Skip to main content
Redhat Developers  Logo
  • Products

    Featured

    • Red Hat Enterprise Linux
      Red Hat Enterprise Linux Icon
    • Red Hat OpenShift AI
      Red Hat OpenShift AI
    • Red Hat Enterprise Linux AI
      Linux icon inside of a brain
    • Image mode for Red Hat Enterprise Linux
      RHEL image mode
    • Red Hat OpenShift
      Openshift icon
    • Red Hat Ansible Automation Platform
      Ansible icon
    • Red Hat Developer Hub
      Developer Hub
    • View All Red Hat Products
    • Linux

      • Red Hat Enterprise Linux
      • Image mode for Red Hat Enterprise Linux
      • Red Hat Universal Base Images (UBI)
    • Java runtimes & frameworks

      • JBoss Enterprise Application Platform
      • Red Hat build of OpenJDK
    • Kubernetes

      • Red Hat OpenShift
      • Microsoft Azure Red Hat OpenShift
      • Red Hat OpenShift Virtualization
      • Red Hat OpenShift Lightspeed
    • Integration & App Connectivity

      • Red Hat Build of Apache Camel
      • Red Hat Service Interconnect
      • Red Hat Connectivity Link
    • AI/ML

      • Red Hat OpenShift AI
      • Red Hat Enterprise Linux AI
    • Automation

      • Red Hat Ansible Automation Platform
      • Red Hat Ansible Lightspeed
    • Developer tools

      • Red Hat Trusted Software Supply Chain
      • Podman Desktop
      • Red Hat OpenShift Dev Spaces
    • Developer Sandbox

      Developer Sandbox
      Try Red Hat products and technologies without setup or configuration fees for 30 days with this shared Openshift and Kubernetes cluster.
    • Try at no cost
  • Technologies

    Featured

    • AI/ML
      AI/ML Icon
    • Linux
      Linux Icon
    • Kubernetes
      Cloud icon
    • Automation
      Automation Icon showing arrows moving in a circle around a gear
    • View All Technologies
    • Programming Languages & Frameworks

      • Java
      • Python
      • JavaScript
    • System Design & Architecture

      • Red Hat architecture and design patterns
      • Microservices
      • Event-Driven Architecture
      • Databases
    • Developer Productivity

      • Developer productivity
      • Developer Tools
      • GitOps
    • Secure Development & Architectures

      • Security
      • Secure coding
    • Platform Engineering

      • DevOps
      • DevSecOps
      • Ansible automation for applications and services
    • Automated Data Processing

      • AI/ML
      • Data Science
      • Apache Kafka on Kubernetes
      • View All Technologies
    • Start exploring in the Developer Sandbox for free

      sandbox graphic
      Try Red Hat's products and technologies without setup or configuration.
    • Try at no cost
  • Learn

    Featured

    • Kubernetes & Cloud Native
      Openshift icon
    • Linux
      Rhel icon
    • Automation
      Ansible cloud icon
    • Java
      Java icon
    • AI/ML
      AI/ML Icon
    • View All Learning Resources

    E-Books

    • GitOps Cookbook
    • Podman in Action
    • Kubernetes Operators
    • The Path to GitOps
    • View All E-books

    Cheat Sheets

    • Linux Commands
    • Bash Commands
    • Git
    • systemd Commands
    • View All Cheat Sheets

    Documentation

    • API Catalog
    • Product Documentation
    • Legacy Documentation
    • Red Hat Learning

      Learning image
      Boost your technical skills to expert-level with the help of interactive lessons offered by various Red Hat Learning programs.
    • Explore Red Hat Learning
  • Developer Sandbox

    Developer Sandbox

    • Access Red Hat’s products and technologies without setup or configuration, and start developing quicker than ever before with our new, no-cost sandbox environments.
    • Explore Developer Sandbox

    Featured Developer Sandbox activities

    • Get started with your Developer Sandbox
    • OpenShift virtualization and application modernization using the Developer Sandbox
    • Explore all Developer Sandbox activities

    Ready to start developing apps?

    • Try at no cost
  • Blog
  • Events
  • Videos

Improving ASP.NET Core build speed on Red Hat OpenShift

 

July 10, 2019
Tom Deseyn
Related topics:
.NETKubernetes
Related products:
Red Hat OpenShift

Share:

    In previous articles, I’ve covered two strategies for improving .NET Core build speed on Red Hat OpenShift by reducing time to restore dependencies: adding a local NuGet server and using incremental builds. In this article, I’ll look at another strategy: using a custom base image that has includes the dependencies.

    ASP.NET Core

    ASP.NET Core is the de facto framework for building web applications with .NET Core. The framework is open source on GitHub; however, for 1.x and 2.x, it does not have the infrastructure needed for a third party (e.g., Red Hat) to build it from source so that it matches Microsoft releases.

    Building from source is a key feature for open source projects. It reduces vendor lock-in by enabling other companies and communities to build and support the software. The ability to build code from source is a requirement for including packages in the default package repositories of Linux distributions (like Fedora, Debian, and Ubuntu). The upcoming ASP.NET Core 3.0 will be buildable from source!

    Because ASP.NET Core 2.x cannot be built from source, it cannot be included in Red Hat Enterprise Linux packages and Red Hat OpenShift’s .NET Core builder (s2i-dotnetcore). This leads to long restore times because applications need to fetch and extract those packages from nuget.org (or a local NuGet server).

    aspnet image streams

    As a Red Hat OpenShift user, to work around this limitation, you can build a custom image that includes the ASP.NET Core NuGet packages. I’ve written a resource file that does exactly that. You can import it into OpenShift using:

    $ oc create -f https://raw.githubusercontent.com/redhat-developer/s2i-dotnetcore/master/templates/aspnet-2.x.json
    

    If you have a look into the file, you’ll see it defines an aspnet:2.1 and aspnet:2.2 image stream that builds on top of s2i-dotnetcore’s dotnet:2.1 and dotnet:2.2 using a Docker strategy. The ASP.NET Core packages are added by performing a dotnet new web. Because we build on top of the dotnet image streams, the aspnet streams will automatically be rebuilt when the base images are updated with security patches.

    After importing the file, it takes a couple of minutes for the images to be built.

    Let’s compare the difference in build speed by building https://github.com/redhat-developer/s2i-dotnetcore-ex using dotnet:2.2 and aspnet:2.2.

    $ oc new-app --name=dotnetapp dotnet:2.2~https://github.com/redhat-developer/s2i-dotnetcore-ex#dotnetcore-2.2 --build-env DOTNET_STARTUP_PROJECT=app
    $ oc new-app --name=aspnetapp aspnet:2.2~https://github.com/redhat-developer/s2i-dotnetcore-ex#dotnetcore-2.2 --build-env DOTNET_STARTUP_PROJECT=app
    

    When we do five builds, we get these build times:

    base image min max avg
    dotnet:2.1 43s 1m30s 47s
    aspnet:2.1 23s 31s 24s

    As you can see, the build times are halved using the aspnet image. What’s more, the build time variance is much smaller.

    Conclusion

    We can significantly reduce build times for .NET Core applications by creating a custom build image that includes common dependencies. aspnet-2.x.json provides build configurations that add ASP.NET 2.x Core packages to the s2i-dotnetcore dotnet images.

    Last updated: March 28, 2023

    Recent Posts

    • Meet the Red Hat Node.js team at PowerUP 2025

    • How to use pipelines for AI/ML automation at the edge

    • What's new in network observability 1.8

    • LLM Compressor: Optimize LLMs for low-latency deployments

    • How to set up NVIDIA NIM on Red Hat OpenShift AI

    What’s up next?

     

    Red Hat Developers logo LinkedIn YouTube Twitter Facebook

    Products

    • Red Hat Enterprise Linux
    • Red Hat OpenShift
    • Red Hat Ansible Automation Platform

    Build

    • Developer Sandbox
    • Developer Tools
    • Interactive Tutorials
    • API Catalog

    Quicklinks

    • Learning Resources
    • E-books
    • Cheat Sheets
    • Blog
    • Events
    • Newsletter

    Communicate

    • About us
    • Contact sales
    • Find a partner
    • Report a website issue
    • Site Status Dashboard
    • Report a security problem

    RED HAT DEVELOPER

    Build here. Go anywhere.

    We serve the builders. The problem solvers who create careers with code.

    Join us if you’re a developer, software engineer, web designer, front-end designer, UX designer, computer scientist, architect, tester, product manager, project manager or team lead.

    Sign me up

    Red Hat legal and privacy links

    • About Red Hat
    • Jobs
    • Events
    • Locations
    • Contact Red Hat
    • Red Hat Blog
    • Inclusion at Red Hat
    • Cool Stuff Store
    • Red Hat Summit

    Red Hat legal and privacy links

    • Privacy statement
    • Terms of use
    • All policies and guidelines
    • Digital accessibility

    Report a website issue