diff --git a/README.md b/README.md
index 266f8b16..588fc8d1 100644
--- a/README.md
+++ b/README.md
@@ -4,181 +4,13 @@
# The System Design Primer
-
- 
-
-
-
+# Intro
## Motivation
> Learn how to design large-scale systems.
>
> Prep for the system design interview.
-### Learn how to design large-scale systems
-
-Learning how to design scalable systems will help you become a better engineer.
-
-System design is a broad topic. There is a **vast amount of resources scattered throughout the web** on system design principles.
-
-This repo is an **organized collection** of resources to help you learn how to build systems at scale.
-
-### Learn from the open source community
-
-This is a continually updated, open source project.
-
-[Contributions](#contributing) are welcome!
-
-### Prep for the system design interview
-
-In addition to coding interviews, system design is a **required component** of the **technical interview process** at many tech companies.
-
-**Practice common system design interview questions** and **compare** your results with **sample solutions**: discussions, code, and diagrams.
-
-Additional topics for interview prep:
-
-* [Study guide](#study-guide)
-* [How to approach a system design interview question](#how-to-approach-a-system-design-interview-question)
-* [System design interview questions, **with solutions**](#system-design-interview-questions-with-solutions)
-* [Object-oriented design interview questions, **with solutions**](#object-oriented-design-interview-questions-with-solutions)
-* [Additional system design interview questions](#additional-system-design-interview-questions)
-
-## Anki flashcards
-
-
- 
-
-
-
-The provided [Anki flashcard decks](https://apps.ankiweb.net/) use spaced repetition to help you retain key system design concepts.
-
-* [System design deck](https://github.com/donnemartin/system-design-primer/tree/master/resources/flash_cards/System%20Design.apkg)
-* [System design exercises deck](https://github.com/donnemartin/system-design-primer/tree/master/resources/flash_cards/System%20Design%20Exercises.apkg)
-* [Object oriented design exercises deck](https://github.com/donnemartin/system-design-primer/tree/master/resources/flash_cards/OO%20Design.apkg)
-
-Great for use while on-the-go.
-
-### Coding Resource: Interactive Coding Challenges
-
-Looking for resources to help you prep for the [**Coding Interview**](https://github.com/donnemartin/interactive-coding-challenges)?
-
-
- 
-
-
-
-Check out the sister repo [**Interactive Coding Challenges**](https://github.com/donnemartin/interactive-coding-challenges), which contains an additional Anki deck:
-
-* [Coding deck](https://github.com/donnemartin/interactive-coding-challenges/tree/master/anki_cards/Coding.apkg)
-
-## Contributing
-
-> Learn from the community.
-
-Feel free to submit pull requests to help:
-
-* Fix errors
-* Improve sections
-* Add new sections
-* [Translate](https://github.com/donnemartin/system-design-primer/issues/28)
-
-Content that needs some polishing is placed [under development](#under-development).
-
-Review the [Contributing Guidelines](CONTRIBUTING.md).
-
-## Index of system design topics
-
-> Summaries of various system design topics, including pros and cons. **Everything is a trade-off**.
->
-> Each section contains links to more in-depth resources.
-
-
- 
-
-
-
-* [System design topics: start here](#system-design-topics-start-here)
- * [Step 1: Review the scalability video lecture](#step-1-review-the-scalability-video-lecture)
- * [Step 2: Review the scalability article](#step-2-review-the-scalability-article)
- * [Next steps](#next-steps)
-* [Performance vs scalability](#performance-vs-scalability)
-* [Latency vs throughput](#latency-vs-throughput)
-* [Availability vs consistency](#availability-vs-consistency)
- * [CAP theorem](#cap-theorem)
- * [CP - consistency and partition tolerance](#cp---consistency-and-partition-tolerance)
- * [AP - availability and partition tolerance](#ap---availability-and-partition-tolerance)
-* [Consistency patterns](#consistency-patterns)
- * [Weak consistency](#weak-consistency)
- * [Eventual consistency](#eventual-consistency)
- * [Strong consistency](#strong-consistency)
-* [Availability patterns](#availability-patterns)
- * [Fail-over](#fail-over)
- * [Replication](#replication)
- * [Availability in numbers](#availability-in-numbers)
-* [Domain name system](#domain-name-system)
-* [Content delivery network](#content-delivery-network)
- * [Push CDNs](#push-cdns)
- * [Pull CDNs](#pull-cdns)
-* [Load balancer](#load-balancer)
- * [Active-passive](#active-passive)
- * [Active-active](#active-active)
- * [Layer 4 load balancing](#layer-4-load-balancing)
- * [Layer 7 load balancing](#layer-7-load-balancing)
- * [Horizontal scaling](#horizontal-scaling)
-* [Reverse proxy (web server)](#reverse-proxy-web-server)
- * [Load balancer vs reverse proxy](#load-balancer-vs-reverse-proxy)
-* [Application layer](#application-layer)
- * [Microservices](#microservices)
- * [Service discovery](#service-discovery)
-* [Database](#database)
- * [Relational database management system (RDBMS)](#relational-database-management-system-rdbms)
- * [Master-slave replication](#master-slave-replication)
- * [Master-master replication](#master-master-replication)
- * [Federation](#federation)
- * [Sharding](#sharding)
- * [Denormalization](#denormalization)
- * [SQL tuning](#sql-tuning)
- * [NoSQL](#nosql)
- * [Key-value store](#key-value-store)
- * [Document store](#document-store)
- * [Wide column store](#wide-column-store)
- * [Graph Database](#graph-database)
- * [SQL or NoSQL](#sql-or-nosql)
-* [Cache](#cache)
- * [Client caching](#client-caching)
- * [CDN caching](#cdn-caching)
- * [Web server caching](#web-server-caching)
- * [Database caching](#database-caching)
- * [Application caching](#application-caching)
- * [Caching at the database query level](#caching-at-the-database-query-level)
- * [Caching at the object level](#caching-at-the-object-level)
- * [When to update the cache](#when-to-update-the-cache)
- * [Cache-aside](#cache-aside)
- * [Write-through](#write-through)
- * [Write-behind (write-back)](#write-behind-write-back)
- * [Refresh-ahead](#refresh-ahead)
-* [Asynchronism](#asynchronism)
- * [Message queues](#message-queues)
- * [Task queues](#task-queues)
- * [Back pressure](#back-pressure)
-* [Communication](#communication)
- * [Transmission control protocol (TCP)](#transmission-control-protocol-tcp)
- * [User datagram protocol (UDP)](#user-datagram-protocol-udp)
- * [Remote procedure call (RPC)](#remote-procedure-call-rpc)
- * [Representational state transfer (REST)](#representational-state-transfer-rest)
-* [Security](#security)
-* [Appendix](#appendix)
- * [Powers of two table](#powers-of-two-table)
- * [Latency numbers every programmer should know](#latency-numbers-every-programmer-should-know)
- * [Additional system design interview questions](#additional-system-design-interview-questions)
- * [Real world architectures](#real-world-architectures)
- * [Company architectures](#company-architectures)
- * [Company engineering blogs](#company-engineering-blogs)
-* [Under development](#under-development)
-* [Credits](#credits)
-* [Contact info](#contact-info)
-* [License](#license)
-
## Study guide
> Suggested topics to review based on your interview timeline (short, medium, long).
@@ -215,6 +47,35 @@ Start broad and go deeper in a few areas. It helps to know a little about vario
| Work through [Object-oriented design interview questions with solutions](#object-oriented-design-interview-questions-with-solutions) | Some | Many | Most |
| Review [Additional system design interview questions](#additional-system-design-interview-questions) | Some | Many | Most |
+### Learn how to design large-scale systems
+
+Learning how to design scalable systems will help you become a better engineer.
+
+System design is a broad topic. There is a **vast amount of resources scattered throughout the web** on system design principles.
+
+This repo is an **organized collection** of resources to help you learn how to build systems at scale.
+
+### Learn from the open source community
+
+This is a continually updated, open source project.
+
+[Contributions](#contributing) are welcome!
+
+# Approaching the interview
+### Prep for the system design interview
+
+In addition to coding interviews, system design is a **required component** of the **technical interview process** at many tech companies.
+
+**Practice common system design interview questions** and **compare** your results with **sample solutions**: discussions, code, and diagrams.
+
+Additional topics for interview prep:
+
+* [Study guide](#study-guide)
+* [How to approach a system design interview question](#how-to-approach-a-system-design-interview-question)
+* [System design interview questions, **with solutions**](#system-design-interview-questions-with-solutions)
+* [Object-oriented design interview questions, **with solutions**](#object-oriented-design-interview-questions-with-solutions)
+* [Additional system design interview questions](#additional-system-design-interview-questions)
+
## How to approach a system design interview question
> How to tackle a system design interview question.
@@ -284,90 +145,37 @@ Check out the following links to get a better idea of what to expect:
* [Intro to Architecture and Systems Design Interviews](https://www.youtube.com/watch?v=ZgdS0EUmn70)
* [System design template](https://leetcode.com/discuss/career/229177/My-System-Design-Template)
-## System design interview questions with solutions
+# Systems Design
+## Index of system design topics
-> Common system design interview questions with sample discussions, code, and diagrams.
+> Summaries of various system design topics, including pros and cons. **Everything is a trade-off**.
>
-> Solutions linked to content in the `solutions/` folder.
+> Each section contains links to more in-depth resources.
-| Question | |
-|---|---|
-| Design Pastebin.com (or Bit.ly) | [Solution](solutions/system_design/pastebin/README.md) |
-| Design the Twitter timeline and search (or Facebook feed and search) | [Solution](solutions/system_design/twitter/README.md) |
-| Design a web crawler | [Solution](solutions/system_design/web_crawler/README.md) |
-| Design Mint.com | [Solution](solutions/system_design/mint/README.md) |
-| Design the data structures for a social network | [Solution](solutions/system_design/social_graph/README.md) |
-| Design a key-value store for a search engine | [Solution](solutions/system_design/query_cache/README.md) |
-| Design Amazon's sales ranking by category feature | [Solution](solutions/system_design/sales_rank/README.md) |
-| Design a system that scales to millions of users on AWS | [Solution](solutions/system_design/scaling_aws/README.md) |
-| Add a system design question | [Contribute](#contributing) |
+
+
+
+
-### Design Pastebin.com (or Bit.ly)
-
-[View exercise and solution](solutions/system_design/pastebin/README.md)
-
-
-
-### Design the Twitter timeline and search (or Facebook feed and search)
-
-[View exercise and solution](solutions/system_design/twitter/README.md)
-
-
-
-### Design a web crawler
-
-[View exercise and solution](solutions/system_design/web_crawler/README.md)
-
-
-
-### Design Mint.com
-
-[View exercise and solution](solutions/system_design/mint/README.md)
-
-
-
-### Design the data structures for a social network
-
-[View exercise and solution](solutions/system_design/social_graph/README.md)
-
-
-
-### Design a key-value store for a search engine
-
-[View exercise and solution](solutions/system_design/query_cache/README.md)
-
-
-
-### Design Amazon's sales ranking by category feature
-
-[View exercise and solution](solutions/system_design/sales_rank/README.md)
-
-
-
-### Design a system that scales to millions of users on AWS
-
-[View exercise and solution](solutions/system_design/scaling_aws/README.md)
-
-
-
-## Object-oriented design interview questions with solutions
-
-> Common object-oriented design interview questions with sample discussions, code, and diagrams.
->
-> Solutions linked to content in the `solutions/` folder.
-
->**Note: This section is under development**
-
-| Question | |
-|---|---|
-| Design a hash map | [Solution](solutions/object_oriented_design/hash_table/hash_map.ipynb) |
-| Design a least recently used cache | [Solution](solutions/object_oriented_design/lru_cache/lru_cache.ipynb) |
-| Design a call center | [Solution](solutions/object_oriented_design/call_center/call_center.ipynb) |
-| Design a deck of cards | [Solution](solutions/object_oriented_design/deck_of_cards/deck_of_cards.ipynb) |
-| Design a parking lot | [Solution](solutions/object_oriented_design/parking_lot/parking_lot.ipynb) |
-| Design a chat server | [Solution](solutions/object_oriented_design/online_chat/online_chat.ipynb) |
-| Design a circular array | [Contribute](#contributing) |
-| Add an object-oriented design question | [Contribute](#contributing) |
+# Concepts
+* [System design topics: start here](#system-design-topics-start-here)
+ * [Step 1: Review the scalability video lecture](#step-1-review-the-scalability-video-lecture)
+ * [Step 2: Review the scalability article](#step-2-review-the-scalability-article)
+ * [Next steps](#next-steps)
+* [Performance vs scalability](#performance-vs-scalability)
+* [Latency vs throughput](#latency-vs-throughput)
+* [Availability vs consistency](#availability-vs-consistency)
+ * [CAP theorem](#cap-theorem)
+ * [CP - consistency and partition tolerance](#cp---consistency-and-partition-tolerance)
+ * [AP - availability and partition tolerance](#ap---availability-and-partition-tolerance)
+* [Consistency patterns](#consistency-patterns)
+ * [Weak consistency](#weak-consistency)
+ * [Eventual consistency](#eventual-consistency)
+ * [Strong consistency](#strong-consistency)
+* [Availability patterns](#availability-patterns)
+ * [Fail-over](#fail-over)
+ * [Replication](#replication)
+ * [Availability in numbers](#availability-in-numbers)
## System design topics: start here
@@ -578,6 +386,67 @@ Availability (Total) = 1 - (1 - Availability (Foo)) * (1 - Availability (Bar))
If both `Foo` and `Bar` each had 99.9% availability, their total availability in parallel would be 99.9999%.
+# Components
+
+
+
+
+
+
+
+* [Domain name system](#domain-name-system)
+* [Content delivery network](#content-delivery-network)
+ * [Push CDNs](#push-cdns)
+ * [Pull CDNs](#pull-cdns)
+* [Load balancer](#load-balancer)
+ * [Active-passive](#active-passive)
+ * [Active-active](#active-active)
+ * [Layer 4 load balancing](#layer-4-load-balancing)
+ * [Layer 7 load balancing](#layer-7-load-balancing)
+ * [Horizontal scaling](#horizontal-scaling)
+* [Reverse proxy (web server)](#reverse-proxy-web-server)
+ * [Load balancer vs reverse proxy](#load-balancer-vs-reverse-proxy)
+* [Application layer](#application-layer)
+ * [Microservices](#microservices)
+ * [Service discovery](#service-discovery)
+* [Database](#database)
+ * [Relational database management system (RDBMS)](#relational-database-management-system-rdbms)
+ * [Master-slave replication](#master-slave-replication)
+ * [Master-master replication](#master-master-replication)
+ * [Federation](#federation)
+ * [Sharding](#sharding)
+ * [Denormalization](#denormalization)
+ * [SQL tuning](#sql-tuning)
+ * [NoSQL](#nosql)
+ * [Key-value store](#key-value-store)
+ * [Document store](#document-store)
+ * [Wide column store](#wide-column-store)
+ * [Graph Database](#graph-database)
+ * [SQL or NoSQL](#sql-or-nosql)
+* [Cache](#cache)
+ * [Client caching](#client-caching)
+ * [CDN caching](#cdn-caching)
+ * [Web server caching](#web-server-caching)
+ * [Database caching](#database-caching)
+ * [Application caching](#application-caching)
+ * [Caching at the database query level](#caching-at-the-database-query-level)
+ * [Caching at the object level](#caching-at-the-object-level)
+ * [When to update the cache](#when-to-update-the-cache)
+ * [Cache-aside](#cache-aside)
+ * [Write-through](#write-through)
+ * [Write-behind (write-back)](#write-behind-write-back)
+ * [Refresh-ahead](#refresh-ahead)
+* [Asynchronism](#asynchronism)
+ * [Message queues](#message-queues)
+ * [Task queues](#task-queues)
+ * [Back pressure](#back-pressure)
+* [Communication](#communication)
+ * [Transmission control protocol (TCP)](#transmission-control-protocol-tcp)
+ * [User datagram protocol (UDP)](#user-datagram-protocol-udp)
+ * [Remote procedure call (RPC)](#remote-procedure-call-rpc)
+ * [Representational state transfer (REST)](#representational-state-transfer-rest)
+* [Security](#security)
+
## Domain name system
@@ -1574,6 +1443,251 @@ Security is a broad topic. Unless you have considerable experience, a security
* [Security guide for developers](https://github.com/FallibleInc/security-guide-for-developers)
* [OWASP top ten](https://www.owasp.org/index.php/OWASP_Top_Ten_Cheat_Sheet)
+# Examples
+## System design interview questions with solutions
+
+> Common system design interview questions with sample discussions, code, and diagrams.
+>
+> Solutions linked to content in the `solutions/` folder.
+
+| Question | |
+|---|---|
+| Design Pastebin.com (or Bit.ly) | [Solution](solutions/system_design/pastebin/README.md) |
+| Design the Twitter timeline and search (or Facebook feed and search) | [Solution](solutions/system_design/twitter/README.md) |
+| Design a web crawler | [Solution](solutions/system_design/web_crawler/README.md) |
+| Design Mint.com | [Solution](solutions/system_design/mint/README.md) |
+| Design the data structures for a social network | [Solution](solutions/system_design/social_graph/README.md) |
+| Design a key-value store for a search engine | [Solution](solutions/system_design/query_cache/README.md) |
+| Design Amazon's sales ranking by category feature | [Solution](solutions/system_design/sales_rank/README.md) |
+| Design a system that scales to millions of users on AWS | [Solution](solutions/system_design/scaling_aws/README.md) |
+| Add a system design question | [Contribute](#contributing) |
+
+### Design Pastebin.com (or Bit.ly)
+
+[View exercise and solution](solutions/system_design/pastebin/README.md)
+
+
+
+### Design the Twitter timeline and search (or Facebook feed and search)
+
+[View exercise and solution](solutions/system_design/twitter/README.md)
+
+
+
+### Design a web crawler
+
+[View exercise and solution](solutions/system_design/web_crawler/README.md)
+
+
+
+### Design Mint.com
+
+[View exercise and solution](solutions/system_design/mint/README.md)
+
+
+
+### Design the data structures for a social network
+
+[View exercise and solution](solutions/system_design/social_graph/README.md)
+
+
+
+### Design a key-value store for a search engine
+
+[View exercise and solution](solutions/system_design/query_cache/README.md)
+
+
+
+### Design Amazon's sales ranking by category feature
+
+[View exercise and solution](solutions/system_design/sales_rank/README.md)
+
+
+
+### Design a system that scales to millions of users on AWS
+
+[View exercise and solution](solutions/system_design/scaling_aws/README.md)
+
+
+
+## Object-oriented design interview questions with solutions
+
+> Common object-oriented design interview questions with sample discussions, code, and diagrams.
+>
+> Solutions linked to content in the `solutions/` folder.
+
+>**Note: This section is under development**
+
+| Question | |
+|---|---|
+| Design a hash map | [Solution](solutions/object_oriented_design/hash_table/hash_map.ipynb) |
+| Design a least recently used cache | [Solution](solutions/object_oriented_design/lru_cache/lru_cache.ipynb) |
+| Design a call center | [Solution](solutions/object_oriented_design/call_center/call_center.ipynb) |
+| Design a deck of cards | [Solution](solutions/object_oriented_design/deck_of_cards/deck_of_cards.ipynb) |
+| Design a parking lot | [Solution](solutions/object_oriented_design/parking_lot/parking_lot.ipynb) |
+| Design a chat server | [Solution](solutions/object_oriented_design/online_chat/online_chat.ipynb) |
+| Design a circular array | [Contribute](#contributing) |
+| Add an object-oriented design question | [Contribute](#contributing) |
+
+
+### Real world architectures
+
+> Articles on how real world systems are designed.
+
+
+ 
+
+ Source: Twitter timelines at scale
+
+
+**Don't focus on nitty gritty details for the following articles, instead:**
+
+* Identify shared principles, common technologies, and patterns within these articles
+* Study what problems are solved by each component, where it works, where it doesn't
+* Review the lessons learned
+
+|Type | System | Reference(s) |
+|---|---|---|
+| Data processing | **MapReduce** - Distributed data processing from Google | [research.google.com](http://static.googleusercontent.com/media/research.google.com/zh-CN/us/archive/mapreduce-osdi04.pdf) |
+| Data processing | **Spark** - Distributed data processing from Databricks | [slideshare.net](http://www.slideshare.net/AGrishchenko/apache-spark-architecture) |
+| Data processing | **Storm** - Distributed data processing from Twitter | [slideshare.net](http://www.slideshare.net/previa/storm-16094009) |
+| | | |
+| Data store | **Bigtable** - Distributed column-oriented database from Google | [harvard.edu](http://www.read.seas.harvard.edu/~kohler/class/cs239-w08/chang06bigtable.pdf) |
+| Data store | **HBase** - Open source implementation of Bigtable | [slideshare.net](http://www.slideshare.net/alexbaranau/intro-to-hbase) |
+| Data store | **Cassandra** - Distributed column-oriented database from Facebook | [slideshare.net](http://www.slideshare.net/planetcassandra/cassandra-introduction-features-30103666)
+| Data store | **DynamoDB** - Document-oriented database from Amazon | [harvard.edu](http://www.read.seas.harvard.edu/~kohler/class/cs239-w08/decandia07dynamo.pdf) |
+| Data store | **MongoDB** - Document-oriented database | [slideshare.net](http://www.slideshare.net/mdirolf/introduction-to-mongodb) |
+| Data store | **Spanner** - Globally-distributed database from Google | [research.google.com](http://research.google.com/archive/spanner-osdi2012.pdf) |
+| Data store | **Memcached** - Distributed memory caching system | [slideshare.net](http://www.slideshare.net/oemebamo/introduction-to-memcached) |
+| Data store | **Redis** - Distributed memory caching system with persistence and value types | [slideshare.net](http://www.slideshare.net/dvirsky/introduction-to-redis) |
+| | | |
+| File system | **Google File System (GFS)** - Distributed file system | [research.google.com](http://static.googleusercontent.com/media/research.google.com/zh-CN/us/archive/gfs-sosp2003.pdf) |
+| File system | **Hadoop File System (HDFS)** - Open source implementation of GFS | [apache.org](http://hadoop.apache.org/docs/stable/hadoop-project-dist/hadoop-hdfs/HdfsDesign.html) |
+| | | |
+| Misc | **Chubby** - Lock service for loosely-coupled distributed systems from Google | [research.google.com](http://static.googleusercontent.com/external_content/untrusted_dlcp/research.google.com/en/us/archive/chubby-osdi06.pdf) |
+| Misc | **Dapper** - Distributed systems tracing infrastructure | [research.google.com](http://static.googleusercontent.com/media/research.google.com/en//pubs/archive/36356.pdf)
+| Misc | **Kafka** - Pub/sub message queue from LinkedIn | [slideshare.net](http://www.slideshare.net/mumrah/kafka-talk-tri-hug) |
+| Misc | **Zookeeper** - Centralized infrastructure and services enabling synchronization | [slideshare.net](http://www.slideshare.net/sauravhaloi/introduction-to-apache-zookeeper) |
+| | Add an architecture | [Contribute](#contributing) |
+
+### Company architectures
+
+| Company | Reference(s) |
+|---|---|
+| Amazon | [Amazon architecture](http://highscalability.com/amazon-architecture) |
+| Cinchcast | [Producing 1,500 hours of audio every day](http://highscalability.com/blog/2012/7/16/cinchcast-architecture-producing-1500-hours-of-audio-every-d.html) |
+| DataSift | [Realtime datamining At 120,000 tweets per second](http://highscalability.com/blog/2011/11/29/datasift-architecture-realtime-datamining-at-120000-tweets-p.html) |
+| Dropbox | [How we've scaled Dropbox](https://www.youtube.com/watch?v=PE4gwstWhmc) |
+| ESPN | [Operating At 100,000 duh nuh nuhs per second](http://highscalability.com/blog/2013/11/4/espns-architecture-at-scale-operating-at-100000-duh-nuh-nuhs.html) |
+| Google | [Google architecture](http://highscalability.com/google-architecture) |
+| Instagram | [14 million users, terabytes of photos](http://highscalability.com/blog/2011/12/6/instagram-architecture-14-million-users-terabytes-of-photos.html)
[What powers Instagram](http://instagram-engineering.tumblr.com/post/13649370142/what-powers-instagram-hundreds-of-instances) |
+| Justin.tv | [Justin.Tv's live video broadcasting architecture](http://highscalability.com/blog/2010/3/16/justintvs-live-video-broadcasting-architecture.html) |
+| Facebook | [Scaling memcached at Facebook](https://cs.uwaterloo.ca/~brecht/courses/854-Emerging-2014/readings/key-value/fb-memcached-nsdi-2013.pdf)
[TAO: Facebook’s distributed data store for the social graph](https://cs.uwaterloo.ca/~brecht/courses/854-Emerging-2014/readings/data-store/tao-facebook-distributed-datastore-atc-2013.pdf)
[Facebook’s photo storage](https://www.usenix.org/legacy/event/osdi10/tech/full_papers/Beaver.pdf)
[How Facebook Live Streams To 800,000 Simultaneous Viewers](http://highscalability.com/blog/2016/6/27/how-facebook-live-streams-to-800000-simultaneous-viewers.html) |
+| Flickr | [Flickr architecture](http://highscalability.com/flickr-architecture) |
+| Mailbox | [From 0 to one million users in 6 weeks](http://highscalability.com/blog/2013/6/18/scaling-mailbox-from-0-to-one-million-users-in-6-weeks-and-1.html) |
+| Netflix | [A 360 Degree View Of The Entire Netflix Stack](http://highscalability.com/blog/2015/11/9/a-360-degree-view-of-the-entire-netflix-stack.html)
[Netflix: What Happens When You Press Play?](http://highscalability.com/blog/2017/12/11/netflix-what-happens-when-you-press-play.html) |
+| Pinterest | [From 0 To 10s of billions of page views a month](http://highscalability.com/blog/2013/4/15/scaling-pinterest-from-0-to-10s-of-billions-of-page-views-a.html)
[18 million visitors, 10x growth, 12 employees](http://highscalability.com/blog/2012/5/21/pinterest-architecture-update-18-million-visitors-10x-growth.html) |
+| Playfish | [50 million monthly users and growing](http://highscalability.com/blog/2010/9/21/playfishs-social-gaming-architecture-50-million-monthly-user.html) |
+| PlentyOfFish | [PlentyOfFish architecture](http://highscalability.com/plentyoffish-architecture) |
+| Salesforce | [How they handle 1.3 billion transactions a day](http://highscalability.com/blog/2013/9/23/salesforce-architecture-how-they-handle-13-billion-transacti.html) |
+| Stack Overflow | [Stack Overflow architecture](http://highscalability.com/blog/2009/8/5/stack-overflow-architecture.html) |
+| TripAdvisor | [40M visitors, 200M dynamic page views, 30TB data](http://highscalability.com/blog/2011/6/27/tripadvisor-architecture-40m-visitors-200m-dynamic-page-view.html) |
+| Tumblr | [15 billion page views a month](http://highscalability.com/blog/2012/2/13/tumblr-architecture-15-billion-page-views-a-month-and-harder.html) |
+| Twitter | [Making Twitter 10000 percent faster](http://highscalability.com/scaling-twitter-making-twitter-10000-percent-faster)
[Storing 250 million tweets a day using MySQL](http://highscalability.com/blog/2011/12/19/how-twitter-stores-250-million-tweets-a-day-using-mysql.html)
[150M active users, 300K QPS, a 22 MB/S firehose](http://highscalability.com/blog/2013/7/8/the-architecture-twitter-uses-to-deal-with-150m-active-users.html)
[Timelines at scale](https://www.infoq.com/presentations/Twitter-Timeline-Scalability)
[Big and small data at Twitter](https://www.youtube.com/watch?v=5cKTP36HVgI)
[Operations at Twitter: scaling beyond 100 million users](https://www.youtube.com/watch?v=z8LU0Cj6BOU)
[How Twitter Handles 3,000 Images Per Second](http://highscalability.com/blog/2016/4/20/how-twitter-handles-3000-images-per-second.html) |
+| Uber | [How Uber scales their real-time market platform](http://highscalability.com/blog/2015/9/14/how-uber-scales-their-real-time-market-platform.html)
[Lessons Learned From Scaling Uber To 2000 Engineers, 1000 Services, And 8000 Git Repositories](http://highscalability.com/blog/2016/10/12/lessons-learned-from-scaling-uber-to-2000-engineers-1000-ser.html) |
+| WhatsApp | [The WhatsApp architecture Facebook bought for $19 billion](http://highscalability.com/blog/2014/2/26/the-whatsapp-architecture-facebook-bought-for-19-billion.html) |
+| YouTube | [YouTube scalability](https://www.youtube.com/watch?v=w5WVu624fY8)
[YouTube architecture](http://highscalability.com/youtube-architecture) |
+
+# Practice
+## Anki flashcards
+
+
+
+
+
+
+The provided [Anki flashcard decks](https://apps.ankiweb.net/) use spaced repetition to help you retain key system design concepts.
+
+* [System design deck](https://github.com/donnemartin/system-design-primer/tree/master/resources/flash_cards/System%20Design.apkg)
+* [System design exercises deck](https://github.com/donnemartin/system-design-primer/tree/master/resources/flash_cards/System%20Design%20Exercises.apkg)
+* [Object oriented design exercises deck](https://github.com/donnemartin/system-design-primer/tree/master/resources/flash_cards/OO%20Design.apkg)
+
+Great for use while on-the-go.
+
+### Additional system design interview questions
+
+> Common system design interview questions, with links to resources on how to solve each.
+
+| Question | Reference(s) |
+|---|---|
+| Design a file sync service like Dropbox | [youtube.com](https://www.youtube.com/watch?v=PE4gwstWhmc) |
+| Design a search engine like Google | [queue.acm.org](http://queue.acm.org/detail.cfm?id=988407)
[stackexchange.com](http://programmers.stackexchange.com/questions/38324/interview-question-how-would-you-implement-google-search)
[ardendertat.com](http://www.ardendertat.com/2012/01/11/implementing-search-engines/)
[stanford.edu](http://infolab.stanford.edu/~backrub/google.html) |
+| Design a scalable web crawler like Google | [quora.com](https://www.quora.com/How-can-I-build-a-web-crawler-from-scratch) |
+| Design Google docs | [code.google.com](https://code.google.com/p/google-mobwrite/)
[neil.fraser.name](https://neil.fraser.name/writing/sync/) |
+| Design a key-value store like Redis | [slideshare.net](http://www.slideshare.net/dvirsky/introduction-to-redis) |
+| Design a cache system like Memcached | [slideshare.net](http://www.slideshare.net/oemebamo/introduction-to-memcached) |
+| Design a recommendation system like Amazon's | [hulu.com](https://web.archive.org/web/20170406065247/http://tech.hulu.com/blog/2011/09/19/recommendation-system.html)
[ijcai13.org](http://ijcai13.org/files/tutorial_slides/td3.pdf) |
+| Design a tinyurl system like Bitly | [n00tc0d3r.blogspot.com](http://n00tc0d3r.blogspot.com/) |
+| Design a chat app like WhatsApp | [highscalability.com](http://highscalability.com/blog/2014/2/26/the-whatsapp-architecture-facebook-bought-for-19-billion.html)
+| Design a picture sharing system like Instagram | [highscalability.com](http://highscalability.com/flickr-architecture)
[highscalability.com](http://highscalability.com/blog/2011/12/6/instagram-architecture-14-million-users-terabytes-of-photos.html) |
+| Design the Facebook news feed function | [quora.com](http://www.quora.com/What-are-best-practices-for-building-something-like-a-News-Feed)
[quora.com](http://www.quora.com/Activity-Streams/What-are-the-scaling-issues-to-keep-in-mind-while-developing-a-social-network-feed)
[slideshare.net](http://www.slideshare.net/danmckinley/etsy-activity-feeds-architecture) |
+| Design the Facebook timeline function | [facebook.com](https://www.facebook.com/note.php?note_id=10150468255628920)
[highscalability.com](http://highscalability.com/blog/2012/1/23/facebook-timeline-brought-to-you-by-the-power-of-denormaliza.html) |
+| Design the Facebook chat function | [erlang-factory.com](http://www.erlang-factory.com/upload/presentations/31/EugeneLetuchy-ErlangatFacebook.pdf)
[facebook.com](https://www.facebook.com/note.php?note_id=14218138919&id=9445547199&index=0) |
+| Design a graph search function like Facebook's | [facebook.com](https://www.facebook.com/notes/facebook-engineering/under-the-hood-building-out-the-infrastructure-for-graph-search/10151347573598920)
[facebook.com](https://www.facebook.com/notes/facebook-engineering/under-the-hood-indexing-and-ranking-in-graph-search/10151361720763920)
[facebook.com](https://www.facebook.com/notes/facebook-engineering/under-the-hood-the-natural-language-interface-of-graph-search/10151432733048920) |
+| Design a content delivery network like CloudFlare | [figshare.com](https://figshare.com/articles/Globally_distributed_content_delivery/6605972) |
+| Design a trending topic system like Twitter's | [michael-noll.com](http://www.michael-noll.com/blog/2013/01/18/implementing-real-time-trending-topics-in-storm/)
[snikolov .wordpress.com](http://snikolov.wordpress.com/2012/11/14/early-detection-of-twitter-trends/) |
+| Design a random ID generation system | [blog.twitter.com](https://blog.twitter.com/2010/announcing-snowflake)
[github.com](https://github.com/twitter/snowflake/) |
+| Return the top k requests during a time interval | [cs.ucsb.edu](https://www.cs.ucsb.edu/sites/cs.ucsb.edu/files/docs/reports/2005-23.pdf)
[wpi.edu](http://davis.wpi.edu/xmdv/docs/EDBT11-diyang.pdf) |
+| Design a system that serves data from multiple data centers | [highscalability.com](http://highscalability.com/blog/2009/8/24/how-google-serves-data-from-multiple-datacenters.html) |
+| Design an online multiplayer card game | [indieflashblog.com](https://web.archive.org/web/20180929181117/http://www.indieflashblog.com/how-to-create-an-asynchronous-multiplayer-game.html)
[buildnewgames.com](http://buildnewgames.com/real-time-multiplayer/) |
+| Design a garbage collection system | [stuffwithstuff.com](http://journal.stuffwithstuff.com/2013/12/08/babys-first-garbage-collector/)
[washington.edu](http://courses.cs.washington.edu/courses/csep521/07wi/prj/rick.pdf) |
+| Design an API rate limiter | [https://stripe.com/blog/](https://stripe.com/blog/rate-limiters) |
+| Design a Stock Exchange (like NASDAQ or Binance) | [Jane Street](https://youtu.be/b1e4t2k2KJY)
[Golang Implementation](https://around25.com/blog/building-a-trading-engine-for-a-crypto-exchange/)
[Go Implemenation](http://bhomnick.net/building-a-simple-limit-order-in-go/) |
+| Add a system design question | [Contribute](#contributing) |
+
+### Coding Resource: Interactive Coding Challenges
+
+Looking for resources to help you prep for the [**Coding Interview**](https://github.com/donnemartin/interactive-coding-challenges)?
+
+
+
+
+
+
+Check out the sister repo [**Interactive Coding Challenges**](https://github.com/donnemartin/interactive-coding-challenges), which contains an additional Anki deck:
+
+* [Coding deck](https://github.com/donnemartin/interactive-coding-challenges/tree/master/anki_cards/Coding.apkg)
+
+# Additional Resources
+
+## Contributing
+
+> Learn from the community.
+
+Feel free to submit pull requests to help:
+
+* Fix errors
+* Improve sections
+* Add new sections
+* [Translate](https://github.com/donnemartin/system-design-primer/issues/28)
+
+Content that needs some polishing is placed [under development](#under-development).
+
+Review the [Contributing Guidelines](CONTRIBUTING.md).
+
+
+* [Appendix](#appendix)
+ * [Powers of two table](#powers-of-two-table)
+ * [Latency numbers every programmer should know](#latency-numbers-every-programmer-should-know)
+ * [Additional system design interview questions](#additional-system-design-interview-questions)
+ * [Real world architectures](#real-world-architectures)
+ * [Company architectures](#company-architectures)
+ * [Company engineering blogs](#company-engineering-blogs)
+* [Under development](#under-development)
+* [Credits](#credits)
+* [Contact info](#contact-info)
+* [License](#license)
+
## Appendix
You'll sometimes be asked to do 'back-of-the-envelope' estimates. For example, you might need to determine how long it will take to generate 100 image thumbnails from disk or how much memory a data structure will take. The **Powers of two table** and **Latency numbers every programmer should know** are handy references.
@@ -1645,104 +1759,8 @@ Handy metrics based on numbers above:
* [Designs, lessons, and advice from building large distributed systems](http://www.cs.cornell.edu/projects/ladis2009/talks/dean-keynote-ladis2009.pdf)
* [Software Engineering Advice from Building Large-Scale Distributed Systems](https://static.googleusercontent.com/media/research.google.com/en//people/jeff/stanford-295-talk.pdf)
-### Additional system design interview questions
-> Common system design interview questions, with links to resources on how to solve each.
-| Question | Reference(s) |
-|---|---|
-| Design a file sync service like Dropbox | [youtube.com](https://www.youtube.com/watch?v=PE4gwstWhmc) |
-| Design a search engine like Google | [queue.acm.org](http://queue.acm.org/detail.cfm?id=988407)
[stackexchange.com](http://programmers.stackexchange.com/questions/38324/interview-question-how-would-you-implement-google-search)
[ardendertat.com](http://www.ardendertat.com/2012/01/11/implementing-search-engines/)
[stanford.edu](http://infolab.stanford.edu/~backrub/google.html) |
-| Design a scalable web crawler like Google | [quora.com](https://www.quora.com/How-can-I-build-a-web-crawler-from-scratch) |
-| Design Google docs | [code.google.com](https://code.google.com/p/google-mobwrite/)
[neil.fraser.name](https://neil.fraser.name/writing/sync/) |
-| Design a key-value store like Redis | [slideshare.net](http://www.slideshare.net/dvirsky/introduction-to-redis) |
-| Design a cache system like Memcached | [slideshare.net](http://www.slideshare.net/oemebamo/introduction-to-memcached) |
-| Design a recommendation system like Amazon's | [hulu.com](https://web.archive.org/web/20170406065247/http://tech.hulu.com/blog/2011/09/19/recommendation-system.html)
[ijcai13.org](http://ijcai13.org/files/tutorial_slides/td3.pdf) |
-| Design a tinyurl system like Bitly | [n00tc0d3r.blogspot.com](http://n00tc0d3r.blogspot.com/) |
-| Design a chat app like WhatsApp | [highscalability.com](http://highscalability.com/blog/2014/2/26/the-whatsapp-architecture-facebook-bought-for-19-billion.html)
-| Design a picture sharing system like Instagram | [highscalability.com](http://highscalability.com/flickr-architecture)
[highscalability.com](http://highscalability.com/blog/2011/12/6/instagram-architecture-14-million-users-terabytes-of-photos.html) |
-| Design the Facebook news feed function | [quora.com](http://www.quora.com/What-are-best-practices-for-building-something-like-a-News-Feed)
[quora.com](http://www.quora.com/Activity-Streams/What-are-the-scaling-issues-to-keep-in-mind-while-developing-a-social-network-feed)
[slideshare.net](http://www.slideshare.net/danmckinley/etsy-activity-feeds-architecture) |
-| Design the Facebook timeline function | [facebook.com](https://www.facebook.com/note.php?note_id=10150468255628920)
[highscalability.com](http://highscalability.com/blog/2012/1/23/facebook-timeline-brought-to-you-by-the-power-of-denormaliza.html) |
-| Design the Facebook chat function | [erlang-factory.com](http://www.erlang-factory.com/upload/presentations/31/EugeneLetuchy-ErlangatFacebook.pdf)
[facebook.com](https://www.facebook.com/note.php?note_id=14218138919&id=9445547199&index=0) |
-| Design a graph search function like Facebook's | [facebook.com](https://www.facebook.com/notes/facebook-engineering/under-the-hood-building-out-the-infrastructure-for-graph-search/10151347573598920)
[facebook.com](https://www.facebook.com/notes/facebook-engineering/under-the-hood-indexing-and-ranking-in-graph-search/10151361720763920)
[facebook.com](https://www.facebook.com/notes/facebook-engineering/under-the-hood-the-natural-language-interface-of-graph-search/10151432733048920) |
-| Design a content delivery network like CloudFlare | [figshare.com](https://figshare.com/articles/Globally_distributed_content_delivery/6605972) |
-| Design a trending topic system like Twitter's | [michael-noll.com](http://www.michael-noll.com/blog/2013/01/18/implementing-real-time-trending-topics-in-storm/)
[snikolov .wordpress.com](http://snikolov.wordpress.com/2012/11/14/early-detection-of-twitter-trends/) |
-| Design a random ID generation system | [blog.twitter.com](https://blog.twitter.com/2010/announcing-snowflake)
[github.com](https://github.com/twitter/snowflake/) |
-| Return the top k requests during a time interval | [cs.ucsb.edu](https://www.cs.ucsb.edu/sites/cs.ucsb.edu/files/docs/reports/2005-23.pdf)
[wpi.edu](http://davis.wpi.edu/xmdv/docs/EDBT11-diyang.pdf) |
-| Design a system that serves data from multiple data centers | [highscalability.com](http://highscalability.com/blog/2009/8/24/how-google-serves-data-from-multiple-datacenters.html) |
-| Design an online multiplayer card game | [indieflashblog.com](https://web.archive.org/web/20180929181117/http://www.indieflashblog.com/how-to-create-an-asynchronous-multiplayer-game.html)
[buildnewgames.com](http://buildnewgames.com/real-time-multiplayer/) |
-| Design a garbage collection system | [stuffwithstuff.com](http://journal.stuffwithstuff.com/2013/12/08/babys-first-garbage-collector/)
[washington.edu](http://courses.cs.washington.edu/courses/csep521/07wi/prj/rick.pdf) |
-| Design an API rate limiter | [https://stripe.com/blog/](https://stripe.com/blog/rate-limiters) |
-| Design a Stock Exchange (like NASDAQ or Binance) | [Jane Street](https://youtu.be/b1e4t2k2KJY)
[Golang Implementation](https://around25.com/blog/building-a-trading-engine-for-a-crypto-exchange/)
[Go Implemenation](http://bhomnick.net/building-a-simple-limit-order-in-go/) |
-| Add a system design question | [Contribute](#contributing) |
-
-### Real world architectures
-
-> Articles on how real world systems are designed.
-
-
-
-
- Source: Twitter timelines at scale
-
-
-**Don't focus on nitty gritty details for the following articles, instead:**
-
-* Identify shared principles, common technologies, and patterns within these articles
-* Study what problems are solved by each component, where it works, where it doesn't
-* Review the lessons learned
-
-|Type | System | Reference(s) |
-|---|---|---|
-| Data processing | **MapReduce** - Distributed data processing from Google | [research.google.com](http://static.googleusercontent.com/media/research.google.com/zh-CN/us/archive/mapreduce-osdi04.pdf) |
-| Data processing | **Spark** - Distributed data processing from Databricks | [slideshare.net](http://www.slideshare.net/AGrishchenko/apache-spark-architecture) |
-| Data processing | **Storm** - Distributed data processing from Twitter | [slideshare.net](http://www.slideshare.net/previa/storm-16094009) |
-| | | |
-| Data store | **Bigtable** - Distributed column-oriented database from Google | [harvard.edu](http://www.read.seas.harvard.edu/~kohler/class/cs239-w08/chang06bigtable.pdf) |
-| Data store | **HBase** - Open source implementation of Bigtable | [slideshare.net](http://www.slideshare.net/alexbaranau/intro-to-hbase) |
-| Data store | **Cassandra** - Distributed column-oriented database from Facebook | [slideshare.net](http://www.slideshare.net/planetcassandra/cassandra-introduction-features-30103666)
-| Data store | **DynamoDB** - Document-oriented database from Amazon | [harvard.edu](http://www.read.seas.harvard.edu/~kohler/class/cs239-w08/decandia07dynamo.pdf) |
-| Data store | **MongoDB** - Document-oriented database | [slideshare.net](http://www.slideshare.net/mdirolf/introduction-to-mongodb) |
-| Data store | **Spanner** - Globally-distributed database from Google | [research.google.com](http://research.google.com/archive/spanner-osdi2012.pdf) |
-| Data store | **Memcached** - Distributed memory caching system | [slideshare.net](http://www.slideshare.net/oemebamo/introduction-to-memcached) |
-| Data store | **Redis** - Distributed memory caching system with persistence and value types | [slideshare.net](http://www.slideshare.net/dvirsky/introduction-to-redis) |
-| | | |
-| File system | **Google File System (GFS)** - Distributed file system | [research.google.com](http://static.googleusercontent.com/media/research.google.com/zh-CN/us/archive/gfs-sosp2003.pdf) |
-| File system | **Hadoop File System (HDFS)** - Open source implementation of GFS | [apache.org](http://hadoop.apache.org/docs/stable/hadoop-project-dist/hadoop-hdfs/HdfsDesign.html) |
-| | | |
-| Misc | **Chubby** - Lock service for loosely-coupled distributed systems from Google | [research.google.com](http://static.googleusercontent.com/external_content/untrusted_dlcp/research.google.com/en/us/archive/chubby-osdi06.pdf) |
-| Misc | **Dapper** - Distributed systems tracing infrastructure | [research.google.com](http://static.googleusercontent.com/media/research.google.com/en//pubs/archive/36356.pdf)
-| Misc | **Kafka** - Pub/sub message queue from LinkedIn | [slideshare.net](http://www.slideshare.net/mumrah/kafka-talk-tri-hug) |
-| Misc | **Zookeeper** - Centralized infrastructure and services enabling synchronization | [slideshare.net](http://www.slideshare.net/sauravhaloi/introduction-to-apache-zookeeper) |
-| | Add an architecture | [Contribute](#contributing) |
-
-### Company architectures
-
-| Company | Reference(s) |
-|---|---|
-| Amazon | [Amazon architecture](http://highscalability.com/amazon-architecture) |
-| Cinchcast | [Producing 1,500 hours of audio every day](http://highscalability.com/blog/2012/7/16/cinchcast-architecture-producing-1500-hours-of-audio-every-d.html) |
-| DataSift | [Realtime datamining At 120,000 tweets per second](http://highscalability.com/blog/2011/11/29/datasift-architecture-realtime-datamining-at-120000-tweets-p.html) |
-| Dropbox | [How we've scaled Dropbox](https://www.youtube.com/watch?v=PE4gwstWhmc) |
-| ESPN | [Operating At 100,000 duh nuh nuhs per second](http://highscalability.com/blog/2013/11/4/espns-architecture-at-scale-operating-at-100000-duh-nuh-nuhs.html) |
-| Google | [Google architecture](http://highscalability.com/google-architecture) |
-| Instagram | [14 million users, terabytes of photos](http://highscalability.com/blog/2011/12/6/instagram-architecture-14-million-users-terabytes-of-photos.html)
[What powers Instagram](http://instagram-engineering.tumblr.com/post/13649370142/what-powers-instagram-hundreds-of-instances) |
-| Justin.tv | [Justin.Tv's live video broadcasting architecture](http://highscalability.com/blog/2010/3/16/justintvs-live-video-broadcasting-architecture.html) |
-| Facebook | [Scaling memcached at Facebook](https://cs.uwaterloo.ca/~brecht/courses/854-Emerging-2014/readings/key-value/fb-memcached-nsdi-2013.pdf)
[TAO: Facebook’s distributed data store for the social graph](https://cs.uwaterloo.ca/~brecht/courses/854-Emerging-2014/readings/data-store/tao-facebook-distributed-datastore-atc-2013.pdf)
[Facebook’s photo storage](https://www.usenix.org/legacy/event/osdi10/tech/full_papers/Beaver.pdf)
[How Facebook Live Streams To 800,000 Simultaneous Viewers](http://highscalability.com/blog/2016/6/27/how-facebook-live-streams-to-800000-simultaneous-viewers.html) |
-| Flickr | [Flickr architecture](http://highscalability.com/flickr-architecture) |
-| Mailbox | [From 0 to one million users in 6 weeks](http://highscalability.com/blog/2013/6/18/scaling-mailbox-from-0-to-one-million-users-in-6-weeks-and-1.html) |
-| Netflix | [A 360 Degree View Of The Entire Netflix Stack](http://highscalability.com/blog/2015/11/9/a-360-degree-view-of-the-entire-netflix-stack.html)
[Netflix: What Happens When You Press Play?](http://highscalability.com/blog/2017/12/11/netflix-what-happens-when-you-press-play.html) |
-| Pinterest | [From 0 To 10s of billions of page views a month](http://highscalability.com/blog/2013/4/15/scaling-pinterest-from-0-to-10s-of-billions-of-page-views-a.html)
[18 million visitors, 10x growth, 12 employees](http://highscalability.com/blog/2012/5/21/pinterest-architecture-update-18-million-visitors-10x-growth.html) |
-| Playfish | [50 million monthly users and growing](http://highscalability.com/blog/2010/9/21/playfishs-social-gaming-architecture-50-million-monthly-user.html) |
-| PlentyOfFish | [PlentyOfFish architecture](http://highscalability.com/plentyoffish-architecture) |
-| Salesforce | [How they handle 1.3 billion transactions a day](http://highscalability.com/blog/2013/9/23/salesforce-architecture-how-they-handle-13-billion-transacti.html) |
-| Stack Overflow | [Stack Overflow architecture](http://highscalability.com/blog/2009/8/5/stack-overflow-architecture.html) |
-| TripAdvisor | [40M visitors, 200M dynamic page views, 30TB data](http://highscalability.com/blog/2011/6/27/tripadvisor-architecture-40m-visitors-200m-dynamic-page-view.html) |
-| Tumblr | [15 billion page views a month](http://highscalability.com/blog/2012/2/13/tumblr-architecture-15-billion-page-views-a-month-and-harder.html) |
-| Twitter | [Making Twitter 10000 percent faster](http://highscalability.com/scaling-twitter-making-twitter-10000-percent-faster)
[Storing 250 million tweets a day using MySQL](http://highscalability.com/blog/2011/12/19/how-twitter-stores-250-million-tweets-a-day-using-mysql.html)
[150M active users, 300K QPS, a 22 MB/S firehose](http://highscalability.com/blog/2013/7/8/the-architecture-twitter-uses-to-deal-with-150m-active-users.html)
[Timelines at scale](https://www.infoq.com/presentations/Twitter-Timeline-Scalability)
[Big and small data at Twitter](https://www.youtube.com/watch?v=5cKTP36HVgI)
[Operations at Twitter: scaling beyond 100 million users](https://www.youtube.com/watch?v=z8LU0Cj6BOU)
[How Twitter Handles 3,000 Images Per Second](http://highscalability.com/blog/2016/4/20/how-twitter-handles-3000-images-per-second.html) |
-| Uber | [How Uber scales their real-time market platform](http://highscalability.com/blog/2015/9/14/how-uber-scales-their-real-time-market-platform.html)
[Lessons Learned From Scaling Uber To 2000 Engineers, 1000 Services, And 8000 Git Repositories](http://highscalability.com/blog/2016/10/12/lessons-learned-from-scaling-uber-to-2000-engineers-1000-ser.html) |
-| WhatsApp | [The WhatsApp architecture Facebook bought for $19 billion](http://highscalability.com/blog/2014/2/26/the-whatsapp-architecture-facebook-bought-for-19-billion.html) |
-| YouTube | [YouTube scalability](https://www.youtube.com/watch?v=w5WVu624fY8)
[YouTube architecture](http://highscalability.com/youtube-architecture) |
### Company engineering blogs