Posts by deluxecat

    That one is USB3.0 https://www.ebay.com/itm/112833255553? Says usb3.0 on the cover and there's that blue plug. Also actually tested it.


    But there's a hippo in my bathtub!
    bit flip saved to disk and to backup disk = bit rot (glitches accumulating in movies and music files, slowly worsening over time). Unfortunately, small scale, low wattage, servers with ECC aren't on the market, thus unavailable to purchase, because they didn't promote ECC memory by its practical benefits: Protect music and movies. Just those 4 words.
    Without ECC, then making improvements in network speed and greater storage space actually serves to glitch more files faster (not a real upgrade). So, searching for a real upgrade (to ECC) has been much more intense than simply finding a computer with gigabit onboard.

    This Realtek usb gigabit adapter is compatible and can be found for Less than 7 dollars, even with free shipping.


    In 2018, if a computer didn't come with USB3, Gigabit and error correct ram onboard, then you're not supposed to use it as a file server. However, if one would appreciate misusing the Raspberry Pi twice as fast, this adapter may help. See photo. Previous network configuration at eth0 is notwithstanding because this will be eth1. The upgrade will change the Pi from eleven times slower than a normal file server to only five times slower than a normal file server. Even so, the upgrade could expand the number of simultaneous users from 1 to 3.

    Post#1 may have gone out of date, since Raspbian is currently linux 4.97, armv71, updates twice a week and all of the boards pictured don't have the cpu as the limiting factor. Might be good to have more customers and fair game to brief them on screen with their educational devices.
    Perhaps more importantly,
    I was also fascinated by an idea very much like luakit to localhost for showing OMV on the console screen.

    Regarding performance: In case 'ondemand' should be used I would recommend setting the following also (adding to /etc/rc.local in this case):


    Code
    echo ondemand >/sys/devices/system/cpu/cpu0/cpufreq/scaling_governor 
    sleep 0.1 
    echo 1 >/sys/devices/system/cpu/cpufreq/ondemand/io_is_busy 
    echo 25 >/sys/devices/system/cpu/cpufreq/ondemand/up_threshold 
    echo 10 >/sys/devices/system/cpu/cpufreq/ondemand/sampling_down_factor

    For up-threshold, with some kernels a setting of up to 29 results in the default behavior, so the lowest is 30. I tried setting mine on 1 and discovered the cpu was not changing speed at that low threshold, so I increased it to 2, rebooted and tried again, repeated for a while, and 30 works.


    For sampling_down_factor, it needs to be a long enough duration on high (since last threshold event) so that the speed doesn't go down in the middle of a file transfer. Here's a shortcut: If the sampling rate is 100000 and the throughput of a NanoPi gigabit or faster, then the minimum sampling down factor is 60. That may be enough for holding the speed and power steady so that it doesn't oscillate while writing files.


    So, I think it looks like this
    echo 100000 >/sys/devices/system/cpu/cpufreq/ondemand/sampling_rate
    echo 1 >/sys/devices/system/cpu/cpufreq/ondemand/io_is_busy
    echo 30 >/sys/devices/system/cpu/cpufreq/ondemand/up_threshold
    echo 60 >/sys/devices/system/cpu/cpufreq/ondemand/sampling_down_factor


    That was my guess on a fixed setting that could support all of the different hardware. The greatest difference, of "up to" 5% will be at the target device (arm+usb2+gigabit); however, less than 1% difference to a full scale Xeon file server's throughput.

    So instead of wasting your time with a Raspberry Pi better look for any of the dirt cheap and far better alternatives that allow for almost 40 MB/s (or buy a slightly more expensive ARM board and then enjoy 'PC NAS performance' with a consumption not exceeding that of RPi + external network adapter that much. See this thread for details).

    Good info there! The gigabit equipped NanoPi Neo2 costs even less than a usb gigabit adapter, as well as doing NAS duties at least twice as fast as RPi3 (even 4x faster than a stock-condition RPi3).


    So, that means it is financially advisable to return the RPI3 to its mainstream use as an educational device. Although an exception could be some 150n, 300n, 100mbit networks that run near to the same pace as the RPi3. It also suits my use as a small web server.


    I especially liked your recommend of the Helios4, because that ECC memory could prevent accumulating holes in my photos and mp3 files. Also my i5 file server wastes most of its throughput on waking up; so, instead of a high wattage device that is asleep, I'd much rather have a low wattage device that is awake.


    As far as power-savers go, I've had a wishlist item for a long time: I'd love to have the hard drive scheduled to stay awake during work hours, but allow spindown at night. Is there such a thing as a Spindown Scheduler?

    Working off my list, post 98, here's #2: SD speed.
    There are a few slow defaults, which are from upstream (so not the fault of OMV at all).


    1
    Defaults for the cpu governor aren't scaled to fit the Pi, resulting in the slowest cpu speed. Fortunately, there's a page on the topic. https://obihoernchen.net/1235/…-xu4-with-openmediavault/ Scroll down to CPU governor. The "CPU4" lines aren't needed on the Pi. Values for the Pi are:
    devices/system/cpu/cpu0/cpufreq/ondemand/io_is_busy = 1
    devices/system/cpu/cpu0/cpufreq/ondemand/sampling_down_factor = 120
    devices/system/cpu/cpu0/cpufreq/ondemand/sampling_rate = 100000
    devices/system/cpu/cpu0/cpufreq/ondemand/up_threshold = 30


    2
    The default hard drive cache tuning didn't suit me so I added the following at the end of /etc/sysctl.conf
    vm.dirty_expire_centisecs = 0


    3
    The default SD card reader speed is set on slowest, historically to support cards with now-discontinued specs. https://www.raspberrypi.org/fo…ewtopic.php?f=63&t=140461 Even my worn sandisk can do 80. On the OpenMediaVault image, the usual dtparam=sd_overclock=80 has no effect. Fortunately, the older command does work:
    In /boot/config.txt
    dtoverlay=sdhost,overclock_50=80
    # I actually set mine to 90, but that did require a better SD card.


    4
    Fstab options. It takes a spot of care because a typo could prevent startup.
    for the ext4 defaults,noatime,nodiratime,commit=600
    for the vfat defaults,noatime



    P.S.
    And then last on my list, NTFS: We probably shouldn't use NTFS on linux, but my drive was already full of content. That article https://obihoernchen.net/1235/…-xu4-with-openmediavault/ also has the ntfs mount information. In /etc/fstab, I used this: UUID=driveidhere /mnt/usbhd ntfs-3g rw,auto,user,noatime,async,big_writes,dmask=0000,fmask=0000,uid=1000 0 0
    And also added ntfs ntfs-3g to the prunefs list in /etc/updatedb.conf to prevent indexing of the USB external ntfs hard drive.

    Working off my list, post 98, here's #1: gigabit

    The usb/gigabit adapter is not listed in ifconfig. . .

    First, use the onboard port during a new install, login, at the console, as root, openmediavault, wait for the busy indicator led to stop flashing and the auto restart to occur.


    I have a random realtek gigabit, and it didn't work either. Because, eth1 was not in /etc/network/interfaces.
    Note: for "stretch" or newer distros, issue the command "sudo systemctl enable networking" to bypass dhcpcd before editing /etc/network/interfaces.


    ifconfig write down your router/gateway number
    sudo nano /etc/network/interfaces
    #
    auto lo
    iface lo inet loopback


    allow-hotplug eth0
    iface eth0 inet dhcp


    allow-hotplug eth1
    iface eth1 inet static
    address 192.168.1.250
    network 192.168.1.0
    netmask 255.255.255.0
    broadcast 192.168.1.255
    gateway 192.168.1.1
    dns-nameservers 192.168.1.1


    edit the 3rd digit (x.x.?.x) to match your router
    ctrl-0, ctrl-x, then plug in the gigabit adapter, reboot
    find it at 192.168.?.250 in your web browser, and there the login is admin, openmediavault


    P.S.
    Speed of gigabit to samba shared ramdisk aboard the pi = 40 megabytes per second read and write. <however> The Pi has only 1 internal usb2 hub; and, so, sum total bandwidth (probably 50) is divided by 2 in the case of both ethernet and a hard drive plugged in. When running 2 usb devices simultaneously (hd+gigabit) 25 megabytes per second is theoretically possible; however, what you can expect is 20 megabytes per second nas throughput (as tested with large files).

    On the first try, I obeyed the on-screen instructions and tried to log in with user admin, 17 times. After that I followed the instructions in the Readme on sourceforge, logged in with root, waited 8 minutes for the auto-reboot and it worked perfectly fine, by remote, from the web interface of a different computer (probably what it is supposed to do).


    and some notes
    # Next step, installing the ASIX AX88179 or Realtek USB gigabit is really important for NAS throughput, albeit limited to 40 megaBytes per second on the pi's USB2 (range 17 to 26MB/s if also accessing hard drive).
    # Little tweaks such as SD card to 80, disable usb autosuspend (to keep the drive connected), add io_is_busy to the governor (switch to high speed during io) and disable+powerdown the radios (cool off the pi3), could help incrementally.
    #It may be necessary to manually alter polling settings for individual USB hard drives (if the drive has greatest priority, then write-flush pauses are eliminated).
    # For NTFS3, the tweaks that Synology made, such as enable large block writes, noatime, and disable indexing of ntfs volumes, could make a 4x difference in speed (mainly due to cpu loading difference).