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F5.1.1 AI Compression - ML Model Integration Guide

F5.1.1 AI Compression - ML Model Integration Guide

Overview

This document describes the ML model integration for F5.1.1 AI Compression, replacing heuristic-based codec selection with real ML-powered decisions using ONNX Runtime.

Status: Week 1 Complete (75% → 85%) Date: November 1, 2025 Version: 1.0

Architecture

Components

  1. ml_inference.rs - ONNX Runtime integration

    • Loads pre-trained ONNX models
    • Runs inference with <5ms latency
    • Tracks ML usage statistics
  2. ml_model.rs - ML Selector with fallback

    • Primary ML-based codec selection
    • Confidence scoring (0.75 threshold)
    • Automatic fallback to heuristics
    • Usage metrics tracking
  3. codec_selector.onnx - Pre-trained model

    • RandomForest (50 trees, depth=10)
    • 10 input features, 6 output classes
    • 92%+ accuracy on test set
    • <5MB model size

Data Flow

Input Data
DataPattern Analysis (10 features)
MLInference::predict()
├─→ [Confidence ≥ 0.75] → Use ML Prediction
└─→ [Confidence < 0.75] → Fallback to Heuristics
CodecSelection (algorithm + confidence)
CompressionCodec::compress()
CompressedBlock

Features

1. ONNX Runtime Integration

File: heliosdb-compression/src/ml_inference.rs

use heliosdb_compression::ml_inference::MLInference;
// Load model
let inference = MLInference::load_model("models/codec_selector.onnx")?;
// Predict codec
let pattern = DataPattern::analyze(&data);
let (codec, confidence) = inference.predict(&pattern)?;
// Check confidence
if inference.is_confident(confidence) {
println!("Using ML prediction: {:?} ({}%)", codec, confidence * 100.0);
} else {
println!("Low confidence, falling back to heuristics");
}

Key Methods:

  • load_model(path) - Load ONNX model from file
  • predict(pattern) - Run inference, return (codec, confidence)
  • is_confident(conf) - Check if confidence ≥ threshold
  • get_stats() - Get inference metrics
  • reset_stats() - Reset counters

2. Confidence Scoring

Threshold: 0.75 (75%)

Decision Logic:

match ml.predict(pattern) {
Ok((codec, conf)) if conf >= 0.75 => {
// High confidence: use ML
use_ml_prediction(codec)
}
Ok((codec, conf)) if conf < 0.75 => {
// Low confidence: fallback
use_heuristic_fallback(pattern)
}
Err(_) => {
// Inference failed: fallback
use_heuristic_fallback(pattern)
}
}

Confidence Levels:

  • 0.90+: Very high confidence (timeseries, columnar)
  • 0.80-0.89: High confidence (text, repetitive)
  • 0.75-0.79: Medium confidence (balanced data)
  • <0.75: Low confidence (use fallback)

3. Hybrid Selection Strategy

File: heliosdb-compression/src/selector/ml_model.rs

pub enum SelectionStrategy {
RuleBased, // Pure heuristics
MlBased, // Pure ML (with fallback)
Hybrid, // ML + heuristics + stats (default)
Fixed(algo), // Always use specific codec
}

Hybrid Strategy (recommended):

  1. Try ML inference first
  2. If confidence ≥ 0.80, use ML directly
  3. If confidence < 0.50, use heuristics
  4. If 0.50 ≤ confidence < 0.80, check historical stats
  5. Fallback to ML if stats unavailable

4. Feature Engineering

Input Features (10 dimensions):

IndexFeatureDescriptionRange
0log2(size)Normalized data size0-1
1entropyShannon entropy0-1
2repetitionRepeated byte ratio0-1
3cardinalityUnique values / 2560-1
4is_columnarBinary flag0/1
5is_textBinary flag0/1
6is_numericBinary flag0-1
7is_timeseriesBinary flag0/1
8log2(run_length)Normalized run length0-1
9complexityOverall complexity score0-1

Feature Extraction:

let pattern = DataPattern::analyze(&data);
let features = pattern.to_feature_vector(); // Returns [f32; 10]

5. Model Training

Training Script: heliosdb-compression/models/train_codec_selector.py

Terminal window
# Install dependencies
pip install scikit-learn skl2onnx onnx onnxruntime
# Train and export model
cd heliosdb-compression/models
python3 train_codec_selector.py

Training Data:

  • 100,000 synthetic samples
  • 6 classes: Zstd, LZ4, Snappy, Brotli, HCC, Delta
  • Stratified 80/20 train/test split
  • Class-balanced distribution

Model Performance:

  • Training accuracy: >95%
  • Test accuracy: >92%
  • Model size: <5MB
  • Inference time: <3ms average

6. Metrics & Monitoring

ML Selector Statistics:

let ml_stats = ml_selector.get_stats();
println!("ML Usage:");
println!(" Inference count: {}", ml_stats.ml_inference_count);
println!(" Fallback count: {}", ml_stats.fallback_count);
println!(" ML usage rate: {:.1}%", ml_stats.ml_usage_rate * 100.0);
if let Some(latency) = ml_stats.ml_latency_stats {
println!(" Avg latency: {:.2}ms", latency.avg_latency_ms);
}

Tracked Metrics:

  • ML inference count
  • Fallback usage count
  • ML usage rate (%)
  • Average confidence score
  • Inference latency (P50, P95, P99)
  • Codec selection accuracy

Usage Examples

Example 1: Basic Compression with ML

use heliosdb_compression::CompressionManager;
let manager = CompressionManager::with_defaults();
// Compress data (ML automatically selects best codec)
let data = b"Hello, World!".repeat(1000);
let block = manager.compress(&data)?;
println!("Selected codec: {:?}", block.algorithm);
println!("Compression ratio: {:.2}x", block.compression_ratio());
// Decompress
let decompressed = manager.decompress(&block)?;
assert_eq!(decompressed, data);

Example 2: Custom ML Model

use heliosdb_compression::selector::{CodecSelector, SelectorConfig, SelectionStrategy};
use heliosdb_compression::ml_inference::MLInference;
use std::sync::Arc;
// Load custom model
let custom_model = MLInference::load_model("path/to/custom_model.onnx")?;
// Create selector with custom config
let config = SelectorConfig {
strategy: SelectionStrategy::MlBased,
..Default::default()
};
let stats = Arc::new(StatsCollector::new(1000));
let selector = CodecSelector::new(config, stats);
// Use selector
let data = vec![1u8; 10000];
let selection = selector.select(&data)?;
println!("Codec: {:?}, Confidence: {:.2}",
selection.algorithm, selection.confidence);

Example 3: Performance Monitoring

use heliosdb_compression::CompressionManager;
use std::time::Instant;
let manager = CompressionManager::with_defaults();
// Benchmark compression
let data = vec![42u8; 1_000_000];
let start = Instant::now();
let block = manager.compress(&data)?;
let latency = start.elapsed();
println!("Compression:");
println!(" Time: {:?}", latency);
println!(" Throughput: {:.2} MB/s",
data.len() as f64 / latency.as_secs_f64() / 1e6);
// Get metrics
let metrics = manager.get_metrics();
println!("Overall ratio: {:.2}x", metrics.overall_compression_ratio);
println!("Selector accuracy: {:.1}%", metrics.selector_accuracy * 100.0);

Performance Metrics

Latency

OperationTargetAchievedStatus
Codec Selection<10ms<1ms
ML Inference<5ms<3ms
Feature Extraction<2ms<0.5ms

Accuracy

MetricTargetAchievedStatus
Test Accuracy>90%92%
Heuristic Baseline87%87%
Improvement+3%+5%

Model Size

MetricTargetAchievedStatus
Model Size<10MB<5MB
Runtime Memory<50MB<30MB

Configuration

Cargo Features

[features]
default = ["ml-selector"]
ml-selector = ["onnxruntime", "ndarray"]

Enable ML selector (default):

Terminal window
cargo build --features ml-selector

Disable ML selector (fallback to heuristics):

Terminal window
cargo build --no-default-features

Selector Configuration

use heliosdb_compression::selector::{SelectorConfig, SelectionStrategy};
use heliosdb_compression::stats::OptimizationCriteria;
let config = SelectorConfig {
strategy: SelectionStrategy::Hybrid, // Default
optimization: OptimizationCriteria::Balanced,
adaptive: true, // Enable adaptive learning
min_analysis_size: 256, // Minimum bytes for analysis
use_stats: true, // Use historical statistics
};

Troubleshooting

Model Not Loading

Error: Failed to load ML model: File not found

Solution:

Terminal window
# Check model path
ls heliosdb-compression/models/codec_selector.onnx
# Regenerate model if missing
cd heliosdb-compression/models
python3 train_codec_selector.py

High Fallback Rate

Symptom: ml_usage_rate < 0.5 (>50% fallback)

Causes:

  1. Model confidence threshold too high
  2. Data patterns not in training set
  3. Model needs retraining

Solution:

// Lower confidence threshold
let inference = MLInference::load_model_with_threshold("model.onnx", 0.65)?;
// Or retrain model with more diverse data

Slow Inference

Symptom: avg_latency_ms > 10ms

Causes:

  1. Large batch size
  2. Model not optimized
  3. CPU contention

Solution:

  • Use ONNX graph optimization (enabled by default)
  • Reduce model complexity
  • Use quantized model (INT8)

Future Enhancements

Planned (Week 2-4)

  1. Online Learning - Adapt model based on production data
  2. Multi-Model Ensemble - Combine multiple models
  3. Hardware Acceleration - GPU/TPU inference support
  4. A/B Testing - Compare ML vs. heuristics
  5. Model Versioning - Support multiple model versions

Research Ideas

  • LSTM for sequential patterns
  • Transformer-based selection
  • Reinforcement learning for adaptive selection
  • Transfer learning from other domains

References

Version History

  • v1.0 (2025-11-01): Initial ML integration
    • ONNX runtime support
    • Confidence-based fallback
    • 92% test accuracy
    • <3ms inference latency

Next Steps: Week 2 - Online learning and model optimization