2.6 Performance

Performance is

• time required to process something (latency)
• rate at which something is processed (throughput)

Response time = network delay + service time

• response time = client-side latency
• network delay = network latency
• service time = server-side latency

Network latency

• OSI model
• network protocols

Server-side latency

• faster algorithms
• memory versus disk trade-offs
• tread pools and parallel processing
• local cache

Client-side latency

• blocking versus non-blocking I/O
• message formats
• data compression
• CDN
• external cache