Introduction
Performance counters allow us to monitor physical devices
such as Processor, Memory, CLR, Network, Threads etc. Windows provides
performance monitor utility to view performance counters. To open that utility
need to go to Start -> Run and type “perfmon” and press enter. Below is the screenshot
of Performance Monitor utility.
This application monitors various system components, as per above image it displays the processor time utilization. There are multiple
performance counters available to monitor different devices. Those performance
counters are grouped under categories. Below screenshot displays Add Counter
window of performance monitor utility.
Above image displays various categories like Processor,
Process, Print Queue, Power Meter etc. Each category has its own counters, as
per above image Processor category has “% C1 Time”, “% C2 Time” and so on. Category may have instances and if it has then it will be displayed in instance list. Instance list of selected category is available below the category list.
Enumerating available categories
Dotnet provides PerformanceCounterCategory class to get all
the categories of performance counters. This class is available in
System.Diagnostics namespace. GetCategories methods returns collection of
PerformanceCounterCategory. Let’s have a look on below code.
//Get all
performance categories
PerformanceCounterCategory[]
perfCats = PerformanceCounterCategory.GetCategories();
foreach (PerformanceCounterCategory category in perfCats.OrderBy(c => c.CategoryName))
{
Console.WriteLine("Category Name: {0}",
category.CategoryName);
}
Output –
Category Name: .NET
CLR Data
Category Name: .NET
CLR Exceptions
Category Name: .NET
CLR Interop
Category Name: .NET
CLR Jit
…
Category Name: Active
Server Pages
Category Name:
APP_POOL_WAS
Category Name:
ASP.NET
…
Category Name: Per
Processor Network Interface Card Activity
Category Name:
PhysicalDisk
Category Name: Print
Queue
Category Name:
Process
Category Name:
Processor
…
…
…
…
…
The above code displays all available performance counter categories order by category name.
Performance Counters by Category
Below example demonstrates how we can get all the
performance counters for given category. We can also get all the counters for
all the categories if you don’t specify category name in below code but it will
take a while to execute. So in below code I have retrieved performance counters only for "Memory" category.
//Get all
performance categories
PerformanceCounterCategory[]
perfCats = PerformanceCounterCategory.GetCategories();
//Get
single category by category name.
PerformanceCounterCategory cat
= perfCats.Where(c => c.CategoryName == "Memory").FirstOrDefault();
Console.WriteLine("Category Name: {0}", cat.CategoryName);
//Get all
instances available for category
string[]
instances = cat.GetInstanceNames();
if
(instances.Length == 0)
{
//This block will
execute when category has no instance.
//loop all the
counters available withing category
foreach (PerformanceCounter counter in cat.GetCounters())
Console.WriteLine(" Counter Name: {0}",
counter.CounterName);
}
else
{
//This block will
execute when category has one or more instances.
foreach (string instance in
instances)
{
Console.WriteLine(" Instance
Name: {0}", instance);
if
(cat.InstanceExists(instance))
//loop
all the counters available withing category
foreach
(PerformanceCounter counter in cat.GetCounters(instance))
Console.WriteLine(" Counter
Name: {0}", counter.CounterName);
}
}
Output –
Category Name: Memory
Counter Name: Page Faults/sec
Counter Name: Available Bytes
Counter Name: Committed Bytes
Counter Name: Commit Limit
Counter Name: Write Copies/sec
Counter Name: Transition Faults/sec
Counter Name: Cache Faults/sec
Counter Name: Demand Zero Faults/sec
Counter Name: Pages/sec
Counter Name: Pages Input/sec
Counter Name: Page Reads/sec
Counter Name: Pages Output/sec
Counter Name: Pool Paged Bytes
Counter Name: Pool Nonpaged Bytes
Counter Name: Page Writes/sec
Counter Name: Pool Paged Allocs
Counter Name: Pool Nonpaged Allocs
Counter Name: Free System Page Table
Entries
Counter Name: Cache Bytes
… … …
The above code returns name of the counters available in 'Memory' category. Memory category doesn’t contain any instances so it will list
all the performance counters without displaying instance name. We can also
execute same code for category which has instances. So let’s execute the
same code with “Processor” category.
PerformanceCounterCategory cat
= perfCats.Where(c => c.CategoryName == "Processor").FirstOrDefault();
Output –
Category Name:
Processor
Instance Name: _Total
Counter Name: % Processor Time
Counter Name: % User Time
Counter Name: % Privileged Time
Counter Name: Interrupts/sec
Counter Name: % DPC Time
Counter Name: % Interrupt Time
Counter Name: DPCs Queued/sec
Counter Name: DPC Rate
Counter Name: % Idle Time
Counter Name: % C1 Time
Counter Name: % C2 Time
Counter Name: % C3 Time
Counter Name: C1 Transitions/sec
Counter Name: C2 Transitions/sec
Counter Name: C3 Transitions/sec
Instance Name: 0
Counter Name: % Processor Time
Counter Name: % User Time
Counter Name: % Privileged Time
… … …
Instance Name: 1
Counter Name: % Processor Time
Counter Name: % User Time
Counter Name: % Privileged Time
… … …
As per change in category of above code, now output displays
all the performance counters available in 'Processor' category. Processor
category has three instances so it will list all the performance counters with instance name.
Reading
Performance Counter Value
PerformanceCounter class used to retrieve value of performance counter. This class is also available in System.Diagnostics namespace. We need to pass CategoryName, CounterName and
InstanceName (Optional) to PerformanceCounter class constructor or we need to
set those properties to performance counter instance explicitly. Performance counter
instance has NextValue method which can be used to retrieve the value of give
performance counter.
Let’s have a look on below code.
DispatcherTimer
timer = new DispatcherTimer();
timer.Interval = new TimeSpan(0,0,1);
timer.Tick += new EventHandler(timer_Tick);
timer.Start();
void
timer_Tick(object sender, EventArgs e)
{
using (PerformanceCounter perfCounter = new PerformanceCounter("Memory",
"Available
MBytes"))
{
float
value = perfCounter.NextValue();
Console.WriteLine("Total
Memory Available: {0} MB.", value);
}
}
Output –
Total Memory
Available: 236 MB.
Total Memory
Available: 239 MB.
Total Memory
Available: 236 MB.
Total Memory
Available: 231 MB.
Total Memory
Available: 218 MB.
Total Memory Available:
221 MB.
Total Memory
Available: 237 MB.
Total Memory
Available: 237 MB.
Adding custom categories and counters
The new counters and categories can be added and measured
through C# code. Dotnet provides PerformanceCounterCategory class to create new
category and CounterCreationData class to create new performance counter. You can create multiple counters under single
category. The create method of PerformanceCounterCategory accepts collection of
CounterCreationData. Let’s have a look on below code.
string
category = "MyCategory";
string
counter1 = "Counter1";
//Check
whether category is exist or not
if (!PerformanceCounterCategory.Exists(category))
{
//creates
collection of CounterCreationData
CounterCreationDataCollection
counterDataCollection =
new CounterCreationDataCollection();
//added new
CounterCreationData to counterDataCollection
counterDataCollection.Add(new CounterCreationData(counter1,
"My
custom counter", PerformanceCounterType.NumberOfItems32));
//Creates new category based on information and creates
counters available in counter data
collection
PerformanceCounterCategory.Create(category,
"My Category", PerformanceCounterCategoryType.SingleInstance,
counterDataCollection);
}
As per above image from performance monitor tool, MyCategory
is created and Counter1 is added to it. You can delete category by calling PerformanceCounterCategory.Delete method. To create and delete performance counters and categories you need administrative privileges.
See Also –
