Caching in ISA 2006 vs. Caching in MOSS
I love caching in MOSS! Combine this with secure web publishing and offloaded performance for static content and it can really make your site scale. If you haven't read up on the topic, check out these first...
Wanting to make sure your pages get cached faster? Read the warm up batch script post with sample. This can help quickly recompile pages you specify (don't be afraid to crack the batch script) when something like a content deployment publish job invalidates the .NET global assembly cache.
I highly recommend playing with the cache settings in MOSS and running perf tests. Reading the ECM blog post can help guide you through configuring it. In simple perf tests I've run the page caching was immediately 2X performance on simple page loads and obviously offloads requests that SQL would otherwise have had to address.
ISA caching can be configured independent of the caching configuration in MOSS.
Use ISA caching in addition to MOSS caching only if the following are true:
Content is static (no post-cache substitution or URL modification)
Content is 100% anonymous
(Considerations: You could have designers/contributors on another authoring web app or authoring farm with content deployment. Consider having a static web app and separate app dividing the content from the forms and dynamic content (user specific and collaborative))
Adding ISA caching can improve performance in the following scenarios:
There is a high demand for content. Adding ISA caching can improve performance where WFEs might otherwise be a bottleneck. This allows you to improve performance where the max number of WFE servers is already reached or to reduce the number of WFE servers that might otherwise be required. Offload the performance of the web servers to the ISA servers serving up static content allowing your deployment be able to serve more users.
To optimize performance over the WAN where one or more regional sites consume content hosted by a central farm. In this scenario, an ISA server at the regional site caches the page requests. Subsequent page requests are served locally instead of over the WAN. Note: WSS/MOSS 2007 has optimized the cache settings on the pages to be more explicit about what should and shouldn't be cached on the clients and hence ISA.
