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# Steps to reproduce
Build a very large iOS app, with a lot of code, which produces a very large mdb file (> 2.5MB)
# Expected behavior
Breakpoint can be set.
# Actual behavior
OOM when placing a breakpoint.
# Supplemental info (logs, images, videos)
Microsoft Visual Studio
EXCEPTION: System.OutOfMemoryException: Exception of type 'System.OutOfMemoryException' was thrown.
at Mono.Debugging.Soft.SoftDebuggerSession.LoadMdbFile(String mdbFileName)
at Mono.Debugging.Soft.SoftDebuggerSession.CheckBetterMatch(TypeMirror type, String file, Int32 line, Int32 column, Location found)
at Mono.Debugging.Soft.SoftDebuggerSession.FindLocationByMethod(MethodMirror method, String file, Int32 line, Int32 column, Boolean& insideTypeRange)
at Mono.Debugging.Soft.SoftDebuggerSession.FindLocationByType(TypeMirror type, String file, Int32 line, Int32 column, Boolean& genericMethod, Boolean& insideTypeRange)
at Mono.Debugging.Soft.SoftDebuggerSession.ResolveBreakpoints(TypeMirror type)
at Mono.Debugging.Soft.SoftDebuggerSession.HandleTypeLoadEvents(TypeLoadEvent events)
at Mono.Debugging.Soft.SoftDebuggerSession.HandleEventSet(EventSet es)
# Test environment (full version information)
Microsoft Visual Studio Enterprise 2017 RC
Version 15.0.26014.0 D15REL
Microsoft .NET Framework
Installed Version: Enterprise
Architecture Diagrams and Analysis Tools 00369-50000-00000-AA875
Microsoft Architecture Diagrams and Analysis Tools
Visual Basic 2017 RC 00369-50000-00000-AA875
Microsoft Visual Basic 2017 RC
Visual C# 2017 RC 00369-50000-00000-AA875
Microsoft Visual C# 2017 RC
Visual C++ 2017 RC 00369-50000-00000-AA875
Microsoft Visual C++ 2017 RC
Visual F# 4.1 00369-50000-00000-AA875
Microsoft Visual F# 4.1
Application Insights Tools for Visual Studio Package 8.4.01118.2
Application Insights Tools for Visual Studio
ASP.NET and Web Tools 2016 15.0.21206.0
ASP.NET and Web Tools 2016
ASP.NET Web Frameworks and Tools 2013 5.2.41123.0
For additional information, visit https://www.asp.net/
Azure App Service Tools v2.9.6 15.0.21130.0
Azure App Service Tools v2.9.6
Command Bus, Event Stream and Async Manager Merq
Provides ICommandBus, IEventStream and IAsyncManager MEF services for loosely coupled Visual Studio extension components communication and integration.
Common Azure Tools 1.8
Provides common services for use by Azure Mobile Services and Microsoft Azure Tools.
A Visual Studio Extension that brings the GitHub Flow into Visual Studio.
KofePackagePackage Extension 1.0
KofePackagePackage Visual Studio Extension Detailed Info
Microsoft Continuous Delivery Tools for Visual Studio 0.1
Simplifying the configuration of continuous build integration and continuous build delivery from within the Visual Studio IDE.
Microsoft MI-Based Debugger 1.0
Provides support for connecting Visual Studio to MI compatible debuggers
Microsoft Visual Studio VC Package 1.0
Microsoft Visual Studio VC Package
Mono Debugging for Visual Studio Mono.Debugging.VisualStudio
Support for debugging Mono processes with Visual Studio.
NuGet Package Manager 4.0.0
NuGet Package Manager in Visual Studio. For more information about NuGet, visit http://docs.nuget.org/.
SQL Server Data Tools 15.1.61124.0
Microsoft SQL Server Data Tools
TSCPackage Extension 1.0
TSCPackage Visual Studio Extension Detailed Info
TypeScript tools for Visual Studio
Visual C++ for Linux Development 1.0.6
Visual C++ for Linux Development
Visual Studio tools for CMake 1.0
Visual Studio tools for CMake
Visual Studio Tools for Universal Windows Apps 15.0.26009.00
The Visual Studio Tools for Universal Windows apps allow you to build a single universal app experience that can reach every device running Windows 10: phone, tablet, PC, and more. It includes the Microsoft Windows 10 Software Development Kit.
Xamarin 126.96.36.1999 (7c3dcf2)
Visual Studio extension to enable development for Xamarin.iOS and Xamarin.Android.
Xamarin.Android 188.8.131.52 (72366f7)
Visual Studio extension to enable development for Xamarin.Android.
Xamarin.iOS 10.4.0.33 (d93ae7e)
Visual Studio extension to enable development for Xamarin.iOS.
The mdb for the Android runtime is almost 8mb, so I'm thinking that size alone is not an issue. OTOH, you can't really set a breakpoint on that code. Based on the OutOfMemory I'm inclined to think of some kind of recursiveness not working properly. I'm not being able to repro, though. Can you share a brief snippet of the code you're trying to set a breakpoint too? That may give me a proper clue on what's happening.
The other (better) option is a memory dump of the process at that point, so we can pinpoint exactly where the memory is being consumed.
Also, just in case you know, is this working in VS2015?
As we didn't get more information to keep investigating the issue and there were several improvements since the bug was reported, I'm resolving the bug.
If you do still face this issue and think it needs more investigation, please add the requested information and reopen it including updated environment information.
I tried reproducing this issue since then, but could not with latest stable releases. Thanks!