public wait_stats Subtract(wait_stats instance)
{
double ticksDelta = ticks - instance.ticks;
var ticksDeltaFactor = Stopwatch.Frequency / ticksDelta;
var result = new wait_stats
{
max_wait_time_ms = max_wait_time_ms,
wait_per_task_ms = wait_per_task_ms,
signal_wait_time_s_raw = signal_wait_time_s - instance.signal_wait_time_s,
waiting_tasks_count_raw = waiting_tasks_count - instance.waiting_tasks_count,
wait_time_s_raw = wait_time_s - instance.wait_time_s,
ticks = (long)ticksDelta
};
result.signal_wait_time_s = result.signal_wait_time_s_raw * ticksDeltaFactor;
result.waiting_tasks_count = result.waiting_tasks_count_raw * ticksDeltaFactor;
result.wait_time_s = result.wait_time_s_raw * ticksDeltaFactor;
return(result);
}
static async Task <MetricTelemetry[]> GetPageLatchStats()
{
var query = @"select waiting_tasks_count, wait_time_s, max_wait_time_ms, signal_wait_time_s, wait_per_task_ms from qpi.wait_stats where wait_type = 'PAGELATCH_EX'";
using var connection = new SqlConnection(Configuration.ConnectionString);
var result = await connection.QueryFirstOrDefaultAsync <wait_stats>(query);
result.ticks = Stopwatch.GetTimestamp();
var delta = result.Subtract(previous);
Console.WriteLine(delta);
var metrics = new[]
{
// From DELTA
new MetricTelemetry
{
Name = "PAGELATCH_EX - waiting_tasks_count (delta)",
Sum = delta.waiting_tasks_count,
Count = 1 // Maybe this could just the time period like the ticks?
},
new MetricTelemetry
{
Name = "PAGELATCH_EX - wait_time_s (delta)",
Sum = delta.wait_time_s,
Count = 1,
},
new MetricTelemetry
{
Name = "PAGELATCH_EX - signal_wait_time_s (delta)",
Sum = delta.signal_wait_time_s,
Count = 1
},
// From DELTA RAW
new MetricTelemetry
{
Name = "PAGELATCH_EX - waiting_tasks_count_raw (delta)",
Sum = delta.waiting_tasks_count_raw,
Count = 1
},
new MetricTelemetry
{
Name = "PAGELATCH_EX - wait_time_s_raw (delta)",
Sum = delta.wait_time_s_raw,
Count = 1
},
new MetricTelemetry
{
Name = "PAGELATCH_EX - signal_wait_time_s_raw (delta)",
Sum = delta.signal_wait_time_s_raw,
Count = 1
},
new MetricTelemetry
{
Name = "PAGELATCH_EX - delta_s (delta)",
Sum = delta.ticks / (double)Stopwatch.Frequency,
Count = 1
},
// From RESULT
new MetricTelemetry
{
Name = "PAGELATCH_EX - waiting_tasks_count",
Sum = result.waiting_tasks_count,
Count = 1
},
new MetricTelemetry
{
Name = "PAGELATCH_EX - wait_time_s",
Sum = result.wait_time_s,
Count = 1
},
new MetricTelemetry()
{
Name = "PAGELATCH_EX - max_wait_time_ms",
Sum = result.max_wait_time_ms,
Count = 1
},
new MetricTelemetry
{
Name = "PAGELATCH_EX - signal_wait_time_s",
Sum = result.signal_wait_time_s,
Count = 1
},
new MetricTelemetry()
{
Name = "PAGELATCH_EX - signal_wait_time_s",
Sum = result.signal_wait_time_s,
Count = 1
},
new MetricTelemetry()
{
Name = "PAGELATCH_EX - wait_per_task_ms",
Sum = result.wait_per_task_ms,
Count = 1
}
};
previous = result;
return(metrics);
}
