Developer time is important.

Performance Tooling

Jack Lawson

Software Engineer, Airbnb

@ajacksified

The Web Request

1. User enters url in browser
2. DNS fetch
3. Hit CDN server from DNS
4. Request from origin app server
5. App server requests data from database / services
6. Browser starts receiving html
7. Load styles, images, js from CDN
8. Finished loading assets
9. Finished running post-load scripts

Backend performance

1. User enters url in browser
2. DNS fetch
3. Hit CDN server from DNS
4. Request from origin app server
5. App server requests data from database / services
6. Browser starts receiving html
7. Load styles, images, js from CDN
8. Finished loading assets
9. Finished running post-load scripts

Frontend performance

1. User enters url in browser
2. DNS fetch
3. Hit CDN server from DNS
4. Request from origin app server
5. App server requests data from database / services
6. Browser starts receiving html
7. Load styles, images, js from CDN
8. Finished loading assets
9. Finished running post-load scripts

Page Load Milestones

1. User enters url in browser
2. DNS fetch
3. Hit CDN server from DNS
4. Request from origin app server
5. App server requests data from database / services
6. (TTFB) Browser starts receiving html
7. (Render) Load styles, images, js from CDN
8. (Load Time) Finished loading assets
9. (Finished) Finished running post-load scripts

1. User enters url in browser
2. DNS fetch
3. Hit CDN server from DNS
4. Request from origin app server
5. App server requests data from database / services
6. (TTFB) Browser starts receiving html

NewRelic Performance Monitoring

NewRelic helps you identify slow pages and figure out why they're slow.

Caching

Skip hitting your server entirely.

• 7. (Render) Load styles, images, js from CDN
• 8. (Load Time) Finished loading assets
• 9. (Finished) Finished running post-load scripts

Performance Golden Rule

Make Less Requests for Smaller Content

In the Cloud

The Speed of Light

299,792,458 m / s

From EC2 in Virginia

• 15ms to San Francisco
• 36ms to Tokyo

I Don't Have a Direct Cable From My Server In Virginia to My Computer

distance * speed of light gives us two things to change

Lower the distance

Increase the speed of light

Wormholes

Are Prohibitively Expensive

Move The Content Closer

Edge Caching via Akamai

Measuring Your Frontend Performance

RUM (Real User Metrics)

New Relic's Apdex

Your Browser's Network Tab

PageSpeed

WebPageTest

Tying It All Together

• Performance increases happiness and decreases bounce rate
• Focus on efficient fixes by measuring impact
• Identify slow requests with NewRelic and RUM
• Identify what's slow with WebPageTest, browser tests, and PageSpeed
• Track fixes with NewRelic and RUM

Any questions?