Thread Constructor (ThreadStart, Int32)


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Initializes a new instance of the Thread class, specifying the maximum stack size for the thread.

Namespace:   System.Threading
Assembly:  mscorlib (in mscorlib.dll)

public Thread(
	ThreadStart start,
	int maxStackSize


Type: System.Threading.ThreadStart

A ThreadStart delegate that represents the methods to be invoked when this thread begins executing.

Type: System.Int32

The maximum stack size, in bytes, to be used by the thread, or 0 to use the default maximum stack size specified in the header for the executable.

Important   For partially trusted code, maxStackSize is ignored if it is greater than the default stack size. No exception is thrown.

Exception Condition

start is null.


maxStackSize is less than zero.

Avoid using this constructor overload. The default stack size used by the Thread(ThreadStart) constructor overload is the recommended stack size for threads. If a thread has memory problems, the most likely cause is programming error, such as infinite recursion.


Beginning with the .NET Framework 4, only fully trusted code can set maxStackSize to a value that is greater than the default stack size (1 megabyte). If a larger value is specified for maxStackSize when code is running with partial trust, maxStackSize is ignored and the default stack size is used. No exception is thrown. Code at any trust level can set maxStackSize to a value that is less than the default stack size.


If you are developing a fully trusted library that will be used by partially trusted code, and you need to start a thread that requires a large stack, you must assert full trust before creating the thread, or the default stack size will be used. Do not do this unless you fully control the code that runs on the thread.

If maxStackSize is less than the minimum stack size, the minimum stack size is used. If maxStackSize is not a multiple of the page size, it is rounded to the next larger multiple of the page size. For example, if you are using the .NET Framework version 2.0 on Windows Vista, 256KB (262,144 bytes) is the minimum stack size, and the page size is 64KB (65,536 bytes).


On versions of Microsoft Windows prior to Windows XP and Windows Server 2003, maxStackSize is ignored, and the stack size specified in the executable header is used.

If you specify a very small stack size, you might need to disable stack-overflow probing. When the stack is severely constrained, the probing can itself cause a stack overflow. To disable stack overflow probing, add the following to your application configuration file.

    <disableStackOverflowProbing enabled="true"/>

.NET Framework
Available since 2.0
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