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RE: [linrad] FFT performance



Hi Roger,

I can't get to the screen where the values are displayed. This is what is 
happening with details:

$ ./linrad

ADC sampling is set to 8000, 2 channels (I/Q receiver). Parameters are 
saved (W pressed).

At the main screen I press "F" for the hardware test mode. The message
"You are prompted to the parameter selection screens for the following
reason:  par_test file missing". Then at the "Set parameters for mode:
HARDWARE TEST MODE RX CHannels: 1" screen, no matter what values I set,
when I press enter, linrad always tells that "Speed far too slow. Try less
demanding FFT!". That is it. The only way to get out is to press ESC, thus
quiting the application.

So, I'm unable to post the performance values since I cannot get them.

73,

-- Edson, 7n4ncl


On Thu, 14 Nov 2002, W3SZ wrote:

> Hi, Edson!
> 
> How about posting a listing of ALL of your parameters to the list?
> 
> What is your sampling rate?  Did you check out Leif's page on hardware
> performance?
> 
> Its at 
> 
> http://ham.te.hik.se/homepage/sm5bsz/linuxdsp/fft1time/fft1time.htm
> 
> This is what Leif got with a 650 MHz Pentium III:
> 
> SM 5 BSZ - First FFT timing for a large system using Pentium III
> (Coppermine) at 650MHz 
> (Dec 30 2000) 
> ------------------------------------------------------------------------
> --------
>  Sampling rate = 96kHz. 
> No of A/D channels = 4. 
> No of RF channels = 2. 
> Useful bandwidth 2 x 90 kHz. 
> 
> 
> 
>   SIZE = 32768  16 bit no window, bandwidth 1.46Hz
> Vers   Name                    Time
>  0     Radix 2 DIF C           37.15%
>  1     Radix 2 DIF ASM         34.95%
>  2     Twin Radix 2 ASM        41.75%
>  3     Radix 4 DIT C           33.92%
>  4     Twin radix 4 DIT C      33.10%
>  5     Twin radix 4 DIT SIMD   26.10%
> 
>    Typical operation
>   SIZE = 8192  32 bit sin squared window, bandwidth 23Hz
> Vers   Name                    Time
>  0     Radix 2 DIF C           24.01%
>  1     Radix 2 DIF ASM         22.06%
>  2     Twin Radix 2 ASM        20.17%
>  3     Radix 4 DIT C           22.87%
>  4     Twin radix 4 DIT C      19.70%
>  5     Twin radix 4 DIT SIMD   14.70%
> 
>  -------------------------------------
> 
> 
> If we can all see all of  your parameters, maybe we can help.
> 
> 73,
> 
> Roger Rehr
> W3SZ   FN20ah
> 2 Merrymount Road
> Reading, PA  19609-1718
> http://www.qsl.net/w3sz
> 
> 
> 
> > -----Original Message-----
> > From: owner-linrad@xxxxxxxxxxxxxxxxxxxxx 
> > [