HarmonyOS 5 模型瘦身验证:从200MB到5MB的剪枝后准确率回归测试

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以下为 ​​HarmonyOS 5模型剪枝压缩后准确率验证方案​​,包含剪枝策略验证、精度回归测试和性能对比的完整代码实现:


1. 测试架构设计

image.png


2. 模型剪枝验证

2.1 结构化剪枝验证

# pruning-validator.py
import tensorflow as tf
from tensorflow_model_optimization.sparsity import keras as sparsity

def verify_pruning(model_path: str, target_sparsity: float) -> bool:
    model = tf.keras.models.load_model(model_path)
    pruning_summary = sparsity.pruning_summary(model)
    
    # 验证各层稀疏度达标
    for layer in pruning_summary.layers:
        if not layer.sparsity >= target_sparsity * 0.9:  # 允许10%误差
            return False
    
    # 验证模型大小缩减
    original_size = os.path.getsize(model_path)
    pruned_size = len(tf.keras.models.save_model(model, 'temp.h5'))
    return pruned_size <= original_size * (1 - target_sparsity)

2.2 量化后模型校验

// quant-validator.ets
class QuantizationValidator {
  static async verify(model: Model, originalSize: number): Promise<boolean> {
    const quantized = await Quantizer.quantize(model, {
      type: 'int8',
      calibrationData: await DataLoader.load('calibration-set')
    });
    
    const currentSize = ModelAnalyzer.getSize(quantized);
    const accuracyDrop = await this.testAccuracyDrop(model, quantized);
    
    return currentSize <= originalSize * 0.25 &&  // 至少压缩75%
           accuracyDrop < 0.03;                   // 精度损失<3%
  }

  private static async testAccuracyDrop(original: Model, quantized: Model) {
    const [origAcc, quantAcc] = await Promise.all([
      AccuracyTester.test(original),
      AccuracyTester.test(quantized)
    ]);
    return origAcc - quantAcc;
  }
}

3. 精度回归测试

3.1 黄金数据集测试

// golden-test.ets
class GoldenTest {
  static async run(model: Model): Promise<TestResult> {
    const { inputs, outputs } = await GoldenDataset.load(model.name);
    const predictions = await ModelRunner.batchPredict(model, inputs);
    
    return {
      accuracy: this.calculateAccuracy(predictions, outputs),
      cosineSimilarity: this.calculateSimilarity(predictions, outputs)
    };
  }

  private static calculateAccuracy(preds: Tensor, labels: Tensor): number {
    const correct = tf.equal(tf.argMax(preds, 1), tf.argMax(labels, 1));
    return tf.mean(tf.cast(correct, 'float32')).dataSync()[0];
  }
}

3.2 逐层特征对比

// layer-comparison.ets
class LayerwiseComparator {
  static async compare(original: Model, pruned: Model, input: Tensor) {
    const origFeatures = await FeatureExtractor.extractAllLayers(original, input);
    const prunedFeatures = await FeatureExtractor.extractAllLayers(pruned, input);
    
    return origFeatures.map((feat, i) => ({
      layerName: feat.layerName,
      similarity: cosineSimilarity(feat.output, prunedFeatures[i].output)
    }));
  }
}

4. 性能基准测试

4.1 推理速度对比

// speed-benchmark.ets
class InferenceBenchmark {
  static async compare(original: Model, compressed: Model): Promise<BenchmarkResult> {
    const testData = await DataLoader.loadTestSet();
    
    const [origTime, compressedTime] = await Promise.all([
      this.measureInferenceTime(original, testData),
      this.measureInferenceTime(compressed, testData)
    ]);
    
    return {
      original: origTime,
      compressed: compressedTime,
      speedup: origTime / compressedTime
    };
  }

  private static async measureInferenceTime(model: Model, data: Tensor[]): Promise<number> {
    const start = performance.now();
    await Promise.all(data.map(input => ModelRunner.predict(model, input)));
    return performance.now() - start;
  }
}

4.2 内存占用分析

// memory-profiler.ets
class MemoryProfiler {
  static async profile(model: Model): Promise<MemoryUsage> {
    const before = DeviceMemory.getUsage();
    await ModelRunner.warmUp(model);
    const peak = DeviceMemory.getPeakUsage();
    const after = DeviceMemory.getUsage();
    
    return {
      baseline: before.model,
      peakUsage: peak - before.system,
      leak: after.model - before.model
    };
  }
}

5. 剪枝效果验证

5.1 模型结构检查

// model-inspector.ets
class ModelInspector {
  static verifyPruningRate(model: Model, targetRate: number): boolean {
    const layerStats = ModelAnalyzer.getLayerStats(model);
    const prunedLayers = layerStats.filter(l => l.sparsity >= targetRate * 0.8);
    return prunedLayers.length / layerStats.length >= 0.9;  // 90%以上层达标
  }
}

5.2 权重分布分析

// weight-analyzer.ets
class WeightAnalyzer {
  static analyzeSparsity(model: Model): SparsityReport {
    const weights = ModelAnalyzer.getWeights(model);
    const zeroCount = weights.filter(w => Math.abs(w) < 1e-6).length;
    
    return {
      totalWeights: weights.length,
      zeroWeights: zeroCount,
      sparsity: zeroCount / weights.length,
      distribution: this.buildHistogram(weights)
    };
  }
}

6. 完整测试流程

6.1 自动化测试套件

// test-suite.ets
describe('模型剪枝验证', () => {
  let originalModel: Model;
  let prunedModel: Model;
  
  beforeAll(async () => {
    originalModel = await ModelLoader.load('original.h5');
    prunedModel = await ModelLoader.load('pruned.h5');
  });

  it('模型大小应缩减至5MB以内', () => {
    expect(ModelAnalyzer.getSize(prunedModel)).toBeLessThan(5 * 1024 * 1024);
  });

  it('精度损失应<5%', async () => {
    const originalAcc = await GoldenTest.run(originalModel);
    const prunedAcc = await GoldenTest.run(prunedModel);
    expect(originalAcc.accuracy - prunedAcc.accuracy).toBeLessThan(0.05);
  });

  it('推理速度应提升2倍以上', async () => {
    const { speedup } = await InferenceBenchmark.compare(originalModel, prunedModel);
    expect(speedup).toBeGreaterThan(2);
  });
});

6.2 剪枝质量报告

// pruning-report.ets
class PruningReport {
  static async generate(original: Model, pruned: Model) {
    const [originalSize, prunedSize] = [
      ModelAnalyzer.getSize(original),
      ModelAnalyzer.getSize(pruned)
    ];
    
    const [originalAcc, prunedAcc] = await Promise.all([
      GoldenTest.run(original),
      GoldenTest.run(pruned)
    ]);
    
    const { speedup } = await InferenceBenchmark.compare(original, pruned);
    const sparsity = WeightAnalyzer.analyzeSparsity(pruned);
    
    return {
      compressionRate: (originalSize - prunedSize) / originalSize,
      accuracyDrop: originalAcc.accuracy - prunedAcc.accuracy,
      speedupRatio: speedup,
      sparsity: sparsity.sparsity,
      layerSimilarities: await LayerwiseComparator.compare(original, pruned)
    };
  }
}

7. 可视化分析工具

7.1 权重分布对比

// weight-visualizer.ets
@Component
struct WeightComparison {
  @Prop original: number[];
  @Prop pruned: number[];
  
  build() {
    Column() {
      LineChart({
        title: '权重分布对比',
        series: [
          { name: '原始', data: this.original },
          { name: '剪枝后', data: this.pruned }
        ]
      })
    }
  }
}

7.2 精度损失热力图

// heatmap-visualizer.ets
@Component
struct AccuracyHeatmap {
  @Prop similarities: LayerSimilarity[];
  
  build() {
    Grid() {
      ForEach(this.similarities, item => {
        GridItem() {
          Text(item.layerName)
          Progress({ 
            value: item.similarity * 100,
            style: { 
              color: this.getColor(item.similarity) 
            }
          })
        }
      })
    }
  }
  
  private getColor(sim: number): string {
    return sim > 0.9 ? '#00ff00' : 
           sim > 0.7 ? '#ffff00' : '#ff0000';
  }
}

8. 关键验证指标

指标目标值测量工具
模型大小≤5MBModelAnalyzer
精度损失≤5%GoldenTest
推理加速比≥2xInferenceBenchmark
权重稀疏度≥70%WeightAnalyzer

9. 高级验证场景

9.1 对抗样本鲁棒性

// adversarial-test.ets
class AdversarialTest {
  static async compareRobustness(original: Model, pruned: Model) {
    const attacks = ['FGSM', 'PGD', 'CW'];
    const results = [];
    
    for (const attack of attacks) {
      const dataset = await AdversarialLoader.load(attack);
      const [origAcc, prunedAcc] = await Promise.all([
        AccuracyTester.test(original, dataset),
        AccuracyTester.test(pruned, dataset)
      ]);
      
      results.push({
        attack,
        originalAcc,
        prunedAcc,
        drop: origAcc - prunedAcc
      });
    }
    
    return results;
  }
}

9.2 边缘设备部署测试

// edge-deployment.ets
class EdgeDeployTest {
  static async testOnDevice(model: Model) {
    const devices = await EdgeDeviceManager.getDevices();
    const results = [];
    
    for (const device of devices) {
      const result = await device.deployAndTest(model);
      results.push({
        device: device.model,
        fps: result.fps,
        memory: result.memoryUsage,
        temperature: result.maxTemp
      });
    }
    
    return results;
  }
}

10. 完整工作流示例

10.1 模型压缩验证

// compression-workflow.ets
async function validateModelCompression() {
  // 1. 加载原始模型
  const original = await ModelLoader.load('original.h5');
  
  // 2. 执行剪枝
  const pruned = await Pruner.prune(original, {
    targetSparsity: 0.8,
    preserveAccuracy: true
  });
  
  // 3. 量化压缩
  const quantized = await Quantizer.quantize(pruned);
  
  // 4. 运行测试套件
  const report = await PruningReport.generate(original, quantized);
  
  // 5. 生成可视化报告
  ReportVisualizer.show(report);
  
  return {
    passed: report.accuracyDrop < 0.05 &&
            report.compressionRate >= 0.95,
    report
  };
}

10.2 CI/CD集成

# .github/workflows/model-test.yml
jobs:
  pruning-validation:
    runs-on: harmonyos-latest
    steps:
      - uses: harmonyos/model-compression-test@v1
        with:
          original_model: models/original.h5
          target_size: 5MB
          accuracy_threshold: 0.95
      - name: Upload Report
        uses: actions/upload-artifact@v3
        with:
          name: pruning-report
          path: report.html

通过本方案可实现:

  1. ​95%+​​ 模型体积压缩
  2. ​可验证​​ 的精度损失控制
  3. ​多维度​​ 性能对比
  4. ​自动化​​ 部署验证