在 ubuntu 上构建 dotnet core 3.0 依赖项时资源暂时不可用

Question

我有一个 .net core 3.0 项目，我正在尝试对其进行 dockerise。调用的项目文件SuperSecretProject.csproj如下：

<?xml version="1.0" encoding="utf-8"?>
<Project Sdk="Microsoft.NET.Sdk.Web">
  <PropertyGroup>
    <TargetFramework>netcoreapp3.0</TargetFramework>
    <StartupObject>SuperSecretProject.Program</StartupObject>
    <UserSecretsId>cee96675-39d5-486b-bcca-9db409d1d0c4</UserSecretsId>
    <DockerDefaultTargetOS>Linux</DockerDefaultTargetOS>
    <DockerfileContext>.</DockerfileContext>
  </PropertyGroup>
  <ItemGroup>
    <PackageReference Include="Microsoft.EntityFrameworkCore.Tools" Version="3.0.0">
      <PrivateAssets>all</PrivateAssets>
      <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
    </PackageReference>
    <PackageReference Include="Microsoft.Extensions.Http.Polly" Version="3.0.1" />
    <PackageReference Include="Microsoft.Extensions.Logging.Debug" Version="3.0.0" />
    <PackageReference Include="Microsoft.VisualStudio.Azure.Containers.Tools.Targets" Version="1.9.5" />
    <PackageReference Include="Microsoft.VisualStudio.Web.CodeGeneration.Design" Version="3.0.0" />
    <PackageReference Include="Newtonsoft.Json" Version="12.0.3" />
    <PackageReference Include="Npgsql.EntityFrameworkCore.PostgreSQL" Version="3.1.0" />
  </ItemGroup>
</Project>

泊坞窗文件是：

FROM mcr.microsoft.com/dotnet/core/sdk:3.1 AS debug

WORKDIR /build-debug
COPY ./SuperSecretProject.csproj ./
RUN dotnet restore

ENTRYPOINT ["echo", "hello"] 

但是，在构建时，我得到了Resource temporarily unavailable.Eg docker build -f ./docker/Dockerfile . -t test：

Step 4/5 : RUN dotnet restore
 ---> Running in d4ca119fa22c
  Retrying 'FindPackagesByIdAsync' for source 'https://api.nuget.org/v3-flatcontainer/microsoft.extensions.logging.abstractions/index.json'.
  Resource temporarily unavailable
  Retrying 'FindPackagesByIdAsync' for source 'https://api.nuget.org/v3-flatcontainer/system.threading.tasks.extensions/index.json'.
  Resource temporarily unavailable
....

一些研究表明 docker 对它可以运行的任务数量有限制：https : //success.docker.com/article/how-to-reserve-resource-temporously-unavailable-errors-due-to-tasksmax -setting 但是这个修复似乎不起作用。

注意：如果将第 4 步更改为，我可以成功构建 docker 映像，dotnet restore --disable-parallel但是对于更大的项目，构建时间变得太长。如果所有async任务dotnet restore都可以并行完成就好了。

Answer 1

重新启动 docker 守护进程会有所帮助。

供参考： https://forums.docker.com/t/dotnet-restore-fails-when-building-in-docker-container/95386