Is there a way to improve the performance of the ORM mapper of Linq2Db using the FirebirdDataProvider. I retrieve 1831 records from a table having 39 columns (all INTEGER, DECIMAL(13,5) and 2x VARCHAR(100)). The longest varchar is 37 chars. Approximately 60% of all the values are null. I tried to log what takes so much time:

var sw = new System.Diagnostics.Stopwatch();
this.db.OnTraceConnection = (traceInfo) =>
{
    switch (traceInfo.TraceInfoStep)
    {
        case TraceInfoStep.BeforeExecute:
            sw.Start();
            break;
        case TraceInfoStep.AfterExecute:
            Console.WriteLine($"DB Request Time: {sw.ElapsedMilliseconds} ms");
            sw.Restart();
            break;
        case TraceInfoStep.Completed:
            Console.WriteLine($"Mapping Time: {sw.ElapsedMilliseconds} ms");
            break;
    }
};

Here is the result:

DB Request Time: 49 ms
Mapping Time: 1805 ms

DB Request Time: 43 ms
Mapping Time: 1870 ms

DB Request Time: 47 ms
Mapping Time: 1653 ms

DB Request Time: 40 ms
Mapping Time: 1820 ms

PC Specs:

i7-13700K
64GB 4000MHz

Network should also not be the bottleneck. The last check I did resulted in 898.4 Mbit/s

I tried to use compiled queries but this did not improve the query at all:

DB Request Time: 45 ms
Mapping Time: 1953 ms

DB Request Time: 47 ms
Mapping Time: 1804 ms

DB Request Time: 48 ms
Mapping Time: 1832 ms

DB Request Time: 41 ms
Mapping Time: 1881 ms