Deployment Recommendations for ARR
Applies To: Windows 7, Windows Server 2008, Windows Server 2008 R2, Windows Vista
This topic discusses best practices and recommendations to consider when deploying Application Request Routing (ARR). For a list and descriptions of key features introduced in ARR, see ARR Key Concepts and Features.
Disable Application Pool Idle Time-Out
The application pool idle time-out feature in IIS lets you shut down the application pool when there is inactivity. This feature lets you reuse a resource that the application pool uses and then reclaim that resource if the application pool is idle, which is particularly useful in environments where the IIS server uses shared resources to host multiple sites and applications. By default, the application pool idle time-out value is set to 20 minutes. If a worker process is not processing requests or receiving new requests for longer than 20 minutes, it will shut down. With ARR, you should disable the application pool idle time-out feature so that the application pool for ARR is constantly running and available.
For information about how to disable the application pool idle time-out feature, see Install Application Request Routing.
Disable Application Pool Recycling Conditions
The application pool recycling feature in IIS lets you periodically recycle the application pool in situations where restarting the application pool can benefit the functionality and stability of an application. For example, if an application has a slow memory leak and you want to mitigate the risk of code defects, you can recycle the application periodically. With ARR, you should disable the application pool recycling feature so that ARR is constantly available and able to respond quickly at any time.
For information about how to disable the application pool recycling feature, see Install Application Request Routing.
Separate the Cache Drive Location from the System Drive
ARR supports the use of folders as cache drive locations; however, you should separate the cache drive location(s) from the system drive. Maintaining separate cache drive location(s) will help you to manage the cache drives as the number of cached content items increases to millions of objects. Because deleting cached content from all primary cache drive locations can be a time-consuming process, you can more efficiently format the separated cache drives instead.
The following system configuration is recommended for your cache drive location:
A cache content drive that is physically separate drive from the system drive
High RPM drive (15K RPM)
If your cache drive location cannot be physically separate from the system drive, you can partition the physical drive into multiple volumes.
Disable 8.3 Name Creation
When you create 8.3 file names and directories for all long file names and directories on your NTFS partitions, the directory enumeration performance can be negatively affected. Because the ARR caching feature uses the disk drive, we recommend that you disable the creation of 8.3 names.
On Windows Server® 2008, you can only disable the creation of 8.3 names for the entire server and not per volume. On Windows Server® 2008 R2, you can disable the creation of 8.3 names per volume. For more information about 8.3 name creation on NTFS, see How to Disable the 8.3 Name Creation on NTFS Partitions.
You can disable 8.3 name creation by entering the following at a command prompt: fsutil.exe behavior set disable8dot3 1