Thread by @oldmoe

A typical Ruby/Rails web app performance is usually limited by one of the following (depending on usage patterns):

1. Compute
2. Memory
3. IO (network & disk)

The good thing is, you can ease these without having to touch your application code.

Read on ⬇️

1. Compute

It's everywhere, even db ops can be compute intensive. Though Ruby itself is usually the culprit, specially if there is a lot of logic or template/json rendering

Quick fixes:

- Enable Yjit
- Oj gem for JSON
- A fibered server like Falcon (less context switching)

2. Memory

Ruby is known for being memory hungry, your app processes can consume a lot of memory specially when you use many processes/threads

Quick fixes:
- Use Jemalloc
- A preforked server like Falcon
- A fibered server like Falcon (less memory fragmentation)

3. IO

A lot of your app time is spent on IO, whether the network or any data store you are using.

Quick fixes:
- Use SQLite (via Litestack, eliminate network and lots of Ruby overhead)
- A fibered server like Falcon to increase concurrency

In summary:

- Falcon as your server
- Litestack for data
- Oj for JSON
- Jemalloc
- Yjit

The best part? All these are transparent (or mostly transparent) and they require no changes to your app besides some config params

Configure them once and get a faster & leaner app