Capacity Planning on Chen Kai Bloghttps://www.chenk.top/en/tags/capacity-planning/Recent content in Capacity Planning on Chen Kai BlogHugoenThu, 10 Jul 2025 09:00:00 +0000System Design (1): Thinking in Systems — Load, Latency, and the Art of Estimationhttps://www.chenk.top/en/system-design/01-thinking-in-systems/Thu, 10 Jul 2025 09:00:00 +0000https://www.chenk.top/en/system-design/01-thinking-in-systems/<p>A friend once asked me to help debug a performance problem. Their photo-sharing app worked fine in development but collapsed under production traffic. The database was melting, the API gateway was timing out, and users were seeing 504 errors. When I asked how many requests per second the system was handling, the answer was &ldquo;I don&rsquo;t know.&rdquo; When I asked what the expected load was, the answer was &ldquo;I didn&rsquo;t think about that.&rdquo;</p>