Just a word of caution, which may seem obvious to some but could trip someone (as it did me): those using CFCACHE action="flush" expireurl="somevalue", note that if you used a KEY to create the cache, then you MUST specify that KEY in the flush operation as well (adding it to the tag I listed above).
It would be really nice if the CFACHE action="flush" could be extended to return a count of how many items were flushed, since for now it returns no output, so you can't know if you did or did not succeed in flushing anything. This returned count could be done via a new attribute that would name a variable to hold the count, or it could let us name a variable to hold a struct, if perhaps there may be other info that could be returned. While the old disk-based cfcache page caching may not have been well-suited to returning such a count, this new CF9 ehcache-based page caching does indeed suit getting this information, it would seem.
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