PoC for ARM64 support of LocalDB

[Matteo-T]

@DavoudEshtehari / @cheenamalhotra / @David-Engel - FYI, this the "Proof of Concept" I've been toying with in the last couple of days.

The logic is as follows:

• Try to existing logic, which is to load the SqlLocalDB DLL
• If that fails (typically because there is an architecture mismatch, like running the driver under ARM64 and trying to load SqlUserInstance.dll that is AMD64):
  • lookup the registry and get the latest SqlLocalDb.exe installer on the machine
  • spawn SqlLocalDB.exe s <instancename> (to make sure the instance is started) - it's a no-op if it is already running, I believe
  • spawn SqlLocalDB.exe i <instancename> to get the connection string, i.e. the named pipe to use - assumption: SqlLocalDB always exposed named pipes
  • use that connection string

Here's my test app (built for net7.0):

using System.Diagnostics;
using System.Runtime.InteropServices;
using Microsoft.Data.SqlClient;
class Program
{
    // Requires SqlLocalDB installed on the machine
    // Ideally on ARM64
    // 
    static string connectionString = @"Data Source=(localdb)\MSSQLLocalDB;Initial Catalog=master;Integrated Security=true";

    static void Main(string[] args)
    {
        bool UseManagedNetworkingOnWindows = args.Length == 0;

        AppContext.SetSwitch("Switch.Microsoft.Data.SqlClient.UseManagedNetworkingOnWindows", UseManagedNetworkingOnWindows);

        Console.WriteLine("Run");
        Console.WriteLine($" dotnet-trace collect --providers \"Microsoft.Data.SqlClient.EventSource\" --process-id {Process.GetCurrentProcess().Id}");
        Console.WriteLine("then press <ENTER>");
        Console.ReadLine();

        Console.WriteLine($"UseManagedNetworkingOnWindows={UseManagedNetworkingOnWindows}");
        Console.WriteLine($"Environment.Is64BitOperatingSystem={Environment.Is64BitOperatingSystem}");
        Console.WriteLine($"Environment.Is64BitProcess={Environment.Is64BitProcess}");
        Console.WriteLine($"GetSystemVersion()={RuntimeEnvironment.GetSystemVersion()}");
        Console.WriteLine($"Environment.OSVersion.VersionString={Environment.OSVersion.VersionString}");
        Console.WriteLine($"RuntimeInformation.OSArchitecture={RuntimeInformation.OSArchitecture}");
        Console.WriteLine($"RuntimeInformation.RuntimeIdentifier={RuntimeInformation.RuntimeIdentifier}");
        Console.WriteLine($"RuntimeInformation.ProcessArchitecture={RuntimeInformation.ProcessArchitecture}");
        Console.WriteLine();

        var query = "SELECT @@VERSION, @@SERVERNAME";

        Console.WriteLine($"Connection string: {connectionString}");
        Console.WriteLine($"Query: {query}");

        using (SqlConnection connection = new SqlConnection(connectionString))
        {
            connection.Open();
            var cmd = new SqlCommand(@"SELECT @@VERSION, @@SERVERNAME", connection);
            using (var reader = cmd.ExecuteReader())
            {
                while (reader.Read())
                {
                    Console.WriteLine(reader.GetString(0));
                    Console.WriteLine(reader.GetString(1));
                }
            }
        }
    }
}

It's output looks like this on my ARM64 box:

Run
 dotnet-trace collect --providers "Microsoft.Data.SqlClient.EventSource" --process-id 21568
then press <ENTER>

UseManagedNetworkingOnWindows=True
Environment.Is64BitOperatingSystem=True
Environment.Is64BitProcess=True
GetSystemVersion()=v4.0.30319
Environment.OSVersion.VersionString=Microsoft Windows NT 10.0.22621.0
RuntimeInformation.OSArchitecture=Arm64
RuntimeInformation.RuntimeIdentifier=win10-arm64
RuntimeInformation.ProcessArchitecture=Arm64

Connection string: Data Source=(localdb)\MSSQLLocalDB;Initial Catalog=master;Integrated Security=true
Query: SELECT @@VERSION, @@SERVERNAME
Microsoft SQL Server 2022 (RTM-CU1) (KB5022375) - 16.0.4003.1 (X64)
        Jan 27 2023 16:51:31
        Copyright (C) 2022 Microsoft Corporation
        Express Edition (64-bit) on Windows 10 Enterprise 10.0 <X64> (Build 22621: ) (VM)

SQLToolsArm-2\LOCALDB#5E67B8B5

[Matteo-T]

This was not meant to be part of the change. I may have been playing around with it on my AMD64 dev box, so I wanted to make it fail artificially. Oops...

[Matteo-T]

Any takers? Good? Bad? Horrible? :)

[ErikEJ]

Add a timeout

[Matteo-T]

Yup - keep in mind this is very crude PoC.

[ErikEJ]

Yes, LocalDB only uses named pipes (no networking)

[ErikEJ]

var match

[Matteo-T]

Definitely!

[JRahnama]

Closing as this is a POC and work has been carried forward in a different PR.