Re: [Discuss-gnuradio] Problems running example audio_fft.py

[Michael Dickens]

> > I know that the GNU Radio GUI stuff is -slow- on OSX because it does
> > wx(Python)->X11->Aqua/CoreGraphics, and the "X11->" part is a big
> > bottleneck.

> Where did you get the above
> information from? Is there some good source for reading about this
> developing good wxpython graphics on os x?

The info came from my old readings of how wxPython worked.  Since I  
wrote that statement, I went back and read through the updated info  
on wxPython for OSX (called wxMac), which states that it's a "native  
Aqua" implementation - so my original statement was not correct.  My  
bad ;)  I certainly don't deny this any longer, though I wonder  
what's going on behind the scenes ... read on.

I just tested this theory out by running "pythonw usrp_wfm_rcv.py -f  
101.7" from a Terminal.app, and without X11 running at all.  It  
works, hence the wxMac stuff isn't directly going through X11 for the  
display.  This is a Gual G4 @ 1.25 GHz, OSX 10.4.8, 1.75 GB DRAM,  
with the following installed by DarwinPorts:

py-wxpython @2.6.1.0_0
python24 @2.4.3_1+darwin_8
wxWidgets @2.6.3_0+darwin_8

> Just to note: I always called my wxpython script direct from the
> terminal with no x11 and still had no visualization in my fftsink.
> Instead, I got just a blank window and the processor was running at
> full.

Here's an interesting statistic:

running "./usrp_wfm_rcv_nogui.py" results in python usage of about  
26% (out of 200%, on my Dual G4 @ 1.25 GHz).
running "pythonw usrp_wfm_rcv.py" results in python usage of about  
120% (out of 200%), along with the winderserver jumping from 0% to  
10% - so almost 100% utilization of 1 of the 2 CPU's to -just- cover  
the GUI part, not to mention anything going on in the background.  If  
I switch out of this window (cover it up with another window), then  
it locks up & I get the SPOD < http://en.wikipedia.org/wiki/ 
Spinning_wait_cursor > and have to force-kill the window.

Hence I would believe that if you're running on a single-cpu G4 or  
G5, even up to 2 GHz, the wxGUI stuff probably won't be very  
effective.  OTOH, running a dual-G4 @ 1.25 GHz -just barely- works,  
so running a Dual-G5 @ 2.0 GHz, or the new Core-Duo's at 2.0 GHz,  
will surely be good enough to get a reasonable display - but nothing  
special compared do the same hardware running Linux.

I would be quite curious about the CPU utilization of a Linux box -  
along with the hardware specs to make the judgement relatively  
correct.  Even better would be to try an Intel Mac running both OSX  
and Linux and compare the CPU utilization ... hmmm ... that would be  
pretty cool so I'll look into it. - MLD