Mathematically Lossless Compression vs. Lossy Swinging Door
Traditional historians discard raw sensor readings using lossy CompDev swinging-door straight-line approximations—risking concealed thermal spikes or blunted chromatography UV280 peaks during GMP batch review. GxPHistorian applies Stage 1 Exception Deadband filtering (ExcDev/ExcMax) at the edge and archives every emitted sample losslessly in ClickHouse using DoubleDelta + Gorilla + ZSTD(1) at 1.5–2.5 bytes/sample.