Caching

Lessons

• Profiling and Caching · PHP 8: Modern PHP Development
  Find bottlenecks with profilers and speed up apps with APCu, Redis and HTTP caching.
• Caching with Spring's Cache Abstraction · Spring Boot: From Basics to Production
  Cache expensive reads with @Cacheable and Redis or Caffeine.
• Cache-Aside, Read-Through and Write Patterns · Caching and Performance Engineering
  The standard patterns for reading and writing cached data.
• The Caching Layers of a Web System · Caching and Performance Engineering
  Browser, CDN, reverse proxy, application and database caches — and what belongs where.
• HTTP Caching and CDNs · Caching and Performance Engineering
  Cache-Control, ETags and edge caching for pages and APIs.
• Cache Invalidation and Stampede Protection · Caching and Performance Engineering
  Keep caches correct and protect the database when hot keys expire.
• Redis in Practice · Caching and Performance Engineering
  Data structures, eviction, persistence and pitfalls of running Redis as a cache.
• Persisted Queries, Trusted Documents and HTTP Caching · GraphQL in Production
  Smaller requests, CDN caching and an allowlist of operations.
• Conditional Requests, ETags and Optimistic Concurrency · REST APIs in Depth
  Prevent lost updates and save bandwidth with validators.
• HTTP Caching for APIs · REST APIs in Depth
  Cache-Control, private vs shared caches, CDNs and stale-while-revalidate for API responses.
• Cost Control: Prompt Caching, Routing & Budgets · Integrating LLM APIs
  Pay for fewer tokens and cheaper tokens.
• Caching for Resilience · Resilience Patterns
  Serve stale data instead of errors when origins fail.
• Cache-Aside in Practice · Database Caching at Scale
  The read path, the write path and the details (keys, TTLs, serialization, failures) that decide whether a cache helps or hurts.
• The Stale-Set Race · Database Caching at Scale
  Why cache-aside can still cache an old value forever after a delete — and how leases, versions and short TTLs fix it.
• Cache Avalanches and Cold Starts · Database Caching at Scale
  When the whole cache disappears at once — restarts, failovers, flushes — the database must not take the full load.
• Cache Stampedes (Dogpiles) · Database Caching at Scale
  When a hot key expires, every request misses at once: request coalescing, locks, early refresh and stale-while-revalidate.
• Event-Driven Invalidation with Outbox and CDC · Database Caching at Scale
  Move invalidation out of request handlers so every writer — including scripts and other services — keeps caches correct.
• Two-Tier Caching: In-Process L1 + Redis L2 · Database Caching at Scale
  Microsecond reads from local memory without serving stale data for long: invalidation fan-out with pub/sub.
• Cache Failover and Lost Invalidations · Database Caching at Scale
  Asynchronous Redis replication means a failover can bring back values you already deleted.

Decision guides

• Cache-Aside vs Read-Through vs Write-Through vs Write-Behind
• Rate-Limit Algorithms Compared
• Scaling Reads: Cache, Replicas or Read Models?
• TTL vs Delete-on-Write vs Event-Driven Invalidation
• Where to Store Idempotency Keys

Cookbook recipes

• Cache expensive queries with Redis in PHP · PHP
• Implement rate limiting in a PHP API · PHP
• Rate limit a Spring Boot API with Redis · Spring Boot
• Rate limit FastAPI endpoints with Redis · FastAPI
• Run background jobs from FastAPI with ARQ · FastAPI
• Cache FastAPI responses in Redis · FastAPI
• Build a WebSocket chat endpoint in FastAPI · FastAPI
• Revalidate cached data with tags after a mutation · Next.js
• Rate limit Route Handlers and Server Actions · Next.js
• Pre-render dynamic pages with generateStaticParams and ISR · Next.js
• Rate limit an Express API across instances · Node.js
• Process background jobs with BullMQ · Node.js

Interview questions

Caching interview questions and answers →