• 0 Posts
Joined 1 year ago
Cake day: June 25th, 2023


  • Probably best to look at it as a competitor to a Xeon D system, rather than any full-size server.

    We use a few of the Dell XR4000 at work (https://www.dell.com/en-us/shop/ipovw/poweredge-xr4510c), as they’re small, low power, and able to be mounted in a 2-post comms rack.

    Our CPU of choice there is the Xeon D-2776NT (https://www.intel.com/content/www/us/en/products/sku/226239/intel-xeon-d2776nt-processor-25m-cache-up-to-3-20-ghz/specifications.html), which features 16 cores @ 2.1GHz, 32 PCIe 4.0 lanes, and is rated 117W.

    The ostensibly top of this range 4584PX, also with 16 cores but at double the clock speed, 28 PCIe 5.0 lanes, and 120W seems like it would be a perfectly fine drop-in replacement for that.

    (I will note there is one significant difference that the Xeon does come with a built-in NIC; in this case the 4-port 25Gb “E823-C”, saving you space and PCIe lanes in your system)

    As more PCIe 5.0 expansion options land, I’d expect the need for large quantities of PCIe to diminish somewhat. A 100Gb NIC would only require a x4 port, and even a x8 HBA could push more than 15GB/s. Indeed, if you compare the total possible PCIe throughput of those CPUs, 32x 4.0 is ~63GB/s, while 28x 5.0 gets you ~110GB/s.

    Unfortunately, we’re now at the mercy of what server designs these wind up in. I have to say though, I fully expect it is going to be smaller designs marketed as “edge” compute, like that Dell system.

  • Unfortunately what’s shipping today seems it would offer maybe half that.

    For the batteries that were announced this past week, a larger-than-refrigerator-sized cabinet held a capacity of around 15kWh.

    Around half the energy density by mass of Lithium batteries, and in the order of a sixth of the density by volume.

    Now if only we could come up with a system where your car could be charged while stopped at traffic lights, we might be onto a winner (:

    Considering however that the price of sodium is around 1-2% that of lithium, I expect we will see significant R&D and those numbers quickly start to improve.

  • Without giving Amazon too much of the benefit of the doubt here, I’ve noticed they love to offer you “coupons”, generally with a midnight expiry.

    I expect it’s 100% a tactic to get you to commit to something you’ve looked at a couple of times but might be on the fence about buying.

    I get the same as OP’s logged-out price (nothing hidden) while logged in, perhaps if they are offering a coupon it would take it below the minimum advertised price.

    Definitely stupid, but it’s the only way I can see of arriving at this situation.

  • It can be a one-time setup.

    Right up until your laptop gets its motherboard replaced and won’t boot due to a MOK-signed module (in my case it was ZFS, which I needed for the machine to actually function).

    At which point you

    • Switch secure boot from enforcing to permissive mode (note you can’t turn it off entirely, or the enrollment will fail with an error that your system doesn’t support secure boot).
    • Boot into your OS.
    • Find the arcane command to re-enroll the MOK. That’s sudo mokutil --import /var/lib/shim-signed/mok/MOK.der (for Ubuntu derivatives and probably others), in case someone finds this post in the future.
    • Reboot again, accept enrolling the key.
    • Reboot again, and switch back to enforcing.

    If you have a BIOS password, encrypted filesystem, and all the other moving parts that make having secure boot enabled actually a meaningful exercise, this is neither a fun, nor particularly quick process.

    As for modules being signed automatically when built by DKMS, I’ve never had an issue with that.

  • Since the realistic competitor here is probably magnetic tape, current-generation (LTO9) media can transfer at around 400MB/s, taking 12 hours and change to fill an 18TB tape.

    Earlier archival optical disk formats (https://news.panasonic.com/global/stories/798) claimed 360MB/s, but I believe that is six, double-sided discs writing both sides simultaneously, so 30MB/s per stream. Filling the same six (300GB) discs would take about an hour and a half.

    Building the library to handle and read/write in bulk is always the issue though. The above optical system fit 1.9PB in the space of a server rack (and I didn’t see any options to expand further when that was current technology), and by the looks is 7 units that each can be writing a set of discs (call that 2.5GB/s total).

    In the same single rack you’d fit 560 LTO tapes (10.1PB for LTO9) and 21 drives (8.4GB/s).

    So they have a bit of catching up to do, especially with LTO10 (due in the next year or so) doubling the capacity and further increasing the throughput.

    There’s also the small matter that every one of these massive increases in optical disc capacity in recent years has turned out to be vapourware. I mean I don’t doubt that they will achieve it someday, but they always seem to go nowhere.

  • From the video description:

    I have been a Samsung product user for many years, and I don’t plan to stop anytime soon

    And all sympathy I had for this person just vanished. If you don’t demand better, they will keep doing - and getting away with - shit like this.

    Voting with your wallet might be the one voice you have left in this world, what a way to squander it by continuing to buy products from companies whose representatives behave in this manner.