Slow transfer speeds

  • Hey there,


    I've just set up my first NAS.

    It's a Raspberry Pi 4B with USB HDD.

    The OS and OMV are installed on on the SD card.


    The Pi is plugged into my router (Compal CH7466CE) via Ethernet, as is the client computer.


    I've set up an NFS shared folder and mounted it on my client computer with fstab.

    All seems to be running fine except transfer speeds are much slower than I expected.

    Copying files with rsync shows transfer speeds of ~2.5MB/s. Rsync also updates the progress information very slowly.


    htop shows CPU usage of max 17% on each core (often much lower) on the RPi server.


    What could be the bottleneck here?


    Any help would be really appreciated. Thanks.

  • privacy313

    Added the Label OMV 5.x
  • You have a lot of variables here and you should start by narrowing things down:

    1. How fast can you read files from the USB HDD to the RPi? (dd if=/path/to/large_file_on_usb of=/dev/null status=progress)
    2. How fast is your network? Use netcat to benchmark:
      on client:
      nc -l 1122 > /dev/null
      on RPi:
      dd if=/dev/zero bs=100000 count=1024 | nc <client IP> 1122
    3. If those are fast, then your client might not be able to write very fast
    4. Also, if you try to transfer lots of small files it will always be slower than one large file

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