1. Production debugging of SharePoint
applications
#SPSBEUK
Wouter van Vugt
April 26th, 2014

2. Thanks to our sponsors!
Gold
Silver

3. Agenda

5. .NET Applications
OS
CLR
App

6. Common Language Runtime
Operation
• Memory management
• Thread synchronization
• Error handling
• Type Safety
Security
• Code Access Security
• Data Execution
Prevention (OS)
• Address Space Layout
Randomization (OS)
Execution
• Intermediate
Language

7. Type Safety
Car c = new Person()
‘Pointer type’ Pointer Object type

8. Circumventing type safety
Demo

9. Creating .NET Applications
C#, C++,
VB.NET,
F#.... (40+)
Module
PDB
Compile Link
Assembly
PDB

10. Executing code
C#
Machine
Code
Language richness compared
IL

11. Executing code with JIT Compilation
Console.WriteLine("Hi");
Console.WriteLine("There");
JIT Compiler
-Lookup IL for method
-Compile IL to native
-Modify metadata to
point to compiled code
-Jump to compiled
code
Console metadata
static void
WriteLine(string)
JIT Compiler Address
static void WriteLine()
JIT Compiler Address
Native CPU
Instructions
Native Address

12. Executing code with JIT Compilation
Console.WriteLine("Hi");
Console.WriteLine("There");
Console metadata
static void
WriteLine(string)
JIT Compiler
-Lookup IL for method
-Compile IL to native
-Modify metadata to
point to compiled code
-Jump to compiled code
Native Address
static void WriteLine()
JIT Compiler Address
Native CPU
Instructions

13. Code optimization

14. Running non optimized code

15. C# Compiler – Variable Generation

16. C# Compiler – Variable Generation

17. C# Compiler – Inserting NOP

18. C# Compiler – Inserting NOP

19. C# Compiler – Branching

20. C# Compiler – Branching

21. Compile time
optimizations
Demo

22. Just In Time Compilation
Compiler switch C# IL Code Quality JIT Native Code Quality
/optimize- /debug- Unoptimized Optimized
/optimize- /debug+ Unoptimized Unoptimized
/optimize+ /debug+ Optimized Optimized

23. NGEN.exe

24. JIT - Local variable elimination
PrintUser(GetUser(3));
Before
After

25. JIT – Range check elimination
static int[] _array = new int[10];
static volatile int _i;
static void Main(string[] args)
{
int[] localRef = _array;
for (int i = 0; i < localRef.Length; ++i)
_i += localRef[i];
}
Before
After

26. JIT – Method Inlining
public class Program {
static void Main(string[] args) {
int i = 5 & 4;
}
}
Before
After

27. JIT – Tail Call Optimization
static void Main(string[] args)
{
TestTailCallOptimization();
}
public static void TestTailCallOptimization()
{
string s = "Test";
TailCall1(s);
}
static void TailCall1(string s)
{
Console.WriteLine(s);
TailCall2(s);
}
static void TailCall2(string s)
{
Console.WriteLine(s + s);
}

28. Native NGEN images are hard to debug
Loading non-precompiled assemblies
C:> SET COMPLUS_ZAPDISABLE=1
C:> NGEN uninstall MyAssembly

29. Preventing JIT optimization
[.NET Framework Debugging Control]
GenerateTrackingInfo=1
AllowOptimize=0
[assembly: Debuggable(DebuggableAttribute.DebuggingModes.DisableOptimizations |
DebuggableAttribute.DebuggingModes.EnableEditAndContinue |
DebuggableAttribute.DebuggingModes.IgnoreSymbolStoreSequencePoints |
DebuggableAttribute.DebuggingModes.Default)]

30. Debugging optimized
code
Demo

31. Debugging code

32. PDB Files

33. Symbol Servers

34. Locating debug symbols
MyAssembly.dll MyAssembly.pdb
GUID GUID
Equal

35. Dumpbin.exe

36. Prevent loading all PDBs

37. Visual Studio Source Server support

38. Configuring Symbol Locations

39. PDB alternate streams

40. SYMBOL SERVERS, SOURCE SERVERS AND
SOURCE INDEXING
Demo

41. Working with break points

42. Setting breakpoints on automatic
properties

43. Breakpoints on automatic properties

44. Debugging third party code

45. Enabling remote debugging

46. Debugging SharePoint
Demo

47. Thank you!