• Korhaka@sopuli.xyz
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    15 days ago

    I wonder how this impacts LVMs, just setup a 2x512GB SSD LVM and plan to add another 500GB SSD to it soon.

    But tbh as long as it beats HDD write speeds it’s probably good enough for the most part. Hard to properly test as my most recent large data transfer on it was with game files and many tiny files are always going to be slower.

    • squaresinger@lemmy.world
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      14 days ago

      It affects them just as much, since LVMs still run on the hardware, so anything on hardware layer will affect the LVM too.

      First, this is mostly only for write speeds. Read speeds aren’t really affected by this.

      So if your 2x512GB are close to full, these will be much slower. If you add a third, that one will be fast. So you’ll still be able to write at about the speed of one drive.

      If you balance the load (which, afaik LVM doesn’t proactively do when you add a new drive), you can get your total speed up by a lot.

      • Korhaka@sopuli.xyz
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        14 days ago

        My thought more was how does an LVM fill each drive? I also filled one drive to like 75% when migrating drives before adding the second. The third hopefully is being added soon. So each isn’t equally filled.

        Never really looked into LVM cache options but perhaps getting a single high performance SSD for that could be an idea. Though it probably doesn’t really matter that much.

        • squaresinger@lemmy.world
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          13 days ago

          That I cannot answer. I’d guess there’s likely something about that in the documentation, but I have never gone that deep on LVM.

      • klankin@piefed.ca
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        14 days ago

        What about something like LVM cache? Would it be worth setting up an X% empty partition on the drive, just for empty space reasons?

        • squaresinger@lemmy.world
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          14 days ago

          Could work. I don’t know how your specific SSD handles partitions. Some SSDs don’t care about partitions on the physical level at all. In that case using a partition or unpartitioned space to reserve space to stay empty would work.

          Some SSDs might actually physically reserve space for a partition, in that case leaving something unpartitioned or as an empty partition wouldn’t help.

          I think most SSDs should ignore the partitions on the physical level, so it should work, but no guarantees.