What is Performance in software?

Performance in software refers to the measure of how efficiently a system responds to user actions, processes data, and uses resources (CPU, memory, network) under given conditions.

• Response Time -- How fast the system responds to a request
• Throughput -- Number of operations processed per unit of time
• Latency -- Delay between a request and the start of a response
• Resource Utilization -- How efficiently CPU, memory, and network are used

Poor performance directly impacts user experience, conversion rates, and revenue. Studies show that a 1-second delay in page load time can reduce conversions by 7%.

A web application takes 5 seconds to load. After profiling, the team identifies unoptimized database queries and large uncompressed images. By adding indexes and using image compression, they reduce load time to 1.2 seconds, improving user retention by 25%.

• Code profiling and optimization
• Caching strategies (CDN, in-memory, browser)
• Database query optimization
• Lazy loading and code splitting
• Performance monitoring and alerting