[pskmail] Re: server on Rasp Pi or Beablebone Black

  • From: Ian Bennett <ibennett@xxxxxxxxxx>
  • To: pskmail@xxxxxxxxxxxxx
  • Date: Fri, 29 Aug 2014 12:08:25 +1000

If you are looking for a bit more CPU grunt, have a look at the Odroid from 
Quad-core at 1.7G with 2G of RAM.
I have a U3 running as a rx-only igate using direwolf. I use multiple instances 
(using different
freqs) to make use of the multiple cores to allow me to cover more of the band.


On 29/08/14 11:31, John Douyere wrote:
> Hi Greg,
> I can't remember saying it was not powerful enough, just that the THOR modes 
> are more demanding that
> most of the other modes.
> If I remember well the discussion thread I was asking if the CPU load was not 
> too high on Raspberry
> PI as the OM could not decode PSKR modes. In the end the issue was not with 
> CPU load but a bug in
> the Fldigi PSKR code.
> The OM also reported that THOR modes could be decoded.
> Having just converted a few Fldigi modems into Android using not the Java 
> language but C++ *natively
> *I have some reasonable idea of the capability of some of these ARM CPUs 
> without the Java overhead.
> For example a rather old HTC Desire phone can decode PSKR, THOR, OLIVIA, MFSK 
> and even MT63 2000L
> without problems. The CPU load does not exceed 50% which leaves enough room 
> for other processes.
> Looking at the results of benchmarks like the Whetstone Native (not Java) 
> benchmark results for
> Raspberry PI on the net I find values of 95 MFLOPS at 700Mhz CPU clock (the 
> default I understand)
> and 134 MFLOPS at 1000Mhz clock speed (over-clocked).
> Compare this to the results of 120 MFLOPS for my HTC desire mentioned above 
> and you can see that it
> is very comparable. So in my opinion it should work on a Raspberry PI, 
> ASSUMING that there no
> significant extra overheads introduced by the GUI side of Fldigi + O/S.
> I don't know what Per has done to make it work in terms of configuration but 
> I would suggest looking
> at the following:
> - Overclock the Raspberry PI to 800-900MHz (Do some research here as it seems 
> to be the maximum
> acceptable long term continuous running overclock limit).
> - In Fldigi:
> 1. Set the slow CPU option ON.
> 2. IN THOR modem disable filtering, soft-symbol and soft-bit decoding.
> 3. In Audio / Settings I would choose either Linear interpolator or Fastest 
> Sinc interpolator.
> - Finally and it can be important on some devices, run Fldigi minimized. This 
> reduces the GUI
> processing quite significantly regardless of the settings of the waterfall.
> Maybe Per can detail his configuration to make it work on the Raspberry PI.
> I believe the Banana PI with it dual core 1GHz ARM-V7 architecture (including 
> hardware floating
> point unit) should provide a much lower CPU load when running Fldigi and a 
> Pskmail server.
> Hope this helps,
> 73, John (VK2ETA)
> On Thu, Aug 28, 2014 at 2:01 AM, Greg <kb1ncj@xxxxxxxxx 
> <mailto:kb1ncj@xxxxxxxxx>> wrote:
>     Greetings Group,
>     I see people mention they are setting up servers with these new micro 
> devices.. I thought I
>     remember when I asked about this maybe a year ago, John (VK) I think said 
> that they were not
>     powerful enough especially with the THOR modes... Still true? I would 
> switch my server out just
>     to save on electric use.
>     Also my server was on boot stuck for a few weeks but back on now..
>     Greg
>     KB1NCJ

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