--- title: My API Is Up, but Slow. Is It My Code or the Server? description: A walkthrough shows how to diagnose a slow API on a small VPS by correlating application metrics (latency, request counts, errors, JVM CPU/memory) with... canonical: https://daily.dev/posts/hem5vcyul twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: My API Is Up, but Slow. Is It My Code or the Server? | daily.dev og:description: A walkthrough shows how to diagnose a slow API on a small VPS by correlating application metrics (latency, request counts, errors, JVM CPU/memory) with... og:url: https://daily.dev/posts/hem5vcyul og:image: https://api.daily.dev/og/posts/hEM5VCyUl.png og:image:alt: Post cover image og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # My API Is Up, but Slow. Is It My Code or the Server? **[Efficient Self-Hosting](https://daily.dev/sources/efficientselfhosting)** · [@ejboy](https://daily.dev/ejboy) · 0 upvotes · 0 comments ## Summary A walkthrough shows how to diagnose a slow API on a small VPS by correlating application metrics (latency, request counts, errors, JVM CPU/memory) with host-level metrics (CPU, RAM, disk) on a shared timeline. Using StatLite, which reads Spring Boot Actuator metrics and keeps history in a local SQLite file, the scenario traces a latency spike to a CPU-heavy maintenance job competing for CPU time on a single-core server rather than an application regression. A table summarizes common patterns (traffic up, app CPU up, host CPU up, memory climbing) and where to investigate next for each. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Similar posts on daily.dev - [Why Is Your Linux Server Slow? 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