1. Cataclysm: Handling Extreme Overloads in Internet Services
Bhuvan Urgaonkar and Prashant Shenoy
University of Massachusetts Amherst
Good morning. I am Bhuvan Urgaonkar from UMASS Amherst. The title of my paper is … This is joint work with my advisor PS and Timothy Roscoe from Intel Reserach.

2. Overloads in Internet Applications
Bottleneck!
Ecommerce app
Internet apps experience overloads
E.g. 20 fold increase in CNN traffic on 9/11
Goal: Handle overloads without app downtime
Let me begin by providing the motivation behind this work. During the past few years there has been a proliferation of Internet applications. Examples of such applications include ecommerce applications, streaming media servers, online game servers etc. Due to falling hardware prices and improvements in networking technology, clusters of commodity servers have become a popular alternative to large multiprocessors for hosting these applications.
Key idea: Scalable policing & provisioning

3. Cataclysm Components Provisioner: Queuing theoretic app models
Add servers to overloaded apps
Policer: Differentiated service and scalability
Admit important requests during overload
d2 > d1 d1
Admitted d2
Admission Control
Dropped
Classifier
Switch to approx. admission control at high loads
Even higher loads => multiple sentries, DNS RR

4. Cataclysm Policer Admits important requests during overloads
Admitted requests see good response time
Arrival rate 50
100
150
200
250
300
400
500
600
Time (sec)
GLD
SIL
BRZ
Fraction admitted
0.2
0.4
0.6
0.8 1
1.2
100
200
300
400
500
600
Time (sec)
GLD
SIL
BRZ
Single policer: arrival rates upto 19,000 req/s
Can add more policers at higher loads

5. Concluding Remarks The Cataclysm hosting platform
Scalable policer
Dynamic provisioning of servers
Implementation on Linux cluster of size 20
Experimentation with variety of workloads

6. More information:
Thank you!