Performance terms
Slow software costs money, loses users, and erodes trust. Performance engineering covers profiling, caching strategies, database query optimisation, network latency, memory management, and the architectural patterns that keep systems fast under real-world load. Most performance problems are invisible until they are not — these terms help you find and fix them before your users do.
More on Performance
History
Performance optimization emerged as a distinct discipline in the 1960s–70s as computing resources were scarce and expensive; early work focused on algorithmic efficiency (Big O notation) and compiler optimization. The rise of web applications in the 1990s–2000s shifted focus to network latency, database query efficiency, and caching strategies, driven by real user experience demands. The 2010s saw standardization efforts like Google's Core Web Vitals and widespread adoption of profiling tools, CDNs, and in-memory caches (Redis, Memcached), making performance measurable and addressable at scale. Modern practice integrates continuous monitoring, synthetic benchmarking, and observability platforms to track tail latency and resource consumption across distributed systems. Today, performance is embedded into development workflows as a non-functional requirement, with frameworks and tooling built to optimize by default—from PHP JIT compilation to HTTP/3 and edge computing.
Key concepts
- Time Complexity (Big O)
- Space Complexity
- Database Indexing
- N+1 Query Problem
- Caching Strategies
- HTTP Caching (ETags
- Cache-Control)
- Core Web Vitals
- Profiling & Benchmarking
Best references
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Web Vitals Google's official guidance on Core Web Vitals (LCP, FID, CLS) and their impact on search ranking. Essential reading for understanding modern performance metrics.
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High Performance Browser Networking Ilya Grigorik's comprehensive book covering TCP, TLS, HTTP/1.1, HTTP/2, HTTP/3, and optimization strategies. Authoritative reference for networking fundamentals underlying web performance.
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Redis Documentation Official Redis docs covering data structures, persistence, clustering, and performance patterns. Canonical source for Redis caching and pub/sub strategies.
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PostgreSQL Documentation: Indexes & Query Planning Authoritative reference for database indexing, EXPLAIN query analysis, and index selectivity. Directly applicable to query optimization and covering indexes.
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The Art of Computer Systems Performance Analysis Brendan Gregg's performance analysis methodology and tools reference. Foundation for systematic profiling, tail latency analysis, and flame graphs.
Typed relationships here
Edges touching a Performance term. How edges work →
- Memory Leak Often seen in Batch Processing 16h
- Memory Leak Often seen in Async Processing / Job Queues 1d
- Memory Leak Often seen in PHP-FPM 1d
- Profiling & Benchmarking Detects Memory Leak 1d
- Fuzzy Search Often seen in Full-Text Search 2d
Caching Strategies (APCu, Redis, Memcached)
PHP 5.0+ 
CDN Edge Caching
PHP 5.0+ 
Connection Pooling
PHP 5.0+ 
Covering Index