← Back to the directory

donnemartin/system-design-primer

Loading README…

	Short	Medium	Long
Read through the System design topics to get a broad understanding of how systems work	👍	👍	👍
Read through a few articles in the Company engineering blogs for the companies you are interviewing with	👍	👍	👍
Read through a few Real world architectures	👍	👍	👍
Review How to approach a system design interview question	👍	👍	👍
Work through System design interview questions with solutions	Some	Many	Most
Work through Object-oriented design interview questions with solutions	Some	Many	Most
Review Additional system design interview questions	Some	Many	Most

Question
Design Pastebin.com (or Bit.ly)	Solution
Design the Twitter timeline and search (or Facebook feed and search)	Solution
Design a web crawler	Solution
Design Mint.com	Solution
Design the data structures for a social network	Solution
Design a key-value store for a search engine	Solution
Design Amazon's sales ranking by category feature	Solution
Design a system that scales to millions of users on AWS	Solution
Add a system design question	Contribute

Question
Design a hash map	Solution
Design a least recently used cache	Solution
Design a call center	Solution
Design a deck of cards	Solution
Design a parking lot	Solution
Design a chat server	Solution
Design a circular array	Contribute
Add an object-oriented design question	Contribute

Duration	Acceptable downtime
Downtime per year	8h 45min 57s
Downtime per month	43m 49.7s
Downtime per week	10m 4.8s
Downtime per day	1m 26.4s

Duration	Acceptable downtime
Downtime per year	52min 35.7s
Downtime per month	4m 23s
Downtime per week	1m 5s
Downtime per day	8.6s

Verb	Description	Idempotent*	Safe	Cacheable
GET	Reads a resource	Yes	Yes	Yes
POST	Creates a resource or trigger a process that handles data	No	No	Yes if response contains freshness info
PUT	Creates or replace a resource	Yes	No	No
PATCH	Partially updates a resource	No	No	Yes if response contains freshness info
DELETE	Deletes a resource	Yes	No	No

Operation	RPC	REST
Signup	POST /signup	POST /persons
Resign	POST /resign { "personid": "1234" }	DELETE /persons/1234
Read a person	GET /readPerson?personid=1234	GET /persons/1234
Read a person’s items list	GET /readUsersItemsList?personid=1234	GET /persons/1234/items
Add an item to a person’s items	POST /addItemToUsersItemsList { "personid": "1234"; "itemid": "456" }	POST /persons/1234/items { "itemid": "456" }
Update an item	POST /modifyItem { "itemid": "456"; "key": "value" }	PUT /items/456 { "key": "value" }
Delete an item	POST /removeItem { "itemid": "456" }	DELETE /items/456

Question	Reference(s)
Design a file sync service like Dropbox	youtube.com
Design a search engine like Google	queue.acm.org stackexchange.com ardendertat.com stanford.edu
Design a scalable web crawler like Google	quora.com
Design Google docs	code.google.com neil.fraser.name
Design a key-value store like Redis	codecapsule.com allthingsdistributed.com
Design a cache system like Memcached	slideshare.net
Design a recommendation system like Amazon's	hulu.com ijcai13.org
Design a tinyurl system like Bitly	n00tc0d3r.blogspot.com
Design a chat app like WhatsApp	highscalability.com
Design a picture sharing system like Instagram	highscalability.com highscalability.com
Design the Facebook news feed function	quora.com quora.com slideshare.net
Design the Facebook timeline function	facebook.com highscalability.com
Design the Facebook chat function	erlang-factory.com facebook.com
Design a graph search function like Facebook's	facebook.com facebook.com facebook.com
Design a content delivery network like CloudFlare	figshare.com
Design a trending topic system like Twitter's	michael-noll.com snikolov .wordpress.com
Design a random ID generation system	blog.twitter.com github.com
Return the top k requests during a time interval	cs.ucsb.edu wpi.edu
Design a system that serves data from multiple data centers	highscalability.com
Design an online multiplayer card game	indieflashblog.com buildnewgames.com
Design a garbage collection system	stuffwithstuff.com washington.edu
Design an API rate limiter	https://stripe.com/blog/
Design a Stock Exchange (like NASDAQ or Binance)	Jane Street Golang Implementation Go Implementation
Add a system design question	Contribute

Type	System	Reference(s)
Data processing	MapReduce - Distributed data processing from Google	research.google.com
Data processing	Spark - Distributed data processing from Databricks	slideshare.net
Data processing	Storm - Distributed data processing from Twitter	slideshare.net

Data store	Bigtable - Distributed column-oriented database from Google	harvard.edu
Data store	HBase - Open source implementation of Bigtable	slideshare.net
Data store	Cassandra - Distributed column-oriented database from Facebook	slideshare.net
Data store	DynamoDB - Document-oriented database from Amazon	harvard.edu
Data store	MongoDB - Document-oriented database	slideshare.net
Data store	Spanner - Globally-distributed database from Google	research.google.com
Data store	Memcached - Distributed memory caching system	slideshare.net
Data store	Redis - Distributed memory caching system with persistence and value types	slideshare.net

File system	Google File System (GFS) - Distributed file system	research.google.com
File system	Hadoop File System (HDFS) - Open source implementation of GFS	apache.org

Misc	Chubby - Lock service for loosely-coupled distributed systems from Google	research.google.com
Misc	Dapper - Distributed systems tracing infrastructure	research.google.com
Misc	Kafka - Pub/sub message queue from LinkedIn	slideshare.net
Misc	Zookeeper - Centralized infrastructure and services enabling synchronization	slideshare.net
	Add an architecture	Contribute

Company	Reference(s)
Amazon	Amazon architecture
Cinchcast	Producing 1,500 hours of audio every day
DataSift	Realtime datamining At 120,000 tweets per second
Dropbox	How we've scaled Dropbox
ESPN	Operating At 100,000 duh nuh nuhs per second
Google	Google architecture
Instagram	14 million users, terabytes of photos What powers Instagram
Justin.tv	Justin.Tv's live video broadcasting architecture
Facebook	Scaling memcached at Facebook TAO: Facebook’s distributed data store for the social graph Facebook’s photo storage How Facebook Live Streams To 800,000 Simultaneous Viewers
Flickr	Flickr architecture
Mailbox	From 0 to one million users in 6 weeks
Netflix	A 360 Degree View Of The Entire Netflix Stack Netflix: What Happens When You Press Play?
Pinterest	From 0 To 10s of billions of page views a month 18 million visitors, 10x growth, 12 employees
Playfish	50 million monthly users and growing
PlentyOfFish	PlentyOfFish architecture
Salesforce	How they handle 1.3 billion transactions a day
Stack Overflow	Stack Overflow architecture
TripAdvisor	40M visitors, 200M dynamic page views, 30TB data
Tumblr	15 billion page views a month
Twitter	Making Twitter 10000 percent faster Storing 250 million tweets a day using MySQL 150M active users, 300K QPS, a 22 MB/S firehose Timelines at scale Big and small data at Twitter Operations at Twitter: scaling beyond 100 million users How Twitter Handles 3,000 Images Per Second
Uber	How Uber scales their real-time market platform Lessons Learned From Scaling Uber To 2000 Engineers, 1000 Services, And 8000 Git Repositories
WhatsApp	The WhatsApp architecture Facebook bought for $19 billion
YouTube	YouTube scalability YouTube architecture

The System Design Primer

Motivation

Learn how to design large-scale systems

Learn from the open source community

Prep for the system design interview

Anki flashcards

Coding Resource: Interactive Coding Challenges

Contributing

Index of system design topics

Study guide

How to approach a system design interview question

Step 1: Outline use cases, constraints, and assumptions

Step 2: Create a high level design

Step 3: Design core components

Step 4: Scale the design

Back-of-the-envelope calculations

Source(s) and further reading

System design interview questions with solutions

Design Pastebin.com (or Bit.ly)

Design the Twitter timeline and search (or Facebook feed and search)

Design a web crawler

Design Mint.com

Design the data structures for a social network

Design a key-value store for a search engine

Design Amazon's sales ranking by category feature

Design a system that scales to millions of users on AWS

Object-oriented design interview questions with solutions

System design topics: start here

Step 1: Review the scalability video lecture

Step 2: Review the scalability article

Next steps

Performance vs scalability

Source(s) and further reading

Latency vs throughput

Source(s) and further reading

Availability vs consistency

CAP theorem

CP - consistency and partition tolerance

AP - availability and partition tolerance

Source(s) and further reading

Consistency patterns

Weak consistency

Eventual consistency

Strong consistency

Source(s) and further reading

Availability patterns

Fail-over

Active-passive

Active-active

Disadvantage(s): failover

Replication

Master-slave and master-master

Availability in numbers

99.9% availability - three 9s

99.99% availability - four 9s

Availability in parallel vs in sequence

In sequence

In parallel

Domain name system

Disadvantage(s): DNS

Source(s) and further reading

Content delivery network

Push CDNs

Pull CDNs

Disadvantage(s): CDN

Source(s) and further reading

Load balancer

Layer 4 load balancing

Layer 7 load balancing

Horizontal scaling

Disadvantage(s): horizontal scaling

Disadvantage(s): load balancer

Source(s) and further reading

Reverse proxy (web server)

Load balancer vs reverse proxy

Disadvantage(s): reverse proxy

Source(s) and further reading

Application layer

Microservices

Service Discovery