Performance in .NET: Best practices Vlad Balan, Sorin Oboroceanu www.rms.ro

1. Performance in .NET: Best practices Sorin Oboroceanu, obs@rms.ro Vlad Balan, bav@rms.ro RomSoft, www.rms.ro Iași, 8th of May 2010

2. Agenda Why performance matters Serialization Reading XML Garbage Collection JITing

3. Why performance matters Everyone loves performance Performance=money Bing - 2 seconds slower – 4.3% drop in revenue Google – 400ms slower – 0.6% drop in searches Yahoo! – 400ms slower – 5-9% drop in full page traffic Mozilla – 2.2 seconds faster – increased download conversion 15.4% Site speed is now taken into account in search rankings

4. Why performance matters Better apps – Satisfied customers

5. Our Demo APP Uses StackOverflow.com’s data Groups users by location Displays user locations in a chart Will work in a client/server architecture Has performance issues 

6. Collections Groupping data List<T> LINQ to Objects Dictionary<T,V> DEMO

7. Client-Server communication Retrieving all users on the client Grouping data List<T> LINQ to Objects Dictionary<T,V> DEMO

8. Client-Server communication Grouping data on the server List<T> LINQ to Objects Dictionary<T,V> Retrieving only location-related data on the client DEMO

9. Reading XML DataSet XmlReader LINQ to XML XmlDocument DEMO

10. Garbage Collection Why memory matters Garbage Collector Object Finalization

11. Why memory matters Inefficient use of memory can impact Performance Stability Scalability Other Applications Hidden problems in code can cause Memory Leaks Excessive memory usage Unnecessary performance overhead

12. .NET Memory Management Small Object Heap (SOH) – Objects < 85K Large Object Heap (LOH) – Objects => 85K

13. Small Object Heap (SOH) GC SmallObjectObjectA = new SmallObject(); SmallObjectObjectB = new SmallObject(); Global Objects Small Object Heap Next Object Pointer ObjectE Next Object Pointer Stack ObjectD Static Objects Next Object Pointer ObjectC Next Object Pointer ObjectB ObjectB Next Object Pointer ObjectA Root Reference ObjectA Next Object Pointer Child Reference

14. Generations GC - Gen 0 GC - Gen 1 GC - Gen 2 Small Object Heap Gen 0 Next Object Pointer Global Objects ObjectD ObjectC Next Object Pointer Gen 1 Static Objects Stack ObjectB Gen 2 Root Reference ObjectA

15. Large Object Heap (LOH) GC- Gen2 LargeObjectObjectD= new LargeObject(); Global Objects Free space table Large Object Heap 5727400 425000 16777216 ObjectD 94208 182272 Free space Stack ObjectC ObjectC ObjectB Free space ObjectB ObjectA ObjectA

16. Finalization GC Finalization Queue FinObjectObjectE = new FinObject(); Small Object Heap Gen 0 Global Objects ObjectE ObjectE Finalize() ObjectD fReachable Queue Finalizer thread ObjectC Stack Gen 1 ObjectB ObjectB ObjectA ObjectA

17. Finalization public class Test { ~Test() { Cleanup (); } private void Cleanup() {// clean up unmanaged resources } }

18. Disposable pattern public class Test : IDisposable{ ~Test() { Cleanup (false); } private void Cleanup(boolcodeDispose) { if (codeDispose) { // dispose managed resources } // clean up unmanaged resources } public void Dispose() { Cleanup (true); GC.SuppressFinalize(this); } }

19. DEMO

20. JITing Console static void WriteLine(); static void WriteLine(string); (remaining members) Managed EXE static void Main(){ Console.WriteLine(“Hello”); Console.WriteLine(“GoodBye”); } JITCompiler JITCompiler MSCorEE.dll … JITCompiler function{ Look up the called method in the metadata Get the IL for it from metadata Allocate memory Compile the IL into allocated memory Modify the method’s entry in the Type’s table so it points to allocated memory Jump to the native code contained inside the memory block. } Native CPU instr.

21. JITing Console static void WriteLine(); static void WriteLine(string); (remaining members) Managed EXE static void Main(){ Console.WriteLine(“Hello”); Console.WriteLine(“GoodBye”); } JITCompiler Native MSCorEE.dll … JITCompiler function{ Lookup the called method in the metadata Get the IL for it from metadata Allocate memory Compile the IL into allocated memory Modify the method’s entry in the Type’s table so it points to allocated memory Jump to the native code contained inside the memory block.} Native CPU instr.

22. DEMO

23. Resources CLR via C# 3, Jeffrey Richter www.red-gate.com www.stackoverflow.com

24. Q&A

25. Please fill the evaluation formThank you very much! Sorin Oboroceanu, obs@rms.ro Vlad Balan, bav@rms.ro RomSoft, www.rms.ro Iași, 8th of May 2010