What are Vite's performance optimization strategies? How to improve build speed?

Vite provides various performance optimization strategies to help developers improve project build and runtime performance. Here are the key methods for Vite performance optimization:

Dependency Pre-bundling Optimization:

1. Reasonable optimizeDeps Configuration:

javascript
export default {
  optimizeDeps: {
    include: ['lodash'], // Force pre-bundling
    exclude: ['some-large-lib'] // Exclude large libraries
  }
}

1. Use Caching: Vite caches pre-bundling results to avoid repeated builds

Build Optimization:

1. Code Splitting:

javascript
export default {
  build: {
    rollupOptions: {
      output: {
        manualChunks: {
          vendor: ['react', 'react-dom'],
          utils: ['lodash', 'axios']
        }
      }
    }
  }
}

1. Tree-shaking: Vite automatically removes unused code

2. Minification Optimization:

javascript
export default {
  build: {
    minify: 'terser', // or 'esbuild'
    terserOptions: {
      compress: {
        drop_console: true // Remove console
      }
    }
  }
}

Development Environment Optimization:

1. Disable Source Maps:

javascript
export default {
  build: {
    sourcemap: false
  }
}

1. Reduce File Watching:

javascript
export default {
  server: {
    watch: {
      ignored: ['**/node_modules/**', '**/.git/**']
    }
  }
}

Asset Optimization:

1. Adjust Inline Threshold:

javascript
export default {
  build: {
    assetsInlineLimit: 4096 // Inline assets smaller than 4KB
  }
}

1. Use CDN: Put large dependencies on CDN

2. Image Optimization: Use modern formats like WebP

CSS Optimization:

1. CSS Code Splitting: Vite automatically extracts CSS to independent files

2. CSS Minification:

javascript
export default {
  build: {
    cssCodeSplit: true,
    cssMinify: 'lightningcss' // Faster CSS minification
  }
}

Plugin Optimization:

1. Load Plugins on Demand: Only load plugins when needed

2. Use Lightweight Plugins: Choose better-performing alternatives

Caching Strategy:

1. Filename Hash: Use [hash] for long-term caching

2. HTTP Caching: Configure server caching strategy

Performance Monitoring:

1. Build Analysis:

bash
npm run build -- --mode analyze

1. Use rollup-plugin-visualizer to analyze build results

Best Practices:

1. Avoid over-optimization, analyze bottlenecks first
2. Use the latest Vite version
3. Configure reasonably, avoid unnecessary optimizations
4. Regularly review dependencies, remove unused packages
5. Use CDN to accelerate static assets