1. Death of a Web Server Richard Campbell Strangeloop Networks richard@strangeloopnetworks.com

2. Richard Campbell Background –First laid hands on a microcomputer in 1977, its been downhill since then –Spent the last 15 years helping companies scale applications on a variety of platforms Currently –Co-Founder and Chief Evangelist of Strangeloop Networks –Co-Host of.NET Rocks! –Host of RunAs Radio!

3. Agenda Setting the Stage Testing the Web Site Instrumenting a Web Server Instrumenting and Analyzing Caching Actually Solving the Problem

4. Setting the Stage The Portable Data Center –Load Test Machine –Web Server –Database Server Software –Windows 2008 Server 64 bit –Visual Studio 2008 Test Edition

5. Testing the Web Site Building Good Tests –Know reality! Get log data Different kinds of load tests –Test to failure –Soak test

6. Instrumenting a Web Server Perf Mon is your friend! –CPU Utilization –Requests per Second –Requests Queued –Bytes in the.NET Heap

7. Instrumenting Caching Log every time: –A cache item gets populated –A cache item is destroyed –A cache item gets used

8. Actually Fixing the Problem Don’t cache what doesn’t get reused! Choices: –Don’t cache datasets with unbounded parameters –Bound the parameters

9. Summary Diagnosis is the most challenging part of the process Use facts – instrument everything! Theorize probable cause, then prove it Consider a variety of solutions