I figured since I'm down to the two main time hogs in seti, I should figure out which functions do what to what buffers of data, and in what order.
How long is this buffer's data needed?
Which functions call which...how many loops do they do...etc?
Here is the result...it explains why 'GetFixedPot' and 'analyze_pot' are the main CPU hogs (cache miss hogs really).
analyze_seti
foreach fft/gauss pair
{
if chirp rate ind changes
ChirpData - fills array ChirpedData[]
CalcTrigArray
// Now we will process the just chirped data...
// We will break the entire ChirpedData[] into 'fftlen' chunks and do each one
// as a block
// 1. backward FFT over each block and output to WorkData[]
// 2. compute power spectrum table over fft'ed output, store in PowerSpectrum[CurrentSub]
// 3. if pot freq bin == -1, then try to find spike in PowerSpectrum[]
analyze_pot <- PowerSpectrum[]
// Look for gaussians :: by looping through frequencies * FftLength
GetFixedPoT() <- PowerSpectrum[] --> GaussPoT[]
If fftlen were 1024...then for Frequency=1...GaussPot[] would contain
GaussPoT[0] = spectrum[0]
GaussPoT[1] = spectrum[1024] // cache miss
GaussPoT[2] = spectrum[2048] // ...and so on
frequency = 2
GaussPoT[0] = spectrum[1]
GaussPoT[1] = spectrum[1025]
GaussPoT[2] = spectrum[2049]
GaussFit() <- GaussPoT[]
// Look for pulses :: by looping through frequencies * FftLength
// loop through time for each frequency. PulsePoTNum is used
Build a PulsePoT[] table extracted from the PowerSpectrum[] buffer
(similar to method in GetFixedPot above)
- find_triplets on this PulsePoT[]
- find_pulse(s) on this PulsePoT[]
// end of fft/gauss pair
