[TYPO3-core] RFC: #11271: Use 2 level cache for BEgetRootLine

[Martin Kutschker]

Steffen Kamper schrieb:
> 
>> And, when do these caches expire? It's one thing to cache a rootline
>> calculation for one request, it's another to store it for a longer time
>> period. The rootline may change ANY TIME, so every move/delete action in
>> "pages" has to invalidate this cache.
>>
> 
> when create a new page the cache should be cleared for this tag, that's
> right. Now the cache_hash cache has to be cleared.
> Now using the cache framework need to enhance the clearing cache by tag,
> as we already mentioned in the other threads, mainly by Rupi.

Actually you don't want to clear the clear tag by tag. You want to clear
the cache by identifier (which is for some reason 250 and not 255 chars
long). This should be fast enough as there is an index, BUT the cache
will be clear quite often.

What's missing in this implementation is a hook for TCEmain to clear the
cache on INSERT/MOVE/DELETE. It's probabyl not necessary to clear it on
UPDATE, but I'm not sure as the extended WHERE clause is part of the
cache key (tag).

Masi