Index of system design topics

Summaries of various system design topics, including pros and cons. Everything is a trade-off.

Each section contains links to more in-depth resources.

• System design topics: start here
  • Step 1: Review the scalability video lecture
  • Step 2: Review the scalability article
  • Next steps
• Performance vs scalability
• Latency vs throughput
• Availability vs consistency
  • CAP theorem
    • CP - consistency and partition tolerance
    • AP - availability and partition tolerance
• Consistency patterns
  • Weak consistency
  • Eventual consistency
  • Strong consistency
• Availability patterns
  • Fail-over
  • Replication
  • Availability in numbers
• Domain name system
• Content delivery network
  • Push CDNs
  • Pull CDNs
• Load balancer
  • Active-passive
  • Active-active
  • Layer 4 load balancing
  • Layer 7 load balancing
  • Horizontal scaling
• Reverse proxy (web server)
  • Load balancer vs reverse proxy
• Application layer
  • Microservices
  • Service discovery
• Database
  • Relational database management system (RDBMS)
    • Master-slave replication
    • Master-master replication
    • Federation
    • Sharding
    • Denormalization
    • SQL tuning
  • NoSQL
    • Key-value store
    • Document store
    • Wide column store
    • Graph Database
  • SQL or NoSQL
• Cache
  • Client caching
  • CDN caching
  • Web server caching
  • Database caching
  • Application caching
  • Caching at the database query level
  • Caching at the object level
  • When to update the cache
    • Cache-aside
    • Write-through
    • Write-behind (write-back)
    • Refresh-ahead
• Asynchronism
  • Message queues
  • Task queues
  • Back pressure
• Communication
  • Transmission control protocol (TCP)
  • User datagram protocol (UDP)
  • Remote procedure call (RPC)
  • Representational state transfer (REST)
• Security
• Appendix
  • Powers of two table
  • Latency numbers every programmer should know
  • Additional system design interview questions
  • Real world architectures
  • Company architectures
  • Company engineering blogs
• Under development
• Credits
• Contact info
• License