/// <summary>
/// Register a performance counter for collection.
/// </summary>
/// <param name="originalString">Original string definition of the counter.</param>
/// <param name="reportAs">Alias to report the counter as.</param>
/// <param name="categoryName">Category name.</param>
/// <param name="counterName">Counter name.</param>
/// <param name="instanceName">Instance name.</param>
/// <param name="usesInstanceNamePlaceholder">Indicates whether the counter uses a placeholder in the instance name.</param>
private void RegisterPerformanceCounter(string originalString, string reportAs, string categoryName, string counterName, string instanceName, bool usesInstanceNamePlaceholder)
{
ICounterValue performanceCounter = null;
try
{
performanceCounter = CounterFactory.GetCounter(originalString, categoryName, counterName, instanceName);
}
catch (Exception e)
{
// we want to have another crack at it if instance placeholder is used,
// notably due to the fact that CLR process ID counter only starts returning values after the first garbage collection
if (!usesInstanceNamePlaceholder)
{
throw new InvalidOperationException(
string.Format(
CultureInfo.CurrentCulture,
"Failed to register performance counter. Category: {0}, counter: {1}, instance: {2}.",
categoryName,
counterName,
instanceName),
e);
}
}
bool firstReadOk = false;
try
{
// perform the first read. For many counters the first read will always return 0
// since a single sample is not enough to calculate a value
performanceCounter.Collect();
firstReadOk = true;
}
catch (Exception e)
{
throw new InvalidOperationException(
string.Format(
CultureInfo.CurrentCulture,
"Failed to perform the first read for performance counter. Please make sure it exists. Category: {0}, counter: {1}, instance {2}",
categoryName,
counterName,
instanceName),
e);
}
finally
{
PerformanceCounterData perfData = new PerformanceCounterData(
originalString,
reportAs,
usesInstanceNamePlaceholder,
!firstReadOk,
categoryName,
counterName,
instanceName);
this.performanceCounters.Add(new Tuple <PerformanceCounterData, ICounterValue>(perfData, performanceCounter));
}
}
/// <summary>
/// Collects a value for a single counter.
/// </summary>
private static double CollectCounter(string coutnerOriginalString, ICounterValue counter)
{
try
{
return(counter.Collect());
}
catch (Exception e)
{
throw new InvalidOperationException(
string.Format(
CultureInfo.CurrentCulture,
"Failed to perform a read for web app performance counter {0}",
coutnerOriginalString),
e);
}
}
/// <summary>
/// Register a performance counter for collection.
/// </summary>
private void RegisterPerformanceCounter(string originalString, string reportAs, string categoryName, string counterName, string instanceName, bool usesInstanceNamePlaceholder)
{
ICounterValue counter = null;
try
{
counter = CounterFactory.GetCounter(originalString, reportAs);
}
catch
{
PerformanceCollectorEventSource.Log.CounterNotWebAppSupported(originalString);
return;
}
bool firstReadOk = false;
try
{
// perform the first read. For many counters the first read will always return 0
// since a single sample is not enough to calculate a value
var value = counter.Collect();
firstReadOk = true;
}
catch (Exception e)
{
throw new InvalidOperationException(
string.Format(
CultureInfo.CurrentCulture,
"Failed to perform the first read for web app performance counter. Please make sure it exists. Counter: {0}",
counterName),
e);
}
finally
{
PerformanceCounterData perfData = new PerformanceCounterData(
originalString,
reportAs,
usesInstanceNamePlaceholder,
!firstReadOk,
categoryName,
counterName,
instanceName);
this.performanceCounters.Add(new Tuple <PerformanceCounterData, ICounterValue>(perfData, counter));
}
}