Parallella Community

Hey, thank you very much. I would say the same about the device itself! Very nice. I am considering that it may be possible to lower the current requirements even further by making a bitstream without the usb and mmc chunks included, as, like the hdmi, I am not using them. Do you have an opinion on that? It occurred to me that perhaps those features are implemented in the ARM cores, and are not something easily pulled out. Of course, I have not yet had the opportunity to sit and look at the code related to the bitstream. What do you think?

Power consumption is THE critical factor for my applications, as we are running our nodes solely from solar power. With a hard budget of Watt/hours in place, every milliamp makes a difference on the size of the solar array and battery bank. The present setup uses about 25W continuously, but I have not tested under full load yet; full load defined in my mind as processes migrated across all 4 nodes, running all cores in the Epiphany at full.

Would you mind recommending something from the suite of test applications that will place such a load on the network, so I may observe my ammeter and log results? I want to drive it as hard as possible:) With those numbers in hand, a dedicated 5 9's solar power system can be designed... maybe fitted or tailored is a better term.

The setup consuming 25W includes a Cubieboard A10 as console, 4 Parallella nodes, an 8 port highly efficient gigabit switch from Asus, two 12V case fans, and the overhead from a DC-DC converter which regulates 5VDC and 12VDC.
If I shave off a total of 1 or 2 watts across 4 nodes with the diskless booting, its worth it, and even better if no usb or mmc saves a bit more;)

Thanks again!

Brilliant +1

This is ideal for my pair of 7010 Pa's which I run headless. Working on that now!!

I too would be interested in removal of the USB logic from the FPGA for true 'headless' operation (maybe the 'headless' build already does - pls confirm?)
But just how much would it help? I know that there is a reduction of (only) 1-2 degrees when running the 'headless' version. I believe that the HDMI and USB chips on my 7010 boards still use some residual power even though they are not connected. Way back, someone showed a heat picture of the early board which showed USB was also 'warm'.
Note that the actually removes the HDMI and USB chips from the board so I have to assume that there will be a separate build to go along with the 'headless' build for this server version (i.e. renamed "headandusbless" maybe?). Maybe these are better suited to your solar application.

Cheers,