The Windows XP Low Fragmentation Heap Algorithm Feature Is Available for Windows 2000

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The Low Fragmentation Heap algorithm that is available in Windows XP is now available for Windows 2000.

The Low Fragmentation Heap algorithm minimizes heap fragmentation and improves Win32 Heap allocation performance when it allocates or deallocates variable-length memory blocks. This algorithm also scales well on multiprocessor computers.
A supported hotfix is available from Microsoft. However, this hotfix is intended to correct only the problem that is described in this article. Apply this hotfix only to systems that are experiencing this specific problem.

If the hotfix is available for download, there is a "Hotfix download available" section at the top of this Knowledge Base article. If this section does not appear, submit a request to Microsoft Customer Service and Support to obtain the hotfix.

Note If additional issues occur or if any troubleshooting is required, you might have to create a separate service request. The usual support costs will apply to additional support questions and issues that do not qualify for this specific hotfix. For a complete list of Microsoft Customer Service and Support telephone numbers or to create a separate service request, visit the following Microsoft Web site: Note The "Hotfix download available" form displays the languages for which the hotfix is available. If you do not see your language, it is because a hotfix is not available for that language.


No prerequisites are required.

Restart Requirement

You must restart your computer after you apply this feature.

Hotfix Replacement Information

This hotfix does not replace any other hotfixes.

File Information

The English version of this fix has the file attributes (or later) that are listed in the following table. The dates and times for these files are listed in coordinated universal time (UTC). When you view the file information, it is converted to local time. To find the difference between UTC and local time, use the Time Zone tab in the Date and Time tool in Control Panel.
   Date        Time  Version         Size    File name   -----------------------------------------------------   11-Jun-2003 18:49 5.0.2195.6738    42,256 Basesrv.dll   17-Jan-2003 16:06 5.0.2195.6656   236,304 Cmd.exe    11-Jun-2003 18:49 5.0.2195.6660   233,232 Gdi32.dll    11-Jun-2003 18:49 5.0.2195.6741   711,440 Kernel32.dll   04-Feb-2003 20:15 5.0.2195.6661    29,264 Mountmgr.sys   11-Jun-2003 18:49 5.0.2195.6751   333,072 Msgina.dll   11-Jun-2003 18:49 5.0.2195.6741   483,600 Ntdll.dll   04-Jun-2003 17:17 5.0.2195.6752 1,695,296 Ntkrnlmp.exe   04-Jun-2003 17:18 5.0.2195.6752 1,694,336 Ntkrnlpa.exe   04-Jun-2003 17:18 5.0.2195.6752 1,715,264 Ntkrpamp.exe   04-Jun-2003 17:17 5.0.2195.6752 1,672,832 Ntoskrnl.exe   08-Apr-2003 05:54 5.0.2195.6701    90,232 Rdpwd.sys   11-Jun-2003 18:49 5.0.2195.6688   403,216 User32.dll   11-Jun-2003 18:49 5.0.2195.6745   385,808 Userenv.dll   02-Jun-2003 21:26 5.0.2195.6751 1,628,816 Win32k.sys   29-May-2003 23:25 5.0.2195.6750   181,520 Winlogon.exe   11-Jun-2003 18:49 5.0.2195.6752   243,984 Winsrv.dll   11-Jun-2003 18:49 5.0.2195.6741   711,440 Kernel32.dll   11-Jun-2003 18:49 5.0.2195.6741   483,600 Ntdll.dll   11-Jun-2003 18:49 5.0.2195.6751 1,628,816 Win32k.sys   11-Jun-2003 18:49 5.0.2195.6752   243,984 Winsrv.dll
This hotfix updates the Windows API to enable the new memory management scheme. To use this new implementation of the HeapSetInformation function, use an API call that is similar to the following:
ULONG ulHeapCompatibilityInformation ;   ulHeapCompatibilityInformation = 2;   if(HeapSetInformation(hCHeap,HeapCompatibilityInformation,&ulHeapCompatibilityInformation,      sizeof(ulHeapCompatibilityInformation))) {      wprintf(L"Heap algorithm set to %s Low-fragmentation heap(handle=0x%x)\n",          buf[ulHeapCompatibilityInformationRequested], hCHeap);   }   else      wprintf( L"Unable to set  Heap information to %s (handle=0x%x)GetLastError()= %d 0x%x\n",          buf[ulHeapCompatibilityInformationRequested],hCHeap, GetLastError(), GetLastError());   }
For additional information about how hotfix packages are named, click the following article number to view the article in the Microsoft Knowledge Base:
816915 New Naming Schema for Microsoft Windows Hotfix Packages

Article ID: 816542 - Last Review: 12/08/2015 02:14:21 - Revision: 4.5

Microsoft Windows 2000 Server, Microsoft Windows 2000 Professional Edition, Microsoft Windows 2000 Advanced Server

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