DiskPart 257

We'll let the real MS experts talk about it: ------------

Configuring page files for optimization and recovery in Windows Server 2003, in Windows 2000, and in Windows NT View products that this article applies to. Article ID : 197379 Last Review : December 10, 2004 Revision : 5.0 This article was previously published under Q197379 For a Microsoft Windows XP version of this article, see 314482 SUMMARY By default, Windows places the page file on the boot parbreastion where the operating system is installed. To determine the size of the pagefile multiply the amount of physical RAM by 1.5 to a maximum of 4095 MB. However, placing the pagefile on the boot parbreastion does not optimize performance because Windows has to perform disk I-O on both the system directory and the pagefile. Therefore, it is recommended that you place the pagefile on a different parbreastion and different physical hard disk drive so that Windows can handle multiple I-O requests more quickly.

However, completely removing the pagefile from the boot parbreastion does not allow Windows to create a crash dump file (Memory.dmp) should a kernel mode STOP error occur. Not having this crash dump file could lead to extended server downtime should the STOP require a debug to be performed.

The optimal solution, other than the solution of adding more physical memory, is to do the following: 1. Create one pagefile on the boot parbreastion by using the default settings. 2. Create another pagefile on a less frequently used parbreastion on a separate physical disk or RAID volume. You can create additional pagefiles for each separate physical disk or RAID volume.

Windows will use the pagefile on the less frequently used parbreastion over the pagefile on the heavily used boot parbreastion. Windows uses an internal algorithm to determine which page file to use for virtual memory management. In the above scenario, the following goals of the page file would be served: The system will be properly configured to capture a Memory.dmp file should the computer experience a kernel mode STOP error. The page file on the less frequently used parbreastion will be used the majority of the time because it is not on a busy parbreastion. MORE INFORMATION Another advantage of using a pagefile on its own parbreastion is that the pagefile will not become fragmented. If the pagefile is on a parbreastion with other data, the pagefile might experience fragmentation as it expands to satisfy the extra virtual memory required. A defragmented pagefile leads to faster virtual memory access and improves the chances of capturing a dump file without significant errors.

How to configure paging files for optimization and recovery in Windows XP View products that this article applies to. Article ID : 314482 Last Review : May 13, 2004 Revision : 1.0 This article was previously published under Q314482 For a Microsoft Windows NT and Windows 2000 version of this article, see SUMMARY The paging file (Pagefile.sys) is a hidden file on your computer's hard disk that Windows XP uses as if it were random access memory (RAM). The paging file and physical memory make up virtual memory. By default, Windows stores the paging file on the boot parbreastion (the parbreastion that contains the operating system and its support files). The default, or recommended, paging file size is equal to 1.5 times the total RAM. This article discusses how to configure the paging file for system optimization and recovery.

To enhance performance, it is good practice to put the paging file on a different parbreastion and on a different physical hard disk drive. That way, Windows can handle multiple I-O requests more quickly. When the paging file is on the boot parbreastion, Windows must perform disk reading and writing requests on both the system folder and the paging file. When the paging file is moved to a different parbreastion, there is less compebreastion between reading and writing requests.

However, if you remove the paging file from the boot parbreastion, Windows cannot create a dump file (Memory.dmp) in which to write debugging information in the event that a kernel mode Stop Error message occurs. This could lead to extended downtime if you must debug to troubleshoot the Stop error message.

The optimal solution is to create one paging file that is stored on the boot parbreastion, and then create one paging file on another parbreastion that is less frequently accessed on a different physical hard disk if a different physical hard disk is available. Additionally, it is optimal to create the second paging file so that it exists on its own parbreastion, with no data or operating-system-specific files. By design, Windows uses the paging file on the less frequently accessed parbreastion over the paging file on the more heavily accessed boot parbreastion. An internal algorithm is used to determine which paging file to use for virtual memory management.

When you put a paging file on its own parbreastion, the paging file does not become fragmented, and this counts as another definite advantage. If a paging file resides on a parbreastion that contains other data, it may experience fragmentation as it expands to satisfy the extra virtual memory that is required. An unfragmented paging file leads to faster virtual memory access and to a greater chance of a dump-file capture that is free of significant errors.

If you follow these recommendations, you meet the following paging file configuration goals for optimization and recovery: The system is correctly configured to capture a Memory.dmp file if the computer experiences a kernel mode Stop Error. The paging file on the less frequently accessed parbreastion is used most frequently because it is on a parbreastion that is least busy.

For most UNIX, the two times memory rule works best, though some implementations will have formulas based on the use of the memory and hardware available.

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