufacturing size was shrinking. Modern TLC flash has a difficult time reaching 1K p/e and QLC is generally half of that. Sure you can do some back-o-napkin math and assume that, in a perfect world, a 1TB chunk of NAND can be rewritten 500 times based on the p/e rating if you assume that all cells will evenly soak up write activity, but that typically isn't the case with most storage devices. Wear leveling helps, but is it properly implemented by the device using the NAND in question? Is there data that will persist and not get overwritten?
  • supdawgwtfd - Wednesday, September 23, 2020 - link

    "This allows recording of up to 32 simultaneous video streams"

    At what bitrate???

    32 streams at 128k is worthless...
  • yetanotherhuman - Thursday, September 24, 2020 - link

    You didn't think you'd get actual data from marketing material, did you?

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