This is what worked for me: Download the following DLLs: clr.dll mscordacwks.dll SOS.dll from this folder on the machine that generated the dump: C:\Windows\Microsoft.NET\Framework64\v4.0.30319 Run the following command. The path to SOS.DLL should be without quotes, unescaped path delimiters: .load path to downloaded SOS.DLL I think a new WinDbg session is required for this to … Read more
The CLR runtime dll was renamed to clr.dll with .NET 4. So in order to load the correct version of SOS you need to adjust your .loadby command. I.e. .loadby sos clr Also, if you’re on 64 bit, you should install the 32 bit version of Debugging Tools for Windows as well in order to … Read more
Windbg is not the right tool for this job. Dumps are only snapshots so you have no idea what happened before. Use ETW and here the CPU Sampling, which sums all calls and shows you in detail the CPU usage. Install the Windows Performance Toolkit which is part of the Windows 10 SDK (V1607 works … Read more
Async pinned handles are strongly correlated with overlapped I/O in Windows. Which supports asynchronous reading and writing with ReadFile and WriteFile, using the OVERLAPPED argument. The device driver stores the passed buffer pointer and directly reads/writes from/to the buffer, entirely asynchronously from the program’s operation. The managed wrapper methods are BeginRead and BeginWrite. If the … Read more
There are a several things to know when setting up a symbol server and/or symbol network share. WinDbg symbol load order Symbols are searched in the symbol path from the beginning to the end, i.e. in the symbol path C:\a;C:\b, it will first look in C:\a and then in C:\b. While this does not really … Read more
Here are some general steps that will get you on your way: First, you must change your compiler’s settings so that it creates PDB files, even for release builds. Later versions of the Visual C++ compiler do this by default, but in many versions of Visual C++ you must do this yourself. Create program database … Read more
Here’s the graph that I use for deciding about .NET OutOfMemoryExceptions: For the !u part, I know two options so far. The first is the creation of a big array of objects. See How to identify array type for details. The second is throwing an OutOfMemoryException directly, which you would identify like this: 0:000> .symfix … Read more
The CLR uses the LOH to preallocate a few objects (such as the array used for interned strings). Some of these are less than 85000 bytes and thus would not normally be allocated on the LOH. It is an implementation detail, but I assume the reason for this is to avoid unnecessary garbage collection of … Read more
Why is bitness relevant here? The bitness matters for .NET applications for the following reasons: a DAC (data access control) library (mscordakwks.dll) of the correct bitness is needed. There’s no cross-bitness DAC available. the debugger needs to be able to load the SOS debugging extension of the correct bitness It is not possible to convert … Read more
Symbols can be set up correctly in various different ways. WARNING: The examples here use \\server\symbols which is typically a network storage that is not available. Adapt it to your local server or leave that part out completely if you don’t have one. A non-existent server may cause delays etc. TLDR version for 80% of … Read more