What's New in Processes and Threads

Windows 7 and Windows Server 2008 R2 include the following new programming elements for processes and threads.

New Capabilities

The 64-bit versions of Windows 7 and Windows Server 2008 R2 support more than 64 logical processors on a single computer. For more information, see Processor Groups.

User-mode scheduling (UMS) is a lightweight mechanism that applications can use to schedule their own threads. For more information, see User-Mode Scheduling.

New Functions

The following new functions are used with processors and processor groups.

Function	Description
CreateRemoteThreadEx	Creates a thread that runs in the virtual address space of another process and optionally specifies extended attributes such as processor group affinity.
GetActiveProcessorCount	Returns the number of active processors in a processor group or in the system.
GetActiveProcessorGroupCount	Returns the number of active processor groups in the system.
GetCurrentProcessorNumberEx	Retrieves the processor group and number of the logical processor in which the calling thread is running.
GetLogicalProcessorInformationEx	Retrieves information about the relationships of logical processors and related hardware.
GetMaximumProcessorCount	Returns the maximum number of logical processors that a processor group or the system can have.
GetMaximumProcessorGroupCount	Returns the maximum number of processor groups that the system can have.
GetNumaAvailableMemoryNodeEx	Retrieves the amount of memory that is available in the specified node as a USHORT value.
GetNumaNodeNumberFromHandle	Retrieves the NUMA node associated with the underlying device for a file handle.
GetNumaNodeProcessorMaskEx	Retrieves the processor mask for the specified NUMA node as a USHORT value.
GetNumaProcessorNodeEx	Retrieves the node number of the specified logical processor as a USHORT value.
GetNumaProximityNodeEx	Retrieves the node number as a USHORT value for the specified proximity identifier.
GetProcessGroupAffinity	Retrieves the processor group affinity of the specified process.
GetProcessorSystemCycleTime	Retrieves the cycle time each processor in the specified group spent executing deferred procedure calls (DPCs) and interrupt service routines (ISRs).
GetThreadGroupAffinity	Retrieves the processor group affinity of the specified thread.
GetThreadIdealProcessorEx	Retrieves the processor number of the ideal processor for the specified thread.
QueryIdleProcessorCycleTimeEx	Retrieves the accumulated cycle time for the idle thread on each logical processor in the specified processor group.
SetThreadGroupAffinity	Sets the processor group affinity for the specified thread.
SetThreadIdealProcessorEx	Sets the ideal processor for the specified thread and optionally retrieves the previous ideal processor.

The following new functions are used with thread pools.

Function	Description
QueryThreadpoolStackInformation	Retrieves the stack reserve and commit sizes for threads in the specified thread pool.
SetThreadpoolCallbackPersistent	Specifies that the callback should run on a persistent thread.
SetThreadpoolCallbackPriority	Specifies the priority of a callback function relative to other work items in the same thread pool.
SetThreadpoolStackInformation	Sets the stack reserve and commit sizes for new threads in the specified thread pool.

The following new functions are used with UMS.

Function	Description
CreateUmsCompletionList	Creates a UMS completion list.
CreateUmsThreadContext	Creates a UMS thread context to represent a UMS worker thread.
DeleteUmsCompletionList	Deletes the specified UMS completion list. The list must be empty.
DeleteUmsThreadContext	Deletes the specified UMS thread context. The thread must be terminated.
DequeueUmsCompletionListItems	Retrieves UMS worker threads from the specified UMS completion list.
EnterUmsSchedulingMode	Converts the calling thread into a UMS scheduler thread.
ExecuteUmsThread	Runs the specified UMS worker thread.
GetCurrentUmsThread	Returns the UMS thread context of the calling UMS thread.
GetNextUmsListItem	Returns the next UMS thread context in a list of UMS thread contexts.
GetUmsCompletionListEvent	Retrieves a handle to the event associated with the specified UMS completion list.
QueryUmsThreadInformation	Retrieves information about the specified UMS worker thread.
SetUmsThreadInformation	Sets application-specific context information for the specified UMS worker thread.
UmsSchedulerProc	The application-defined UMS scheduler entry point function associated with a UMS completion list.
UmsThreadYield	Yields control to the UMS scheduler thread on which the calling UMS worker thread is running.

New Structures

Structure	Description
CACHE_RELATIONSHIP	Describes cache attributes.
GROUP_AFFINITY	Contains a processor group-specific affinity, such as the affinity of a thread.
GROUP_RELATIONSHIP	Contains information about processor groups.
NUMA_NODE_RELATIONSHIP	Contains information about a NUMA node in a processor group.
PROCESSOR_GROUP_INFO	Contains the number and affinity of processors in a processor group.
PROCESSOR_NUMBER	Represents a logical processor in a processor group.
PROCESSOR_RELATIONSHIP	Contains information about affinity within a processor group.
SYSTEM_LOGICAL_PROCESSOR_INFORMATION_EX	Contains information about the relationships of logical processors and related hardware.
UMS_CREATE_THREAD_ATTRIBUTES	Specifies attributes for a UMS worker thread.
UMS_SCHEDULER_STARTUP_INFO	Specifies attributes for a UMS scheduler thread