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Joined 10 months ago
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Cake day: June 3rd, 2025

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  • You could 1000% percent be right here. I don’t have an education on networking or system ops.

    The NAS can sustain gigabit writes without complaint. My premis is the kernel isn’t flushing at wire speed in a steady stream. It hoards 2+ GB in page cache then fires a burst of concurrent NFS RPCs all at once. The NAS can’t ack them fast enough and the client declares it dead.

    I ran three dd tests, same 2GB file, same NAS, only changed client config:

    • 128K buffers: 101 MB/s, dies at 2GB
    • 32K buffers: 2.1 GB/s (all page cache, nothing hitting the wire), dies even harder
    • 64MB dirty page cap: steady 11.4 MB/s, zero timeouts, clean finish

    The NAS handled all 2GB in test 3 because it arrived as a drip instead of a wall.

    At least thats the working theory :)