Profiling to make your Rails app faster

on YouTube ↗41m

" summary

Uses rack-mini-profiler to find that checkouts slow because payment capture and email hit remote services and moving those to ActiveJob makes requests fast; caching product partials drops product index from ~600ms to ~40ms (~15x); boot time regresses by ~4s due to shipping rates initializer, moving it to a rake task and streaming the download halves memory allocations; fixes an N+1 on cart items with includes and verifies ~10x win with benchmark/ips.

AI-written summary · about

" chapters (13)

1. 0:00Start
2. 4:46Upgrade Ruby
3. 7:04Database profiling
4. 7:53Memory profiling
5. 10:12Call-stack profiling
6. 16:41Controller
7. 21:37Development vs Production vs Test
8. 29:56Code loading
9. 34:56Production profiling
10. 39:39Rack Mini Profiler
11. 39:56Use Caching
12. 40:13Memory profile complex methods
13. 40:34Benchmarking

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