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Hey guys hopefully the title wasn't too bad, hard to describe succinctly.

So I have an ASP.net core 2.0 server running (via Kestrel) on a VPS hosted in Australia (I'm in New Zealand, ~50ms latency to server). An HTTP Get action causes the following code on the ASP.net server to run, where I query an SQL server (also running on the vps) and return the result:

public async Task<string> GetTopContactPhoto(int contactUID)
    {
        // Open connection if not already open
        if (conn.State != System.Data.ConnectionState.Open) { conn.Open(); }

        // Get number of rows
        string sqlRequest = string.Format("select top 1 imageData from IMAGES where contactUID=@contactID;");

        // Return value
        using (SqlCommand cmd = new SqlCommand(sqlRequest, conn))
        {
            cmd.Parameters.AddWithValue("@contactID", contactUID);
            return Convert.ToBase64String((byte[])await cmd.ExecuteScalarAsync());
        }
    }

Now this whole process takes pretty consistently ~5-6 seconds from the time the HTTP Get request is made, to the time the result is given, image sizes ~2MB.

But here's the thing, when I compile and run the ASP.Net core server on my development PC, on a separate continent altogether to the VPS (still running the SQL server), the whole process takes only ~2 seconds, less if I resize the image before responding to Get request.

Any ideas what could be going wrong? This problem has vexed me for months, with no amount of googling doing the trick.

Matthew Minish
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  • Have you worked out exactly where the time is being taken? e.g. db access or web server? I doubt googling is going to solve this. You will need to profile your application and db in both environments and work out the difference. – SpruceMoose Apr 10 '18 at 08:13
  • The time seems to be spent on the return statement, having timed everything else it comes to ~2 seconds, but from the time return is hit to the time the data is received, about 4 seconds is unaccounted for – Matthew Minish Apr 11 '18 at 07:31
  • Just to confirm, are you connecting to the same SQL Server instance in both cases/environments? – SpruceMoose Apr 11 '18 at 08:05
  • Yes I am indeed – Matthew Minish Apr 11 '18 at 09:07

0 Answers0