XADM: Enabling 4GT RAM Tuning When You Use Windows NT Server Enterprise Edition

This article was previously published under Q189293
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The information store (Store.exe) and the directory service (Dsamain.exe)have been compiled to make use of up to 3 gigabytes (GB) of addressable memory perprocess when 4GT RAM Tuning is enabled in MicrosoftWindows NT Server Enterprise Edition.

4GT RAM Tuning reallocates RAM within the 4-GB address space ofWindows NT Server from the operating system to memory-intensiveprograms. If you use 4GT RAM Tuning, a memory-intensive program can use up to 3 GBof RAM (which is a 50 percent increase over the base Windows NT Server product) sothat more data is cached and performance is increased.

This feature benefits programs (such as Exchange Server) thatrun on powerful computers with more than 2 GB of physical RAM and that cantake advantage of a larger address space.

Windows NT Server Enterprise Edition supports 4GT RAM Tuning on Intel architecture servers only.
After you install Windows NT Server Enterprise Edition, you must modify the Boot.inifile to enable 4GT RAM Tuning. To enable 4GT RAM Tuning, add the /3GB parameter to the startupline.

NOTE: This change is only effective if you are using Windows NT Server Enterprise Edition.On standard Windows NT, this flag relocates the kernel, but programsare unable to access more than 2 GB.

For example:
 [boot loader] timeout=30 default=multi(0)disk(0)rdisk(0)partition(2)\WINNT [operating systems] multi(0)disk(0)rdisk(0)partition(2)\WINNT="Windows NT Server Version 4.00" /3GB multi(0)disk(0)rdisk(0)partition(2)\WINNT="Windows NT Server Version 4.00 [VGA mode]" /basevideo /sos				
NOTE: Some of the preceding lines are wrapped for readability.

For additional information about 4GT RAM Tuning in Windows NT Server Enterprise Edition, click the article number below to view the article in the Microsoft Knowledge Base:
171793 Information on Application Use of 4GTRAM Tuning
scalability Windows NT Server/E 4GT

Article ID: 189293 - Last Review: 02/24/2014 08:33:39 - Revision: 3.3

Microsoft Exchange Server 5.5 Standard Edition

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