2. About Us
Company Profile
• Founded 2007 Key Stats
• Tier 1 venture-backed • Launched April 2008
• Experienced team of eleven in • Mobile website (no
Needham, MA download required),
iPhone web/app, Internet
• Developer of direct-to-consumer
mobile services • 1.5+ million unique
visitors / month
• 15+ million monthly page
SnapMyLife Service views (Aug 2008)
• Mobile photo sharing community • Over 90% traffic from
mobile devices
• Best mobile user experience
• Visitors from every
• Premium demographic country in the world
• Rapidly growing local & global • 400,000+ registered users
audience
2
4. Overview
EC2
• Entire web serving stack
• Daemons for background/batch processing
• Internal infrastructure
S3
• Cheap CDN
• Backups for EC2
Mechanical Turk
• Content filtering
• Content classification
4
5. EC2 Costs
Xen based cluster on leased hardware
• Time sink
• Not as flexible
• Slow to provision (Days vs Minutes)
• More expensive (~$1.8K/month)
EC2/S3
• We hardly ever think about it, just use it
• Unlimited playground without fear of breakage
• Clone your entire production stack in minutes
• Works out cheaper (~$1.2K/month)
5
6. EC2/S3 Architecture
Fairly standard architecture
DNS – Web – App – Memcached - Mysql
Assume and plan for failure
Use a role based architecture to easily scale
roles independently of each other (e.g. add
an app server or db slave)
Roles scale in as well as out – incredibly
useful to have production cloned to a single
instance for testing new features.
6
7. EC2 Instance Allocation
Static Vs Dynamic instance allocation
• We went static route
• Our traffic graph pretty flat due to global nature
• Easier, dynamic cost savings not worth the extra
complexity for us
• We watch our load carefully, given a critical alert, we
can scale up in a matter of minutes by increasing the
instance count for the impacted roles.
All instance configuration lives in our source tree.
New instances to handle any combination of roles is
only a couple of commands and a few minutes away
We open sourced our framework for doing so: The
rubber project on github -
http://github.com/wr0ngway/rubber/wikis
7
8. Mechanical Turk
All of our content gets classified through turk
Some of our content gets tagged
We interact with turk solely through
automation – large quantities preclude use
of web interface
Results were better than anticipated
Incredibly quick turnaround, 24x7
Very hard to match this performance given
the hiring constraints of a startup
8
9. Mturk costs
Depends a lot on how you do it
Keep questions simple, pay less
Multiple questions, better result
Example of a months usage
• ~64K picture moderations (x3)
• ~28K pictures tagged
• Total Cost ~$3.3K (AWS commission $1.1K)
9
10. Things we’d like to see
A reliable way to send mail from EC2
Faster S3 response - New AWS CDN
should address this
Automatic billing for Mturk
A better plan for large volume mturk usage –
commission is normally 10%, but the half
cent minimum makes it 50% if all you do
are 1c HITs
10
