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stickman

espressobin power consumption

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Since I don't have one unit yet and the information related to this board is scarce, I'd like to ask if someone who owns one could test what the power budget for the board is. In Marvell's github wiki there is the following mention:

 

Quote

The innovative and unique architecture ofthe ARMADA 3700 family performs up to 7,000 CoreMarks under 1Watt, delivering unprecedented performance-to-power and performance-to-cost index in the embedded market.

 

It would be really great if under load and with all the network ports connected to gigabit the board only took 1W@12V.

 

I found a script in github that would help to reduce power usage:

 

https://github.com/MarvellEmbeddedProcessors/main/wiki/Power-Saving-Script

 

Thanks for you help. Depending on the results I may have a solution for one project where I need to use a dual-lan board with low power consumption.

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Power consumption of espressobin during the boot process is between 4.5 - 5.0 W.

I am running Armbian on SD - idle power consumption is 3.0 W (ondemand governor).

Consumption rises to 3.6 W while compiling source code using both kernels ...

(Armbian already runs perfectly stable)

root@espressobin:# cat /proc/version
Linux version 4.4.73-mvebu64 (root@devel) (gcc version 5.4.0 20160609 (Ubuntu/Linaro 5.4.0-6ubuntu1~16.04.4) ) #9 SMP PREEMPT Sun Jun 25 22:02:55 CEST 2017

root@espressobin:# cpufreq-info 
cpufrequtils 008: cpufreq-info (C) Dominik Brodowski 2004-2009
Report errors and bugs to cpufreq@vger.kernel.org, please.
analyzing CPU 0:
  driver: cpufreq-dt
  CPUs which run at the same hardware frequency: 0 1
  CPUs which need to have their frequency coordinated by software: 0 1
  maximum transition latency: 50.0 us.
  hardware limits: 200 MHz - 1000 MHz
  available frequency steps: 200 MHz, 250 MHz, 500 MHz, 1000 MHz
  available cpufreq governors: conservative, userspace, powersave, ondemand, performance
  current policy: frequency should be within 200 MHz and 800 MHz.
                  The governor "ondemand" may decide which speed to use
                  within this range.
  current CPU frequency is 250 MHz.
  cpufreq stats: 200 MHz:83.97%, 250 MHz:8.44%, 500 MHz:7.09%, 1000 MHz:0.51%  (998)
analyzing CPU 1:
  driver: cpufreq-dt
  CPUs which run at the same hardware frequency: 0 1
  CPUs which need to have their frequency coordinated by software: 0 1
  maximum transition latency: 50.0 us.
  hardware limits: 200 MHz - 1000 MHz
  available frequency steps: 200 MHz, 250 MHz, 500 MHz, 1000 MHz
  available cpufreq governors: conservative, userspace, powersave, ondemand, performance
  current policy: frequency should be within 200 MHz and 800 MHz.
                  The governor "ondemand" may decide which speed to use
                  within this range.
  current CPU frequency is 250 MHz.
  cpufreq stats: 200 MHz:83.97%, 250 MHz:8.44%, 500 MHz:7.09%, 1000 MHz:0.51%  (998)

 

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On 21/7/2017 at 8:04 PM, lupus said:

Power consumption of espressobin during the boot process is between 4.5 - 5.0 W.

I am running Armbian on SD - idle power consumption is 3.0 W (ondemand governor).

Consumption rises to 3.6 W while compiling source code using both kernels ...

(Armbian already runs perfectly stable)

 

 

Thanks a lot for answering... even though those numbers are quite high (at least for my project they are), could you please test the script I linked to in my post to check if there is any improvement?

 

 

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8 hours ago, stickman said:

could you please test the script I linked to in my post to check if there is any improvement?

The script uses devmem - such a binary is not part of the Ubuntu image. I compiled devmem2 from gitgub sources (https://github.com/pavel-a/devmemX).

The output of the adapted script unfortunately just produced a bunch of segmentation faults ...

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For anyone who wants to test power consumption, I'll recommend not supplying the board with 12V, but instead 5.2V, which is the minimum voltage required by the voltage regulator.

The higher the input voltage, the higher power-loss you'll get.

I recommend a good 5.2V PSU, which provides a heavy current like more than 3A.

You can use a 6V PSU if you can't find anything lower, but just make sure that it can give the board a lot of current.

For keeping power consumption down, I also recommend that you do not use the USB-ports nor the SATA port.

That means booting Linux from the microSD card port - or if you want to cheat, you can supply an external harddisk with power from a different PSU and only connect the SATA data cable to the Espressobin. This will result in that the harddisk's power usage does not influence the measurements of the board itself.

 

-And of course, as Thomas says - it's a very good idea shutting down peripherals you do not use.

 

Unfortunately, there are things you can't change. The board has been sprayed with voltage regulators - even nested!

I'm convinced that the board could have been designed a little better regarding this.

I have not checked if you can shut down some of the power regulators completely, but even if you issue the "poweroff" command, the CPU is still running!!

 

Things to consider:

Powering a SATA drive from the board uses a lot of power. A 3.5" drive use much more than a 2.5" drive (check your drive's specs).

USB devices use lots of power.

MicroSD / MMC uses some power, but it's not extreme.

A Mini-PCIe WiFi card uses a lot of power; I'm fairly convinced that the built-in Gbit Ethernet uses less.

(unfortunately the Topaz switch has not been utilized very well on the board; it's fairly much a waste, it's just using power without giving extra performance).

The DDR RAM uses a fair amount of power, but for good reasons it's not smart to turn it off. ;)

... All those things add on top of the CPU's own power usage, which is said to be 1W.

 

At the moment, I do not have the proper equipment ready for measuring the power usage on the board; but if I find a way, I'll be using a multimeter and a 5.2V power source - and I'll likely be running Armbian from the SD-card or perhaps cheating by running it from a SATA disk with a secondary power supply, so you can easily add your own numbers for the harddisks of your choice.

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