Upgrade to Pro
— share decks privately, control downloads, hide ads and more …
Speaker Deck
Features
Speaker Deck
PRO
Sign in
Sign up for free
Search
Search
Cheating Your Way to Webscale
Search
Matt Robenolt
May 02, 2014
Programming
13
1.4k
Cheating Your Way to Webscale
Python Nordeste, May 2nd 2014
Matt Robenolt
May 02, 2014
Tweet
Share
More Decks by Matt Robenolt
See All by Matt Robenolt
Everything is broken and I don't know why.
mattrobenolt
0
44
I am bad at my job.
mattrobenolt
0
200
Everything is broken, and I don't know why. Python edition.
mattrobenolt
1
200
Everything is broken, and I don't know why. Python edition.
mattrobenolt
2
580
Varnish: How We Do It
mattrobenolt
1
220
Everything is broken, and I don't know why.
mattrobenolt
7
1.5k
HTTP for Great Good
mattrobenolt
85
200k
Caching is Hard: Varnish @ Disqus
mattrobenolt
52
2.1M
Developing & Deploying "Large" Scale Web Applications
mattrobenolt
25
1.3k
Other Decks in Programming
See All in Programming
CSC305 Lecture 04
javiergs
PRO
0
230
dynamic!
moro
9
6.1k
育てるアーキテクチャ:戦い抜くPythonマイクロサービスの設計と進化戦略
fujidomoe
1
150
詳しくない分野でのVibe Codingで困ったことと学び/vibe-coding-in-unfamiliar-area
shibayu36
3
4k
Pythonスレッドとは結局何なのか? CPython実装から見るNoGIL時代の変化
curekoshimizu
4
1.2k
Serena MCPのすすめ
wadakatu
4
880
2025年版 サーバーレス Web アプリケーションの作り方
hayatow
23
25k
Чего вы не знали о строках в Python – Василий Рябов, PythoNN
sobolevn
0
150
Django Ninja による API 開発効率化とリプレースの実践
kashewnuts
0
900
明日から始めるリファクタリング
ryounasso
0
110
AIで開発生産性を上げる個人とチームの取り組み
taniigo
0
130
Back to the Future: Let me tell you about the ACP protocol
terhechte
0
130
Featured
See All Featured
Principles of Awesome APIs and How to Build Them.
keavy
127
17k
JavaScript: Past, Present, and Future - NDC Porto 2020
reverentgeek
52
5.6k
KATA
mclloyd
32
15k
The Straight Up "How To Draw Better" Workshop
denniskardys
237
140k
Scaling GitHub
holman
463
140k
The Psychology of Web Performance [Beyond Tellerrand 2023]
tammyeverts
49
3.1k
Refactoring Trust on Your Teams (GOTO; Chicago 2020)
rmw
35
3.2k
The Art of Programming - Codeland 2020
erikaheidi
56
14k
Building Applications with DynamoDB
mza
96
6.6k
Navigating Team Friction
lara
189
15k
Design and Strategy: How to Deal with People Who Don’t "Get" Design
morganepeng
132
19k
How to train your dragon (web standard)
notwaldorf
96
6.3k
Transcript
Python Nordeste May 2nd 2014 Matt Robenolt Cheating Your Way
to #webscale
Hello < me irl
Lead Operations Engineer
Core Contributor
So what is #webscale?
10 million requests per second 4ms mean response time asynchronous
io mongodb
10 million requests per second 4ms mean response time asynchronous
io mongodb NOPE
Disqus only does 150 req/s per web server. * we
also write some bad code
150 12,960,000 388,800,000 per second per day per month real
world #webscale
Scale is about hiding the fact that your application is
actually really slow.
If your application feels fast, then it’s probably good enough.
Users hate waiting for shit.
So how do we do it?
Cheating 101
When a user asks for new data, let’s give them
old data instead.
When a user asks for new data, let’s give them
old data instead. Caching
When telling us to do something, let’s say we did
and maybe do it later.
When telling us to do something, let’s say we did
and maybe do it later. Queueing
Rule #1 Don’t get caught.
Rule #2 Don’t get caught.
Rule #3 Don’t get caught.
HTTP Caching
Introducing
tl;dr Varnish sits between your application and your users Internet
Let’s talk about HTTP. Hypertext Transport Protocol
$ curl -v disqus.com
> GET / HTTP/1.1 > User-Agent: curl/7.24.0 > Host: disqus.com
> Accept: */* > < HTTP/1.1 200 OK < Server: nginx < Date: Fri, 02 May 2014 06:38:37 GMT < Content-Type: text/html; charset=utf-8 < Content-Length: 10453 < Last-Modified: Fri, 30 Aug 2013 00:32:14 GMT < Vary: Accept-Encoding < Expires: Fri, 02 May 2014 06:43:36 GMT < Cache-Control: public, max-age=300
> GET / HTTP/1.1 > User-Agent: curl/7.24.0 > Host: disqus.com
> Accept: */* > < HTTP/1.1 200 OK < Server: nginx < Date: Fri, 02 May 2014 06:38:37 GMT < Content-Type: text/html; charset=utf-8 < Content-Length: 10453 < Last-Modified: Fri, 30 Aug 2013 00:32:14 GMT < Vary: Accept-Encoding < Expires: Fri, 02 May 2014 06:43:36 GMT < Cache-Control: public, max-age=300 Request
> GET / HTTP/1.1 > User-Agent: curl/7.24.0 > Host: disqus.com
> Accept: */* > < HTTP/1.1 200 OK < Server: nginx < Date: Fri, 02 May 2014 06:38:37 GMT < Content-Type: text/html; charset=utf-8 < Content-Length: 10453 < Last-Modified: Fri, 30 Aug 2013 00:32:14 GMT < Vary: Accept-Encoding < Expires: Fri, 02 May 2014 06:43:36 GMT < Cache-Control: public, max-age=300 Method
> GET / HTTP/1.1 > User-Agent: curl/7.24.0 > Host: disqus.com
> Accept: */* > < HTTP/1.1 200 OK < Server: nginx < Date: Fri, 02 May 2014 06:38:37 GMT < Content-Type: text/html; charset=utf-8 < Content-Length: 10453 < Last-Modified: Fri, 30 Aug 2013 00:32:14 GMT < Vary: Accept-Encoding < Expires: Fri, 02 May 2014 06:43:36 GMT < Cache-Control: public, max-age=300 Path
> GET / HTTP/1.1 > User-Agent: curl/7.24.0 > Host: disqus.com
> Accept: */* > < HTTP/1.1 200 OK < Server: nginx < Date: Fri, 02 May 2014 06:38:37 GMT < Content-Type: text/html; charset=utf-8 < Content-Length: 10453 < Last-Modified: Fri, 30 Aug 2013 00:32:14 GMT < Vary: Accept-Encoding < Expires: Fri, 02 May 2014 06:43:36 GMT < Cache-Control: public, max-age=300 Version
> GET / HTTP/1.1 > User-Agent: curl/7.24.0 > Host: disqus.com
> Accept: */* > < HTTP/1.1 200 OK < Server: nginx < Date: Fri, 02 May 2014 06:38:37 GMT < Content-Type: text/html; charset=utf-8 < Content-Length: 10453 < Last-Modified: Fri, 30 Aug 2013 00:32:14 GMT < Vary: Accept-Encoding < Expires: Fri, 02 May 2014 06:43:36 GMT < Cache-Control: public, max-age=300 Headers
> GET / HTTP/1.1 > User-Agent: curl/7.24.0 > Host: disqus.com
> Accept: */* > < HTTP/1.1 200 OK < Server: nginx < Date: Fri, 02 May 2014 06:38:37 GMT < Content-Type: text/html; charset=utf-8 < Content-Length: 10453 < Last-Modified: Fri, 30 Aug 2013 00:32:14 GMT < Vary: Accept-Encoding < Expires: Fri, 02 May 2014 06:43:36 GMT < Cache-Control: public, max-age=300 Response
> GET / HTTP/1.1 > User-Agent: curl/7.24.0 > Host: disqus.com
> Accept: */* > < HTTP/1.1 200 OK < Server: nginx < Date: Fri, 02 May 2014 06:38:37 GMT < Content-Type: text/html; charset=utf-8 < Content-Length: 10453 < Last-Modified: Fri, 30 Aug 2013 00:32:14 GMT < Vary: Accept-Encoding < Expires: Fri, 02 May 2014 06:43:36 GMT < Cache-Control: public, max-age=300 Status
> GET / HTTP/1.1 > User-Agent: curl/7.24.0 > Host: disqus.com
> Accept: */* > < HTTP/1.1 200 OK < Server: nginx < Date: Fri, 02 May 2014 06:38:37 GMT < Content-Type: text/html; charset=utf-8 < Content-Length: 10453 < Last-Modified: Fri, 30 Aug 2013 00:32:14 GMT < Vary: Accept-Encoding < Expires: Fri, 02 May 2014 06:43:36 GMT < Cache-Control: public, max-age=300 Headers
> GET / HTTP/1.1 > User-Agent: curl/7.24.0 > Host: disqus.com
> Accept: */* > < HTTP/1.1 200 OK < Server: nginx < Date: Fri, 02 May 2014 06:38:37 GMT < Content-Type: text/html; charset=utf-8 < Content-Length: 10453 < Last-Modified: Fri, 30 Aug 2013 00:32:14 GMT < Vary: Accept-Encoding < Expires: Fri, 02 May 2014 06:43:36 GMT < Cache-Control: public, max-age=300
> GET / HTTP/1.1 > User-Agent: curl/7.24.0 > Host: disqus.com
> Accept: */* > < HTTP/1.1 200 OK < Server: nginx < Date: Fri, 02 May 2014 06:38:37 GMT < Content-Type: text/html; charset=utf-8 < Content-Length: 10453 < Last-Modified: Fri, 30 Aug 2013 00:32:14 GMT < Vary: Accept-Encoding < Expires: Fri, 02 May 2014 06:43:36 GMT < Cache-Control: public, max-age=300 For 300 seconds, all users will get the same response without talking to our application.
> GET / HTTP/1.1 > User-Agent: curl/7.24.0 > Host: disqus.com
> Accept: */* > < HTTP/1.1 200 OK < Server: nginx < Date: Fri, 02 May 2014 06:38:37 GMT < Content-Type: text/html; charset=utf-8 < Content-Length: 10453 < Last-Modified: Fri, 30 Aug 2013 00:32:14 GMT < Vary: Accept-Encoding < Expires: Fri, 02 May 2014 06:43:36 GMT < Cache-Control: public, max-age=300 With power comes great responsibility.
GET / INTERNET Varnish Web servers
GET / INTERNET Varnish Web servers CACHED! “Cache-Control: max-age=300”
GET / INTERNET Varnish Web servers
GET / INTERNET Varnish Web servers CACHED!
BUT WAIT… THERE’S MORE
COLLAPSING REQUEST
GET / INTERNET Varnish Web servers
INTERNET Varnish Web servers GET /
INTERNET Varnish Web servers GET / If multiple users request
the same object, Varnish makes one fetch and returns to all users.
Queueing
Do as little work as possible, and return a promise
that this work will be done.
INTERNET Web servers Task workers Slow/Fast Data store Queue POST
/foo
INTERNET Web servers Task workers Slow/Fast Data store Queue POST
/foo
INTERNET Web servers Task workers Slow/Fast Data store Queue POST
/foo Workers can rate limit, debounce, increment counters, generate a fast materialized view, etc.
INTERNET Web servers Task workers Slow/Fast Data store Queue POST
/foo Make sure your tasks finish before a user tries to read the data back.
Final Thoughts
Understand your application. Where can you cheat without disrupting user
experience? Is seeing a few seconds old data going to damage a product?
Cheating should only enhance user experience.
Cheat any way you can, just don’t get caught.
Django & Varnish & RabbitMQ & Celery & PostgreSQL &
Redis & Cassandra & Riak Thanks
Questions? I have answers. ^ github.com/mattrobenolt @mattrobenolt some