Twitter Rules!
Sugree Phatanapherom
sugree@gmail.com
http://sugree.com/

Twitter
 Social messaging service
 140 characters
 Follow friends
 Notification – gtalk, sms
 Open APIs
 My twitter – http://twitter.com/sugree
 Clients – Twitterific, TwitterFox, Snitter, Spaz,
Tweetr, TinyTwitter, Jitter

Behind Twitter
 Ruby on Rails
 Mongrel cluster
 Starling MemCache
 Master/slave MySQL
 Erlang ejabberd

Stability?
 Twitter is stable as long as there is no big
event, e.g., MacWorld 2008
 In other words, it is scalability issue!

Scale of Twitter
 Assumption #1
 10,000 users
 1 update/hour = 3 req/sec
 3 minutes refresh interval = 55 req/s
 Assumption #2
 100,000 users
 1 update/hour = 27 req/sec
 3 minutes refresh interval = 555 req/s

BitTorrent Tracker
 Assumption #1
 10,000 users
 30 minutes announce interval = 8 req/s
 Assumption #2
 100,000 users
 30 minutes announce interval = 83 req/s

Fact Apr 2007
 http://www.slideshare.net/al3x/scaling-twitter-
railsconf-2007
 200-300 req/s
 Spike at 800 req/s
 Peak at 11,000 req/s
 2,400 queries/s

Fact Apr 2007
 Mongrels 19 cores
 Message queue 16 cores
 Jabber 2 cores
 MySQL 8 cores (single box)
 16+ GB MemCache
 32 cores total

Why Twitter?
 E-mail
 Leave messages in mailbox
 Wait for read/reply or
 Call/SMS/IM to notify
 IM
 Wait for online
 Twitter
 Tweet to IM, to SMS and/or to e-mail

IRC and Twitter
 Per channel  Broadcast
broadcast  Follow
 Join/part/kick/ban +on/_/off/unfollow
 Direct message  Direct message
 On-line only  Always on-line
 Web  Web
 IM  IM
 Client  SMS
 APIs

What are actually in Twitter?
 What are your friends doing?
 Thoughts
 Questions
 Answers
 Opinions
 etc...

Fun to
 Follow friends
 Ask and reply on the road
 Get reply promptly
 Track words

How to Twitter
 Go to http://twitter.com/
 Sign up
 Bind your gtalk and twitter@twitter.com
 Bind your phone
 Charge rate depends on your career
 True Move – receive free / send 9 baht

Add-on services
 http://twitterfeed.com/
 http://www.loudtwitter.com/
 http://twitternotes.com/
 http://twittercal.com/
 http://twittervision.com/

Clients
 AIR – Spaz, Snitter, Tweetr
 Firefox – Tweetbar, TwitterFox
 Gnome – gTwitter
 J2ME – TinyTwitter, Jitter
 iPhone – Thincloud, Hahlo
 Binding – Python, Ruby, PHP

Wanna try?
 The best way to understand the power of
Twitter is to give it a try
 Bind gtalk
 And ”follow sugree”