Migrating Recycling-Related Attributes

  • Article

Applies To: Windows Server 2003, Windows Server 2003 with SP1

In worker process isolation mode, you can assign one or more Web sites or applications to an application pool. Each application pool has one or more worker processes that process client requests for the Web sites and applications in the application pool. You can configure IIS to periodically recycle worker processes assigned to an application pool, which in turn recycles the Web sites and applications running in that application pool. Recycling worker processes keeps problematic Web sites and applications running smoothly, especially when it is not feasible to modify the application code. Recycling worker processes within an application pool ensures that the Web sites and applications in the application pools remain healthy, and that system resources can be recovered.

The Machine.config attributes that affect recycling-related metabase properties include:

  • timeout

  • requestLimit

  • memoryLimit

Migrating the timeout Attribute

The timeout Machine.config attribute, default value infinite, specifies the time limit after which ASP.NET starts a new worker process to take the place of the current one. The attribute is a string value in the format of hr:min:sec. To configure this value in IIS 6.0, you need to convert this format to time in minutes.

Configure the Recycling Worker Processes (in minutes) setting in IIS 6.0 to the same time value, in minutes, that is configured in the timeout Machine.config attribute.

For more information about how to configure the Recycling Worker Processes (in minutes) setting, see Configure Application Pool Recycling.

Migrating the requestLimit Attribute

The requestLimit Machine.config attribute, with a default value of infinite, specifies the number of requests after which ASP.NET starts a new worker process to take the place of the current one.

Configure the Recycling Worker Processes (in requests) setting in IIS 6.0 to the same value, in number of requests, that is configured in the requestLimit Machine.config attribute.

For more information about how to configure the Recycling Worker Processes (in requests) setting, see Configure Application Pool Recycling.

Migrating the memoryLimit Attribute

The memoryLimit Machine.config attribute, with a default value of 60 percent, specifies the percentage of physical memory that the worker process can consume before ASP.NET starts a new worker process to take the place of the current one.

Recycling based on memory consumption works slightly different in IIS 6.0, where worker processes can be recycled based on both virtual memory and physical memory. Also, the memory limit is not a percentage value, but is specified as a value in megabytes.

Configure the Maximum used memory (in megabytes) setting in IIS 6.0 to the amount of physical memory represented by the percentage specified in the memoryLimit Machine.config attribute.

Also, adjust the Maximum virtual memory (in megabytes) settings in IIS 6.0 if necessary. The Maximum virtual memory (in megabytes) is the maximum amount of virtual memory, which includes the used memory plus the reserved memory,

For more information about how to configure the Maximum used memory (in megabytes) setting, see Configure Application Pool Recycling.