.NET Core SqlConnection ConnectRetryCount not work?

[OdaShinsuke]

.NET Core SqlConnection ConnectRetryCount not work?

SqlConnection ConnectRetryCount behaves differently between .NET Framework and .NET Core.

To reproduce

static string connstr = @"Data Source=localhost;Initial Catalog=master;Integrated Security=True;Connect Timeout=5;Encrypt=False;";

static void Main(string[] args)
{
    Test_ConnectRetry();
    Console.ReadKey();
}
static void Test_ConnectRetry()
{
    Stopwatch s = null;
    try
    {
        using (var conn = new SqlConnection(connstr + "ConnectRetryCount=5;ConnectRetryInterval=5;"))
        using (var cmd = new SqlCommand(@"select 1", conn))
        {
            conn.Open();

            Console.WriteLine(cmd.ExecuteScalar());
            Console.WriteLine("net stop <sql server service>");
            Console.ReadKey(); // manually SQL Server service stop
            Console.WriteLine("SQL Server Service stoped!");
            s = Stopwatch.StartNew();

            cmd.ExecuteScalar();

            Console.WriteLine("not run");
        }
    }
    catch (Exception ex)
    {
        s.Stop();
        Console.WriteLine(ex.Message);
        // .NET Framwork is over 30000ms, .NET Core is about 7000ms
        Console.WriteLine(s.ElapsedMilliseconds);
    }
}

• ElapsedMilliseconds
  • .NET Framework 4.7.2 + SqlClient 4.7.0
    • over 30000 milliseconds
  • .NET Core 3.0 + SqlClient 4.7.0
    • about 7000 milliseconds

Expected behavior

Changed ConnectRetryCount value in .NET Core

• ConnectRetryCount=0
  • thrown exception immediately
• ConnectRetryCount=1
  • thrown exception after about 7000 milliseconds
• ConnectRetryCount=5
  • thrown exception after about 7000 milliseconds

ConnectRetryCount not work?

[ErikEJ]

Have you tried Microsoft.Data.SqlClient?

[OdaShinsuke]

I tried Microsoft.Data.SqlClient.

• 1.1.0-preview1.19275.1
• 1.0.19269.1

execution results of both versions were as follows.

• ConnectRetryCount=0
  • thrown exception immediately
• ConnectRetryCount=1
  • thrown exception after about 14000 milliseconds
• ConnectRetryCount=5
  • thrown exception after about 14000 milliseconds

almost same result ConnectRetryCount=1 and 5.

[cheenamalhotra]

@OdaShinsuke

Thanks for reporting the issue. The behavior should be same as far as I can tell from implementation goals. We'll update you when we investigate the root cause.

[cheenamalhotra]

Hi @OdaShinsuke

We recently fixed a bug in Connection Resiliency (#304) that was broken in one of the 4.7.0-preview versions of System.Data.SqlClient and eventually landed in Microsoft.Data.SqlClient.

PR #310 contains the fix for this issue that has been merged, would you like to give it try to check if this is the same problem?

A NuGet package containing this fix can be found here: v1.1.0-build.19320.1-d0672d2

[OdaShinsuke]

Hi @cheenamalhotra

I tried v1.1.0-build.19320.1-d0672d2. and this problem improved.
Thanks.