OMV3 works fine (but slow); OMV4 breaks when disk is accessed from multiple devices

  • I have been running OMV 3 on a Raspberry Pi model B for about 2 years. It has been running great -- very slow throughput, but solid as a rock and more than fast enough for my home NAS needs.


    I recently got a Raspberry Pi 3B+ and decided to upgrade to OMV4. Getting it set up and running was fairly painless, and I was immediately seeing a five-fold increase in throughput (from 2MB/s to 10 MB/s)! BUT, when multiple devices are accessing the device (one downloading and one copying a file, say, or copying a file remotely and doing an rsync --dry-run locally), the throughput drops to 0 after a few seconds and remote devices trying to access get an unexpected network error. I assume that OMV isn't feeding data to the connection for long enough that the network request fails, because retrying always works for a few seconds before failing out again.


    I have read most of @tkaiser's posts (thanks for the info!) on the RaspBerry Pi and know that it is "the worst SBC" for running a NAS. Point taken. However, it's what I have access to. Since the model B (1 core, 512MB ram) works really really well even when I have 7 or 8 devices streaming from it, and the #B+ (4 cores, 1GB ram) seems to choke on multiple streams, I'm assuming that somehow OMV4 has been optimized to pretty much use everything it can get up to a certain point (I realize this could be very wrong, and would love to hear other thoughts). So:


    >>Is it possible in some way to 'cripple' omv 4 so I can keep it's speeds below what the 3B+ can handle (interesting the load never goes past 3 in the performance statistics)?


    >>Am I completely off base and should be looking in a different place for trying to fix this?


    >>Barring that, anyone know where I could find an OMV3 Image for the RaspBerry Pi that works like the omv4 image created by tkaiser? Or should I just try to install it manually through a distribution of Raspbian stretch?


    Thanks!

  • I'm assuming that somehow OMV4 has been optimized to pretty much use everything it can get up to a certain point


    Nope, no optimizations happen on the RPi since the hardware is too crappy.


    All that happens is a task in the background increasing responsiveness of certain filesharing tasks and a global limiting of networking speed to 100 Mbits/sec since Gigabit Ethernet on those thingies is still broken to my knowledge.


    If you want to fiddle around with symptoms you could do a 'crontab -e' or edit /etc/rc.local. Reverting back to OMV3 is weird since the same (non) optimizations happen there. Replace your board with something that works is the better idea.

  • Thanks for the quick response! Interesting to know that the same lack of optimization are in both versions of OMV. I wonder why the 1-core, 512MB board is stable as a rock with release 3 and the 4-core, 1028MB board is so much less stable with OMV4? I'll definitely look at the crontab and rc.local. Thanks for that tip


    I'd love to replace it with a real computer, but I'm living in Africa and it will be months before I'm somewhere where I will have access to reasonably priced options.


    Given my current constraints, do you have any suggestions about the best way to install OMV3 on my PI3B+ to see if it has the same problems? Thanks!

  • do you have any suggestions about the best way to install OMV3 on my PI3B+


    No, since it won't change anything. 2,000 users per months download OMV4 for RPi -- if they would run into the same troubles the forum would be flooded only with Raspberry Pi issues.


    So better analyze what's wrong in your installation instead of trying crude workarounds. Raspberry Pi problem N°1 is underpowering so better check for this first.


    New approach for Raspberry Pi OMV images

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