1. Inktomi Confidential and Proprietary The Inktomi Climate Lab: An Integrated Environment for Analyzing and Simulating Customer Network Traffic Stephane Gigandet, Ashok Sudarsanam, and Anshu Aggarwal Inktomi Corporation Foster City, CA ACM SIGCOMM Internet Measurement Workshop 2001

2. Inktomi Confidential and Proprietary Motivation Inktomi Traffic Server is our web-caching product. Some software issues occurring at customer sites are difficult to reproduce in-house. The traffic is different at every customer site. Software issues take longer to reproduce and fix.

3. Inktomi Confidential and Proprietary Solution: The Inktomi Climate Lab An environment to analyze and simulate the HTTP traffic of customer deployments. Used for: Stress-testing our product before it is deployed Reproducing software issues that occur in the field Estimating performance Consists of 3 components: A log analysis tool : Loggen A load generation tool : Loadgen Dedicated hardware Named after agricultural laboratories that can replicate any climate in the world to test seeds.

4. Inktomi Confidential and Proprietary Inktomi Climate Lab Inktomi Traffic Servers Loadgen servers Loadgen clients Customer Deployment Internet Inktomi Traffic Servers Users Design Loggen logs Loadgen test plan

5. Inktomi Confidential and Proprietary Log Analysis Tool: Loggen Analyzes customers logs Logs are collected using Traffic Server Logs include IP addresses, methods, URLs, all headers, status codes, numbers of bytes transferred and timing information. Outputs a test plan containing distributions XML file used to configure the Load Generation Tool Example of distributions : document size, site popularity, number of clicks per session, requests per click etc.

6. Inktomi Confidential and Proprietary Load Generation Tool: Loadgen Simulates both clients and servers Uses test plans generated manually or with Loggen Models individual client sessions realistically Implements all the HTTP/1.1 features Supports every request method, header and response status code Keeps state (cookies) Simulates network conditions at the application level

7. Inktomi Confidential and Proprietary Experimental results Deployments: - Customer A: 3 million ops during 2 hours. - Customer B: 2 million ops during 24 hours. - Customer C: 330,000 ops during 24 hours Resulting test plans are currently used to help stress test our product. Customer A Customer B Customer C

8. Inktomi Confidential and Proprietary Validation of the simulation Reproduction of old bugs first reported by customers Quantification of code coverage Logs collected during the simulation should result in a test plan similar to the test plan used during the simulation. Inktomi Traffic Servers Loadgen servers Loadgen clients Initial Loadgen test plan Loggen logs Resulting Loadgen test plan

9. Inktomi Confidential and Proprietary Conclusion The Climate Lab reproduces customer environments Loggen converts logs to test plans Loadgen uses test plans to reproduce traffic Next: evaluation of the accuracy of the simulation The Climate Lab is used in-house to uncover software issues and test the stability of our web caching proxy