macOS prerequisites: open files limit in 2.0.2+

[dasMulli]

The macOS prerequisites doc has a section "Increase the maximum open file limit" detailing how to set a system-wide higher open file limit for processes using launchd/launchctl or ulimit.

Since dotnet/coreclr#14054 has been merged and will be part of the 2.0.2 release, this should no longer be necessary as this appears to have been a bug in CoreCLR trying to set a higher limit itself, but with a wrong value. The value should now be set automatically to the system's highest allowed value (~10500 IIRC) and no manual intervention is needed.

cc @mairaw

[mairaw]

Thanks @dasMulli.

@leecow @janvorli this issue is for the following topic:
https://docs.microsoft.com/en-us/dotnet/core/macos-prerequisites?tabs=netcore2x#increase-the-maximum-open-file-limit

When we release .NET Core 2.0.2, should we keep that info but note that is only applicable to older versions?

[leecow]

A note indicating the setting is more likely to be needed in older versions of Core sounds like the right edit.

[janvorli]

Yes, the setting is only applicable in older versions, in the 2.0.2, it doesn't make sense, we already set it to the max possible value in the PAL.

[mairaw]

Ok thanks for the feedback @leecow @janvorli!

[chrisckc]

Hi, i downloaded and installed dotnet-sdk-2.0.3-osx-gs-x64.pkg yesterday and had to increase the open file limit to much more than 2048 to get the dotnet command to work properly.

Initially set the open file limit to 2048 as suggested in the current documentation (using the suggested method) before i even tried the dotnet cli, but i found that i was unable to run "dotnet --version" , "dotnet new" or "dotnet restore" without getting seemingly random errors regarding not being able to load various assemblies etc. Due to the errors not being consistent it made me suspect the open file limit could still be an issue.

Here are some examples of the errors to help anyone searching to find this post:

$ dotnet new

Getting ready...
Error: Could not install "/usr/local/share/dotnet/sdk/2.0.3/Templates/microsoft.dotnet.web.itemtemplates.2.0.3.nupkg".
Error: Error getting value from 'TemplateInfo' on 'Microsoft.TemplateEngine.Edge.Settings.TemplateCache'.
Error: Could not install "/usr/local/share/dotnet/sdk/2.0.3/Templates/microsoft.dotnet.common.projecttemplates.2.0.1.0.0-beta2-20170810-304.nupkg".
Error: Error getting value from 'TemplateInfo' on 'Microsoft.TemplateEngine.Edge.Settings.TemplateCache'.
Error: Could not install "/usr/local/share/dotnet/sdk/2.0.3/Templates/microsoft.dotnet.web.spa.projecttemplates.2.0.3.nupkg".
Error: Error getting value from 'TemplateInfo' on 'Microsoft.TemplateEngine.Edge.Settings.TemplateCache'.
Error: Could not install "/usr/local/share/dotnet/sdk/2.0.3/Templates/microsoft.dotnet.web.projecttemplates.2.0.2.0.3.nupkg".
Error: Error getting value from 'TemplateInfo' on 'Microsoft.TemplateEngine.Edge.Settings.TemplateCache'.
Error: Could not install "/usr/local/share/dotnet/sdk/2.0.3/Templates/microsoft.dotnet.common.itemtemplates.1.0.0-beta2-20170810-304.nupkg".
Error: Error getting value from 'TemplateInfo' on 'Microsoft.TemplateEngine.Edge.Settings.TemplateCache'.
Error: Could not install "/usr/local/share/dotnet/sdk/2.0.3/Templates/microsoft.dotnet.test.projecttemplates.2.0.1.0.0-beta2-20170810-304.nupkg".
Error: Error getting value from 'TemplateInfo' on 'Microsoft.TemplateEngine.Edge.Settings.TemplateCache'.
Error getting value from 'TemplateInfo' on 'Microsoft.TemplateEngine.Edge.Settings.TemplateCache'.
Could not load file or assembly 'System.Reflection.Emit.Lightweight, Version=4.0.3.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a'. A device attached to the system is not functioning.
(Exception from HRESULT: 0x8007001F)
at System.Linq.Expressions.Compiler.LambdaCompiler..ctor(AnalyzedTree tree, LambdaExpression lambda)

$ dotnet --version

Unhandled Exception: System.TypeInitializationException: The type initializer for 'Microsoft.DotNet.Cli.Utils.Reporter' threw an exception. ---> System.IO.FileLoadException: Could not load file or assembly 'System.IO, Version=4.1.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a'. A device attached to the system is not functioning.
(Exception from HRESULT: 0x8007001F)
at Microsoft.DotNet.Cli.Utils.Reporter.Reset()

$ dotnet new webapi

The template "ASP.NET Core Web API" was created successfully.
This template contains technologies from parties other than Microsoft, see https://aka.ms/template-3pn for details.

Processing post-creation actions...
Running 'dotnet restore' on /Users/username/Documents/Development/DotNetProjects/dotnetcore2-test/dotnetcore2-test.csproj...

Unhandled Exception: System.TypeInitializationException: The type initializer for 'Microsoft.DotNet.Cli.Utils.Reporter' threw an exception. ---> System.IO.FileLoadException: Could not load file or assembly 'System.Console, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a'. A device attached to the system is not functioning.
(Exception from HRESULT: 0x8007001F)
at Microsoft.DotNet.Cli.Utils.Reporter.Reset()

After trying many commands, this was the only command which actually showed a meaningful error message:

$ dotnet new -l

System.IO.IOException: Too many open files in system

After setting my max open files to 524288, the problem was solved. I didnt want to start messing about gradually increasing it.
I also set max proc to 2048 while i was at it for good measure.

You can check the current settings on macOS using:
$ launchctl limit

I am definitely running dotnet 2.0.3, here is the output of "dotnet --version" now that its working:

$ dotnet --version

2.0.3

I am running macOS High Sierra 10.13.1 with 16GB RAM

If this is still an issue the documentation needs to be updated to reflect the higher limit that is required.