optimizing-performance

1# Optimizing Performance
2 
3### When to Load
4 
5- **Trigger**: Diagnosing slowness, profiling, caching strategies, reducing load times, bundle size optimization
6- **Skip**: Correctness-focused work where performance is not a concern
7 
8## Performance Optimization Workflow
9 
10Copy this checklist and track progress:
11 
12```
13Performance Optimization Progress:
14- [ ] Step 1: Measure baseline performance
15- [ ] Step 2: Identify bottlenecks
16- [ ] Step 3: Apply targeted optimizations
17- [ ] Step 4: Measure again and compare
18- [ ] Step 5: Repeat if targets not met
19```
20 
21**Critical Rule**: Never optimize without data. Always profile before and after changes.
22 
23## Step 1: Measure Baseline
24 
25### Profiling Commands
26 
27```bash
28# Node.js profiling
29node --prof app.js
30node --prof-process isolate*.log > profile.txt
31 
32# Python profiling
33python -m cProfile -o profile.stats app.py
34python -m pstats profile.stats
35 
36# Web performance
37lighthouse https://example.com --output=json
38```
39 
40## Step 2: Identify Bottlenecks
41 
42### Common Bottleneck Categories
43 
44| Category | Symptoms                         | Tools                           |
45| -------- | -------------------------------- | ------------------------------- |
46| CPU      | High CPU usage, slow computation | Profiler, flame graphs          |
47| Memory   | High RAM, GC pauses, OOM         | Heap snapshots, memory profiler |
48| I/O      | Slow disk/network, waiting       | strace, network inspector       |
49…