Invalidating the cache

05 Jan

Cache invalidation refers to process during which web cache proxies declare cached content as invalid, meaning it will not longer be served as the most current piece of content when it is requested.

Several invalidation methods are possible, including purging, refreshing and banning.

Invalidating a piece of content means telling the proxy server to no longer serve that content to clients.

The proxy can choose to either discard the content immediately, or do so when it is next requested.

If you'll want to update your objects frequently, we recommend that you primarily use object versioning for the following reasons: For more information about object versioning, see Updating Existing Objects Using Versioned Object Names.

To control the versions of objects that are served from your distribution, you can either invalidate objects or give them versioned file names.

I have some questions on cache synchronization operations.

Invalidate: Before cpu tries to read a portion of memory updated by a device, the corresponding memory needs to be invalidated.

Otherwise, when Cloud CDN re-requests the content from your backends, it may once again cache the still-incorrect content.

Each invalidation request specifies a path pattern that identifies the object or set of objects that should be invalidated.