Hi all, so I have about 6 nvme drives in my server, I use them in pairs for download cache, appdata, and vm’s. Would there be a benefit or would it act worse if I combined all 6 drives into one ZFS pool to have the bitrot protection on my VM drives, and the increased storage space.

  • @Nogami
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    12 years ago

    If he had 6 x NVME drives and his controller and MB supported maximizing bandwidth it, it should be capable of 300MB/sec x 6 (1.8TB/sec), parity calculations nonwithstanding because the data is striped across all drives in the pool as it reads and writes to/from all drives in the pool at the same time.

    For example, if a big 1TB file is split across 6 physical devices in ZFS with striping, the system will read pieces of that 1TB from all NVME drives in the pool at the same time, not from one drive at a time.

    Transfer rate is determined by the physical devices (and the hardware attached), not a pool.

    Here’s a little video about it - this isn’t using ZFS, but the idea about increasing transfer rates by raiding your NVMEs together is accurate. He’s getting speeds of over 21TB/sec for reads, and almost 17TB/sec for writes (though his example doesn’t have parity protection, which will boost his speeds)

    https://www.youtube.com/watch?v=DXT1IXFIFAI

    • Red
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      12 years ago

      Oh wow! That’s great info thanks a heap!