Skip to content

Latest commit

 

History

History
86 lines (72 loc) · 2.54 KB

README.md

File metadata and controls

86 lines (72 loc) · 2.54 KB

DebuggingDemos

Demos for .NET Debugging Presentations

If you came here looking for debugging info or labs, check out my blog https://www.tessferrandez.com

Preparations

  1. Install DebugDiag
  2. Install ProcDump
  3. Install WinDbg
  4. Download and compile Netling easy load tester
  5. In WinDbg, Set the sympath to srv*c:\symcache*https://msdl.microsoft.com/download/symbols and save workspace

Use magnifier with bar to manify command in windbg

Capture demo dumps

  1. Crash - Presidents demo - next on Obama
  2. Crash - MyShop - Contact - Email=Test --- need to capture with a debug diag rule, dump on first chance stack overflow
  3. Hang - MyShop - Products - Netling 8/10/1 (can take with taskmanager if you set up vdir in real IIS 64 bit)
  4. Memory - MyShop - News - Netling 4/10/1 (take one baseline before and one leak after)

Script

Dump walkthrough

  1. Open crash 1 in WinDbg

  2. Add commands to scratchpad

  3. Walk through commands and explain what we can find in a memory dump

       ~* kb
   .loadby sos clr
   !clrstack
   !dso
   !do <exception>
   !objsize <exception>
   !click <message>
   !gcroot <message>
   lm
   !eeheap -gc
   !dumpheap -stat

Crash 1

  1. Repro crash in presidents - next on Obama
  2. Procdump -ma ThePresidents.exe -e
  3. in Windbg !clrstack and !dso
  4. Open in Debug Diag
  • exception on stack 0
  • stack of T0
  • previous exceptions
  • discuss SOF/OOM/EE
  1. Open in Visual Studio (managed)
  2. Open event viewer

(*) debug diag rules

Hang 1

  1. Browse to Products (MyShop)
  2. Netling 8/10/1 + task manager (check CPU)
  3. Netling again - dump with task manager (*) Windbg - show lots of same stacks
  4. Debug Diag
  • show wait
  • http context report
  1. Visual studio (Mixed??)
  • Parallel stacks

Hang 2

  1. Open presidents, show slowness on next
  2. Analyze/Performance Profiler
  • Performance wizard
  • Instrumentation
  1. Repro / Stop profiling
  2. Summary - App.Run - move down path

Memory 1

  1. Browse news
  2. dump for comparison
  3. Netling 4/10/1
  4. Dump leak
  5. Open in VS
  • sort by size diff bytes
  • newscontroller root down
  1. Open in Debug Diag
  • see cache

(*) open in Windbg and debug with !gcroot etc.

Slides available on my Slideshare