PerformanceCounter.IncrementBy Method (Int64)


Increments or decrements the value of the associated performance counter by a specified amount through an efficient atomic operation.

Namespace:   System.Diagnostics
Assembly:  System (in System.dll)

public long IncrementBy(
	long value


Type: System.Int64

The value to increment by. (A negative value decrements the counter.)

Return Value

Type: System.Int64

The new counter value.

Exception Condition

The counter is read-only, so the application cannot increment it.


The instance is not correctly associated with a performance counter.


The InstanceLifetime property is set to Process when using global shared memory.


An error occurred when accessing a system API.


The platform is Windows 98 or Windows Millennium Edition (Me), which does not support performance counters.

.NET Framework
Available since 1.1

This method is thread safe.

You can write only to custom counters. All system counters are read-only.


The Increment, IncrementBy, and Decrement methods use interlocks to update the counter value. This helps keep the counter value accurate in multithreaded or multiprocess scenarios, but also results in a performance penalty. If you do not need the accuracy that interlocked operations provide, you can update the RawValue property directly for up to a 5 times performance improvement. However, in multithreaded scenarios, some updates to the counter value might be ignored, resulting in inaccurate data.


If the value forthe InstanceLifetime property is Process and the performance counter category was created with .NET Framework version 1.0 or 1.1, an InvalidOperationException is thrown. Performance counter categories created with earlier versions use global shared memory, and the value for InstanceLifetime must be Global. If the category is not used by applications running on versions 1.0 or 1.1 of the .NET Framework, delete and recreate the category.

The following code example demonstrates how to use the IncrementBy method to add increments to a counter. This code example is part of a larger example for the PerformanceCounter class.

private static void CollectSamples(ArrayList samplesList)

	Random r = new Random( DateTime.Now.Millisecond );

	// Loop for the samples.
	for (int j = 0; j < 100; j++) 

		int value = r.Next(1, 10);
		Console.Write(j + " = " + value);



		if ((j % 10) == 9) 
			samplesList.Add( avgCounter64Sample.NextSample() );




for reading the performance counter category if the ReadOnly property is true. Associated enumeration: PerformanceCounterPermissionAccess.Read.


for writing the performance counter category if the ReadOnly property is false. Associated enumeration: PerformanceCounterPermissionAccess.Write.

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