2:56 p.m.
On 2/17/2016 3:09 PM, Marek Posolda wrote:
On 17/02/16 18:11, Bill Burke wrote:
> Currently, adding or deleting a client, or updating a realm causes
> invalidation/eviction of the realm and all clients in that realm. To
> make matters worse, the next time the realm is accessed, it queries and
> loads each client and its relationships. Why do we do this? When a
> realm invalidation happens, the cache has no idea if the realm is just
> being updated or removed entirely from the DB. With a realm removal, you
> also need to evict the cache of all clients within the realm. So, a
> cached realm MUST have a list of all clients within it. As a result,
> the more clients that get added, keycloak gets slower and slower.
> Eventually though the cache stabilizes after inserts/update/deletes
> subside and we get back to normal performance, but you can see a nasty
> blip for a little bit.
We don't need to eagerly preload all clients when realm is loaded.
Infinispan has streaming/predicate API and we are using it in many
places (see InfinispanUserSessionProvider and all the stuff in package
org.keycloak.models.sessions.infinispan.stream ). So when entry is
invalidated, we can have cacheListener, which will query infinispan to
return all cached clients of the realm and remove them. I can see that
we already have listener. So possibly we can just change this line to
use predicate query:
https://github.com/keycloak/keycloak/blob/master/model/infinispan/src/mai...
Lol, i was sort of kind of doing that doing cache.values(). This makes
it much easier with much less refactoring.
Other option is, that we can try to optimize eager preload and see if
we can reduce number of SQL queries at startup. For example, it seems
that CachedClient constructor sends SQL query to preload just realm
roles. And then each client sends another SQL query to preload his
client roles (method CachedClient.cacheRoles ). Couldn't we instead
send one SQL query to load all roles of realm (both realm and client
roles)? Maybe we can even send one big SQL query to load realm with
all it's objects :-) Possibly some FetchType.EAGER in Hibernate
entities could help here.
yeah, we should start looking into stuff like this. We can at least
reduce the number of sql calls for caching a client or realm
individually. I'm not sure how feasible it is though or how much better
it is. Realms and clients contain more than a few one to many
relationships which would make the query result HUGE if I remember how
joins work.
--
Bill Burke
JBoss, a division of Red Hat
http://bill.burkecentral.com