PERFORMANCE_INFORMATION structure (psapi.h)

Contains performance information.

Syntax

typedef struct _PERFORMANCE_INFORMATION {
  DWORD  cb;
  SIZE_T CommitTotal;
  SIZE_T CommitLimit;
  SIZE_T CommitPeak;
  SIZE_T PhysicalTotal;
  SIZE_T PhysicalAvailable;
  SIZE_T SystemCache;
  SIZE_T KernelTotal;
  SIZE_T KernelPaged;
  SIZE_T KernelNonpaged;
  SIZE_T PageSize;
  DWORD  HandleCount;
  DWORD  ProcessCount;
  DWORD  ThreadCount;
} PERFORMANCE_INFORMATION, *PPERFORMANCE_INFORMATION, PERFORMACE_INFORMATION, *PPERFORMACE_INFORMATION;

Members

cb

The size of this structure, in bytes.

CommitTotal

The number of pages currently committed by the system. Note that committing pages (using VirtualAlloc with MEM_COMMIT) changes this value immediately; however, the physical memory is not charged until the pages are accessed.

CommitLimit

The current maximum number of pages that can be committed by the system without extending the paging file(s). This number can change if memory is added or deleted, or if pagefiles have grown, shrunk, or been added. If the paging file can be extended, this is a soft limit.

CommitPeak

The maximum number of pages that were simultaneously in the committed state since the last system reboot.

PhysicalTotal

The amount of actual physical memory, in pages.

PhysicalAvailable

The amount of physical memory currently available, in pages. This is the amount of physical memory that can be immediately reused without having to write its contents to disk first. It is the sum of the size of the standby, free, and zero lists.

SystemCache

The amount of system cache memory, in pages. This is the size of the standby list plus the system working set.

KernelTotal

The sum of the memory currently in the paged and nonpaged kernel pools, in pages.

KernelPaged

The memory currently in the paged kernel pool, in pages.

KernelNonpaged

The memory currently in the nonpaged kernel pool, in pages.

PageSize

The size of a page, in bytes.

HandleCount

The current number of open handles.

ProcessCount

The current number of processes.

ThreadCount

The current number of threads.

Requirements

Requirement Value
Minimum supported client Windows XP [desktop apps only]
Minimum supported server Windows Server 2003 [desktop apps only]
Header psapi.h

See also

GetPerformanceInfo

Memory Performance Information