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Joined 1 year ago
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Cake day: June 2nd, 2023

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  • You’ve made me uncertain if I’ve somehow never noticed this before, so I gave it a shot. I’ve been dd-ing /dev/random onto one of those drives for the last 20 minutes and the transfer rate has only dropped by about 4MB/s since I started, which is about the kind of slowdown I would expect as the drive head gets closer to the center of the platter.

    EDIT: I’ve now been doing 1.2GB/s onto an 8 drive RAID0 (8x 600GB 15k SAS Seagates) for over 10 minutes with no noticable slowdown. That comes out to 150MB/s per drive, and these drives are from 2014 or 2015. If you’re only getting 60MB/s on a modern non-SMR HDD, especially something as dense as an 18TB drive, you’ve either configured something wrong or your hardware is broken.


  • This is for very long sustained writes, like 40TiB at a time. I can’t say I’ve ever noticed any slowdown, but I’ll keep a closer eye on it next time I do another huge copy. I’ve also never seen any kind of noticeable slowdown on my 4 8TB SATA WD golds, although they only get to about 150MB/s each.

    EDIT: The effect would be obvious pretty fast at even moderate write speeds, I’ve never seen a drive with more than a GB of cache. My 16TB drives have 256MB, and the 8TB drives only 64MB of cache.




  • I’ve spent the last year or so trying to get myself to not jump out of my pants every time I see one of these things. Then roughly a month ago, I get up at 2am to take a piss, and as I’m opening the door this little fucker falls down no more than 10cm away from my face, lands right on my foot and would have probably run up my pyjamas if I hadn’t managed to reflexively kick and launch it flying across the room. I think it must have been either sitting on top of the door or been trying to climb through the doorframe just as I opened it. Pretty sure I woke up everyone in the house, and probably the neighbors too.

    Anyway, my phobia of these little shits is now 100 times worse than it was.


  • Because none of that unused land is set up to allow a machine to easily roll over it and automatically place/replace/clean the panels. Putting panels between the tracks means you get that for free, as the tracks are there anyway, and are already have electrical infrastructure all along their length.

    The point of the experiment is to see if those benefits end up outweighing the presumably higher chance of panels getting damaged. In the worst case it ends up not being worth while and there isn’t a huge loss, in the best case we end up being able to add a bunch of additional solar capacity without having to build much new infrastructure or cover any previously unused land.

    And it would be trivially easy to have a train run over the tracks to clean the panels, there are already trains which use compressed air/sandblasters/lasers to remove leaves and stuff from the rails. Just add a few more compressed air nozzles in between and boom, all your panels are now clean.