gbozo/no-sdr v2.6.0

v2.6.0 — Backend Performance

on GitHub

Backend Performance

Codec

• opus-lo quality tier (16k mono / 32k stereo) — for AM/NFM voice clients
• 60ms Opus frames (was 20ms) — 3× fewer encoder calls per second
• Opus complexity defaults to 5 (was 10) — ~30% encode CPU reduction with no audible difference at ≤64kbps
• Opus complexity now configurable via Admin → General → DSP & History
• Fix Close() race panic: buffers no longer zeroed on pipeline close; concurrent Process() calls finish safely

Hot path allocations

• Zero-alloc IQ client snapshot — reuse per-dongle scratch slice instead of allocating []cpEntry on every IQ chunk (~50Hz × N dongles)
• Single-alloc FFT broadcast — EncodeMessage/EncodeMessageFloor write type byte + header + deflated payload in one make, eliminating the intermediate copy
• EncodePayloadFloor two-alloc pattern also fixed (was allocating deflated then payload separately)

DSP

• fastLog10Power — replaces math.Log10 per FFT bin with a bitcast + 5-op IEEE 754 polynomial. ~5–12× faster depending on CPU, <0.01 dB error, imperceptible on waterfall
• Incremental PLL phasor — FmStereoDemod no longer calls math.Sin/math.Cos 240,000×/sec per WFM client. Running (sin φ, cos φ) phasor rotated by 5th-order Taylor step; renorms every 1000 samples. Eliminates the dominant CPU cost for WFM on x86
• Batch FIR processing — simpleFir gains processBatch(); FmStereoDemod.Process restructured into two passes with batch FIR between them, enabling compiler auto-vectorization of the 51-tap × 240kHz inner loop

Stats / GC

• Removed runtime.ReadMemStats stop-the-world pause from the 2-second stats loop; replaced with syscall.Getrusage RSS (zero allocation, no GC pause). Platform-aware: bytes on Darwin, kilobytes on Linux

Build

• GOAMD64=v3 added to both Dockerfiles — targets AVX2 (Intel Haswell 2013+, AMD Ryzen 1000+), enabling 8-wide float32 SIMD for FIR/FFT loops without native-only portability issues
• New build:go:native / build:go:opus:native / build:go:full:native npm scripts use GOAMD64=v3 for local builds
• GitHub Actions workflow unchanged — GOAMD64=v3 flows from Dockerfile automatically

Admin UI

• Music ID API keys (AudD / ACRCloud) now use type=text + autocomplete=off — prevents browser password autofill on the General config page
• Admin password field uses autocomplete=new-password
• opusComplexity correctly populated when reopening admin page (was missing from loadServerConfig mapping)