Skip to main content

Experimental: Reducing the size of .NET Core applications with Mono's Linker

The .NET team has built a linker to reduce the size of .NET Core applications. It is built on top of the excellent and battle-tested mono linker. The Xamarin tools also use this linker so it makes sense to try it out and perhaps use it everywhere!

"In trivial cases, the linker can reduce the size of applications by 50%. The size wins may be more favorable or more moderate for larger applications. The linker removes code in your application and dependent libraries that are not reached by any code paths. It is effectively an application-specific dead code analysis." - Using the .NET IL Linker

I recently updated a 15 year old .NET 1.1 application to cross-platform .NET Core 2.0 so I thought I'd try this experimental linker on it and see the results.

The linker is a tool one can use to only ship the minimal possible IL code and metadata that a set of programs might require to run as opposed to the full libraries. It is used by the various Xamarin products to extract only the bits of code that are needed to run an application on Android, iOS and other platforms.

I'll add this line to a nuget.config in my project's folder. Note that NuGet will inherit global settings and ADD this line.

<?xml version="1.0" encoding="utf-8"?>

<configuration>

 <packageSources>

    <add key="dotnet-core" value="https://dotnet.myget.org/F/dotnet-core/api/v3/index.json" />

 </packageSources>

</configuration>

Then I'll add the IL Linker's NuGet package to my project with this command line command (or from Visual Studio):

dotnet add package ILLink.Tasks -v 0.1.4-preview-906439

The assemblies will automatically be "trimmed" when they are published (not built) so I'll build it twice, disabling it with a switch:

D:\github\TinyOS\OS Project>dotnet publish -c release -r win-x64 -o notlinked /p:LinkDuringPublish=false

Microsoft (R) Build Engine version 15.3 for .NET Core


  TinyOSCore -> D:\github\TinyOS\OS Project\bin\Release\netcoreapp2.0\win-x64\TinyOSCore.dll

  TinyOSCore -> D:\github\TinyOS\OS Project\notlinked\


D:\github\TinyOS\OS Project>dotnet publish -c release -r win-x64 -o linked

Microsoft (R) Build Engine version 15.3 for .NET Core


  TinyOSCore -> D:\github\TinyOS\OS Project\bin\Release\netcoreapp2.0\win-x64\TinyOSCore.dll

  TinyOSCore -> D:\github\TinyOS\OS Project\linked\

And here's the results:

image

You can also run it with  /p:ShowLinkerSizeComparison=true and get a nice table. I've trimmed the table as it's super long.

  TinyOSCore -> D:\github\TinyOS\OS Project\bin\Release\netcoreapp2.0\win-x64\TinyOSCore.dll

                                                             Before linking (B)   After linking (B)    Size decrease

-----------                                                  -----------          -----------          -----------

Total size of assemblies                                     48,025,824           16,740,056           65.14%    

-----------                                                  -----------          -----------          -----------

TinyOSCore.dll                                               36,352               36,352               0.00%     

Microsoft.Extensions.Configuration.dll                       24,584               24,584               0.00%     

Microsoft.Extensions.Configuration.Abstractions.dll          20,480               20,480               0.00%     

Microsoft.Extensions.Configuration.Binder.dll                24,064               24,064               0.00%     

Microsoft.Extensions.Configuration.FileExtensions.dll        22,528               22,528               0.00%     

Microsoft.Extensions.Configuration.Json.dll                  24,072               24,072               0.00%     

Microsoft.Extensions.DependencyInjection.dll                 46,600               46,600               0.00%     

Microsoft.Extensions.DependencyInjection.Abstractions.dll    35,336               35,336               0.00%     

Microsoft.Extensions.FileProviders.Abstractions.dll          17,920               17,920               0.00%     

Microsoft.Extensions.FileProviders.Physical.dll              31,240               31,240               0.00%     

Microsoft.Extensions.FileSystemGlobbing.dll                  39,432               39,432               0.00%     

Microsoft.Extensions.Options.dll                             26,120               26,120               0.00%     

Microsoft.Extensions.Options.ConfigurationExtensions.dll     16,904               16,904               0.00%     

Microsoft.Extensions.Primitives.dll                          33,800               33,800               0.00%     

Newtonsoft.Json.dll                                          639,488              639,488              0.00%     

Microsoft.CSharp.dll                                         1,092,096            392,192              64.09%    

Microsoft.VisualBasic.dll                                    465,416              0                    100.00%   

Microsoft.Win32.Primitives.dll                               18,968               4,608                75.71%    

Microsoft.Win32.Registry.dll                                 85,008               0                    100.00%   

SOS.NETCore.dll                                              54,264               0                    100.00%   

System.AppContext.dll                                        14,336               2,560                82.14%    

System.Buffers.dll                                           14,336               2,560                82.14%    

System.Collections.Concurrent.dll                            206,360              31,744               84.62%    

System.Collections.Immutable.dll                             2,378,264            0                    100.00%   

System.Collections.NonGeneric.dll                            96,792               24,576               74.61%    

System.Collections.Specialized.dll                           88,608               15,360               82.67%    

System.Collections.dll                                       326,664              52,224               84.01%    


  TinyOSCore -> D:\github\TinyOS\OS Project\bin\Release\netcoreapp2.0\win-x64\publish\

You can see in some places where there's no size decrease. That's because I'm using those assemblies completely. Some see a 100% decrease - they've been removed entirely - because I'm not using the Registry, for example. And some see a fractional decrease because I'm using some methods but not others.

You can check out the full instructions and try this yourself at https://github.com/dotnet/core/blob/master/samples/linker-instructions.md. Again, it's a work in progress.

Sponsor: Check out JetBrains Rider: a new cross-platform .NET IDE. Edit, refactor, test and debug ASP.NET, .NET Framework, .NET Core, Xamarin or Unity applications. Learn more and download a 30-day trial!


© 2017 Scott Hanselman. All rights reserved.
     


from Scott Hanselman's Blog http://feeds.hanselman.com/~/452296766/0/scotthanselman~Experimental-Reducing-the-size-of-NET-Core-applications-with-Monos-Linker.aspx
Labels:

Comments

Post a Comment

Popular posts from this blog

dotnet sdk list and dotnet sdk latest

Can someone make .NET Core better with a simple global command? Fanie Reynders did and he did it in a simple and elegant way. I'm envious, in fact, because I spec'ed this exact thing out in a meeting a few months ago but I could have just done it like he did and I would have used fewer keystrokes! Last year when .NET Core was just getting started, there was a "DNVM" helper command that you could use to simplify dealing with multiple versions of the .NET SDK on one machine. Later, rather than 'switching global SDK versions,' switching was simplified to be handled on a folder by folder basis. That meant that if you had a project in a folder with no global.json that pinned the SDK version, your project would use the latest installed version. If you liked, you could create a global.json file and pin your project's folder to a specific version. Great, but I would constantly have to google to remember the format for the global.json file, and I'd constan...
Post a Comment
Read more

15 Web Design Trends to Watch in 2018

The modern world is full of extraordinary things that influence our imagination and mood. Our soul needs a perfect atmosphere and impressive spots. To apply such things in practice, we have submitted the list of the web trends that deserve your attention. Robert frost design analysis will meet all your wishes and expectations. Image Source Web Design Trends to Watch in 2018 1. More Organic Shapes Until this year, web design, as well as mobile design, were based on the right-angled and sharp-edged shapes. However, it seems that this year will bring some significant changes in the field of web design. The recent trends will offer the absolute rounded corners. In addition, the web design of 2018 will make the real things look like the cartoonish ones. 2.   Bold Minimalism Although some of you may think that this web design trend will not attract the Internet users. Indeed, the notion of minimalism is often associated with boredom and dullness. However, in this case, bold ...
Post a Comment
Read more

R vs Python for Machine Learning

There are so many things to learn before to choose which language is good for Machine Learning. We will discuss each and everything about R as well as Python and the situation or problem in which situation we have to use which language. Let’s start Python and R are the two most Commonly used Programming Languages for Machine Learning and because of the popularity of both the languages Novice or you can say fresher are getting confused, whether they should choose R or Python language to commence their career in the Machine learning domain. Don’t worry guys through this article we will discuss R vs Python for Machine Learning. So, without exaggerating this article let’s get started. We will start it from the very Basics things or definitions. R vs Python for Machine Learning Introduction R is a programming language made by statisticians and data miners for statistical analysis and graphics supported by R foundation for statistical computing. R also provides high-quality graphics and...
1 comment
Read more