The event that is described in the "Symptoms" section of this article indicates that the Microsoft Web Proxy service (W3proxy.exe) cannot successfully allocate the memory cache that you configured in the
Cache Configuration Properties dialog box.
For example, if you have a computer with 4 GB of RAM, and you try to configure 80 percent of free memory to be used for caching, the Microsoft Web Proxy service tries to allocate 3.2 GB of RAM to the cache (4 GB x 80 /100 = 3.2 GB). Because this exceeds the maximum User mode memory size of 2 GB, this memory allocation operation is unsuccessful.
If the amount of memory that is requested is not available, Internet Security and Acceleration (ISA) Server uses an adaptive algorithm that tries to configure a progressively smaller memory cache until the operation is successful. This is to prevent the Microsoft Web Proxy service from not starting because of a user configuration error.
To view the actual amount of allocated memory for the cache, start the Performance tool, and then load the
ISA Server Cache Performance Monitor counters in System Monitor.
On computers with 4 GB of RAM or more, Microsoft Windows 2000 Advanced Server, Microsoft Windows 2000 Server Datacenter Edition, Microsoft Windows Server 2003 Enterprise Edition, and Microsoft Windows Server 2003 Datacenter Edition offer the 4-GB RAM tuning feature. This feature permits processes to benefit from more than 2 GB of RAM in the User mode space. To enable this functionality, add the
/3GB switch to the Boot.ini file on the server.
For more information, click the following article number to view the article in the Microsoft Knowledge Base:
291988�
A description of the 4 GB RAM Tuning feature and the Physical Address Extension parameter