Automatic Cache Invalidation
Automatic cache invalidation increases the accuracy of cached content by not serving obsolete data. It also removes the need for manual intervention every time you modify the content of the hosted files.
Automatic invalidation is triggered only in the following scenarios for files stored under File Cabinet > Web Site Hosting Files:
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When you modify the content of a hosted file
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When you overwrite a hosted file or media item
In the context of hosted files, automatic invalidation is not triggered in the following scenarios:
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When you move, delete, or rename an existing hosted file or media item
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When you upload a new file
In situations where automatic cache invalidation is not triggered, you can manually invalidate the cache as described in Cache Invalidation Request. However, in most cases, this is unnecessary because if the URL changes or is new, there is no cache present requiring invalidation.
You can view the status of the triggered cache invalidation requests on the Cache Invalidation Status page. On the Cache Invalidation Status page, you can also filter out the cache invalidation requests triggered automatically by selecting Automatic in the Request Type field. For more information, see Cache Invalidation Status.
Frequently modified files are not cached on CDN to enhance processing performance.
Group Cache Invalidation
To reduce the number of individual cache invalidation requests, group invalidation requests are created in the following scenarios:
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When you use SOAP web services to upload files to the File Cabinet.
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When you upload a
.zipfile to the File Cabinet as described in Uploading Files to the File Cabinet.
If a certain threshold limit is reached, multiple path invalidation requests might be replaced with a single wildcard invalidation request.
Cache invalidation requests that are part of a group invalidation request have the same timestamp, which can be viewed on the Cache Invalidation Status page.
To improve processing performance, automatic throttling is enabled for the automatic cache invalidation feature. Automatic throttling ensures that your environment does not generate high volume of cache invalidation requests. For example, scheduled scripts that modify files in your environment might generate high volume of cache invalidation requests, which in turn triggers automatic throttling.
In such scenarios, a cache invalidation request gets created but the automatic throttling feature disables it. Consequently, the status of such requests is displayed as Suspended on the Cache Invalidation Status page.