sqlish queries for cache invalidation?

[Dridi Boukelmoune]

On Fri, Jan 26, 2018 at 6:15 PM, Nils Goroll <slink at schokola.de> wrote:
<snip>
> Dridi, I completely agree with your response, except for one thing: IMHO, bans
> are in no way less real time than purges: While the ban *lurker* processing is
> deferred, actual ban checks at lookup time happen as immediately as whatever purges.

What I meant by deferred is that objects don't become candidates for
eviction right away, so when storage runs low you may LRU-nuke objects
still alive instead of banned objects that haven't been processed yet
(lurk-able or not).

I think, but like I said I'm no expert in this area.

> Other than that, purges act on objectheads ("cache keys") affect all variants
> under that cache key. bans are checked per object (variant).

Good point, and to clarify xkey operates on objects like bans, so not
all variants may be xkey-purged at once.

Dridi