// Optimized query StarCluster.find() .skip((pageNum - 1) * 1000) .limit(1000) .exec((err, data) => { ... }); After rebuilding the API, Alex reran the load test. This time, top showed mongod memory usage dropping by 80%:
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 12345 node 20 0 340000 120000 20000 5.0 1.5 12:34:56 node 12346 mongod 20 0 1500000 180000 15000 1.5 4.8 34:21:34 mongod The next morning, the team deployed the app. Users flocked to the stellar map, raving about its speed. The client sent a thank-you message: "That star.tar.gz dataset was a beast, huh?"
Chapter 1: The Mysterious Crash Alex, a junior developer at StarCode Studios, stared at their laptop screen, blinking at the terminal. It was 11 PM, and the team was racing to deploy a new MERN stack application that handled real-time astronomy data. The client had provided a compressed dataset called star.tar.gz , promising it would "revolutionize our API performance."
// Original query causing the crash StarCluster.find().exec((err, data) => { ... }); They optimized it with a limit and pagination, and added indexing to MongoDB’s position field:
Alex began by unzipping the file: