Won Yoo's Blog : cache proxy

Application Request Routing: Benefits of caching

wonyoo — Thu, 15 Oct 2009 01:20:00 GMT

As you know, ARRv2 RC was released a few weeks ago. (To learn more about ARRv2, click here. Download x64 or x86.) With ARRv2 RC, ARR now has two cache tiers, kernel memory cache and disk cache. I think people in general understand the benefits of caching (reduced latency, reduction in bandwidth consumption, etc) but recently, a customer who has deployed ARRv2 RC in production sent me the following data. The customer is using ARR as a reverse proxy to load balance the requests to several content servers.

The data on the left is from the content servers (aggregated) and the data on the right is from ARR. In this customers environment, over the course of 4 days (duration of time in Oct when the logs have been captured), he saved approximately 100GB worth of bandwidth (160GB total bytes in ARR vs. 62GB at the content servers). Of course, your mileage may vary depending on the cache-ability of the contents that you serve, but savings of 100GB in 4 days is significant for this customer.

I was really impressed to see the "real customer" data on ARR cache performance so I figured I would share it on iis.net. If you haven't already, check out ARR and see what it can do for you in your environment. ARRv2 RC comes with GoLive license, which means it can be deployed in production.

Note: Because some of the contents are being served from the cache in ARR, if you are providing logs to your customers, you will need to gather logs from ARR as well as from the content servers to provide the complete log.

Microsoft Application Request Routing (ARR) Version 2 RC for IIS7 has been released.

wonyoo — Thu, 24 Sep 2009 19:09:00 GMT

Microsoft Application Request Routing (ARR) Version 2 RC for IIS7 has been released.

Overview:
Application Request Routing v2.0 RC is an incremental release that includes all the features from version 1.0, and adds support for disk based cache. ARR v2.0 RC comes with Go Live rights and is licensed to be deployed in production environments.

ARR v2.0 RC can be used to:
• Enhance ARR v1.0 scenarios with disk cache.
• Use ARR as an edge cache CDN/ECN environments.

Download ARRv2 RC from:
• Microsoft Application Request Routing Version 2 RC for IIS 7.0 (x86) here.
• Microsoft Application Request Routing Version 2 RC for IIS 7.0 (x64) here.

Feature list:
• Disk-based caching
In addition to the kernel memory cache in ARR Version 1, Version 2 adds support for disk-based cache, including support for a secondary network-based drive.

• Cache hierarchy management
Define and manage relationships between cache nodes, including support for the Cache Array Routing Protocol (CARP).

• Cache proxy node in CDN/ECN environment
Because ARR is a proxy-based HTTP request routing module with support for disk cache and CARP, ARR can be used as a cache proxy in a CDN/ECN environment.

• Caching compressed objects (Improved in RC)
Disk-based cache stores compressed objects so that the objects do not have to be compressed in real time for every request. In RC, ARR will gzip compress objects even if the content server does not respond with gzip content-encoding.

• Browsing cached contents using IIS Manager (Improved in RC)
Browse through cached contents across multiple drives in one consolidated graphical view in IIS Manager. In RC, the performance enhancements in the UI (inetmgr) allows browsing of cached directories and files more quickly. It also includes improvements to usability.

• Removing cached contents
Delete cached contents by matching URL patterns.

• Overriding cache-control directives
Manually override the cache-control directives in the response header to change the cache behavior.

• Warming up cache node (Improved in RC)
Proactively warm up your cache node with contents that will be in demand before they are requested. In RC, the contents can be pre-cached selectively only at the parent cache tier.

• Intelligent byte-range support
ARR converts the byte-range request into manageable segments to increase cache hit/miss ratio without sacrificing response time.

• Intelligent live request support
ARR is designed to work with Live Smooth Streaming to support live content requests without over-loading the live streaming server.

• Caching while serving response
Caching large content, such as a movie clip, may take some time. ARR Version 2 Beta 2 is capable of caching the content while serving the response immediately.

Support:
Support for the RC release is available only on the forum.

Microsoft Application Request Routing (ARR) Version 2 for IIS7 Beta 2 has been released.

wonyoo — Thu, 16 Jul 2009 23:47:00 GMT

Microsoft Application Request Routing (ARR) Version 2 for IIS7 Beta 2 has been released.

Overview:Microsoft Application Request Routing (ARR) for IIS 7.0 is a proxy-based routing module that forwards HTTP requests to application servers based on HTTP headers, server variables, and load balance algorithms. ARR Version 2 Beta 2 is an incremental release that includes all of the features from Version 1, and adds support for disk-based cache. More specifically, this feature allows IIS to compete as a cache proxy in a whole new market place:

Enhance ARR Version 1 scenarios with disk cache.
Use ARR as a cache proxy as a cache node in a CDN/ECN environment.

Use ARR as an edge/child cache node.
Use ARR as a parent cache node.

Download ARRv2 beta 2 from:

· Microsoft Application Request Routing Version 2 for IIS7 Beta 2 (x86)

· Microsoft Application Request Routing Version 2 for IIS7 Beta 2 (x64)

What’s new in ARRv2 beta 2:

Disk-based caching (Improved in Beta 2)
In addition to the kernel memory cache in ARR Version 1, Version 2 Beta 2 adds support for disk-based cache. This feature is improved in Beta 2 with an introduction to secondary cache concept.

Cache hierarchy management
Define and manage relationships between cache nodes, including support for the Cache Array Routing Protocol (CARP).

Cache proxy node in CDN/ECN environment (Improved in Beta 2)
Because ARR is a proxy-based HTTP request routing module with support for disk cache and CARP, ARR can be used as a cache proxy in a CDN/ECN environment. This feature is improved in Beta 2 with support for more advanced routing rules, such as being able to set host headers to route requests accordingly.

Caching compressed objects
Disk-based cache stores compressed objects so that the objects do not have to be compressed in real time for every request.

Browse cached contents using IIS manager (New in Beta 2)
Browse through cached contents across multiple drives in one consolidated graphical view in IIS manager.

Remove cached contents (Improved in Beta 2)
Delete cached contents by matching URL patterns.

Override cache-control directives (New in Beta 2)
Manually override the cache-control directives in the response header to change the cache behavior.

Warm up cache node (New in Beta 2)
Proactively warm up your cache node with contents that will be in demand before they are requested.

Intelligent byte-range support
ARR converts the byte-range request into manageable segments to increase cache hit/miss ratio without sacrificing response time.

Intelligent live request support (New in Beta 2)
ARR is designed to work with Live Smooth Streaming to support live content requests without over-loading the live streaming server.

Caching while serving response
Caching large content, such as a movie clip, may take some time. ARR Version 2 Beta 2 is capable of caching the content while serving the response immediately.

Support:

· Support for the beta release is available only on the forum.

Microsoft Application Request Routing (ARR) Version 2 for IIS7 Beta 1 has been released.

wonyoo — Wed, 18 Mar 2009 18:01:00 GMT

Following the ARRv1 RTW release last month, the ARR team has released ARRv2 Beta1 release today. (The "official" announcement can be found here.)

ARRv2 is an incremental release that has all the features of ARRv1, but we added a support for disk cache. What is really exciting about this feature is that now we can start thinking about using ARR as a cache proxy. (Read about the disk cache feature here.) Also, we have added support for CARP (Cache Array Routing Protocol) and cache hierarchy management that will enable customers to build a network of ARR cache nodes in CDN (Content Delivery Network)/ECN (Edge Cache Network).

You can learn more about ARRv2 Beta 1 here.

Downloads:

Microsoft Application Request Routing Version 2 for IIS 7.0 Beta 1 (x86) here.
Microsoft Application Request Routing Version 2 for IIS 7.0 Beta 1 (x64) here.

Support:

For Beta releases, the support is provided via this forum. It is also a great place to ask for feature requests as we are currently working on Beta2.