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

  • From: Pär Crusefalk <per@xxxxxxxxxxxx>
  • To: pskmail@xxxxxxxxxxxxx
  • Date: Fri, 29 Aug 2014 10:01:21 +0200


I did have the Pi run a minecraft server for the kids prior to making it
run pskmail.
Minecraft can be quite demanding, it certainly is very demanding when
many players are using the server and so I overclocked it.
By looking at the blog entry about that I was quite happy to do some
overclocking as it should be perfectly fine to do so:
The raspberry will reduce the speed if it should get too hot, mine is
not hot at all but I have applied all the heat sinks that are available
for it.

Yesterday I put a new PSU there that did not QRM as much as the old and
decided to launch the server again.
Sadly I can now not launch fldigi as it dies complaining it could not
find /proc/cpuinfo. I recompiled fldigi but had the same issue so
something has happened to it. Perhaps some other upgrade has affected
it. I will try to get some time to make it work again this weekend. When
I did have it running it did not consume very much cpu, not even when
doing PSKR.

73, Per

John Douyere skrev 2014-08-29 03:31:
> 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

Other related posts: