AgentSkillsCN

NestJS Performance

采用 Fastify 适配器、作用域管理以及压缩优化的规范。

SKILL.md
--- frontmatter
name: NestJS Performance
description: Fastify adapter, Scope management, and Compression.
metadata:
  labels: [nestjs, performance, fastify]
  triggers:
    files: ['main.ts']
    keywords: [FastifyAdapter, compression, SINGLETON, REQUEST scope]

Performance Tuning

Priority: P1 (OPERATIONAL)

High-performance patterns and optimization techniques for NestJS applications.

  • •

    Adapter: Use FastifyAdapter instead of Express (2x throughput).

  • •

    Compression: Enable Gzip/Brotli compression.

    typescript
    // main.ts
app.use(compression());
  • •

    Keep-Alive: Configure http.Agent keep-alive settings to reuse TCP connections for upstream services.

Scope & Dependency Injection

  • •Default Scope: Adhere to SINGLETON scope (default).
  • •Request Scope: AVOID REQUEST scope unless absolutely necessary.
    • •Pro Tip: A single request-scoped service makes its entire injection chain request-scoped.
    • •Solution: Use Durable Providers (durable: true) for multi-tenancy.
  • •Lazy Loading: Use LazyModuleLoader for heavyweight modules (e.g., Admin panels).

Caching Strategy

  • •Application Cache: Use @nestjs/cache-manager for computation results.
    • •Deep Dive: See Caching & Redis for L1/L2 strategies and Invalidation patterns.
  • •HTTP Cache: Set Cache-Control headers for client-side caching (CDN/Browser).
  • •Distributed: In microservices, use Redis store, not memory store.

Queues & Async Processing

  • •Offloading: Never block the HTTP request for long-running tasks (Emails, Reports, webhooks).
  • •Tool: Use @nestjs/bull (BullMQ) or RabbitMQ (@nestjs/microservices).
    • •Pattern: Producer (Controller) -> Queue -> Consumer (Processor).

Serialization

  • •Warning: class-transformer is CPU expensive.
  • •Optimization: For high-throughput READ endpoints, consider manual mapping or using fast-json-stringify (built-in fastify serialization) instead of interceptors.

Database Tuning

  • •Projections: Always use select: [] to fetch only needed columns.
  • •N+1: Prevent N+1 queries by using relations carefully or DataLoader for Graph/Field resolvers.
  • •Connection Pooling: Configure pool size (e.g., pool: { min: 2, max: 10 }) in config to match DB limits.

Profiling & Scaling

  • •Offloading: Move CPU-heavy tasks (Image processing, Crypto) to worker_threads.
  • •Clustering: For non-containerized environments, use ClusterModule to utilize all CPU cores. In K8s, prefer ReplicaSets.