Steve, I have made changes based on the github comments and your comments below (https://github.com/johnaoahra80/hibernate-orm/commits/HHH-9701).
Do you want me to squash the commits down to one? Not sure how this would effect the comments you have already made on GH Thanks John On 06/04/15 04:51, Steve Ebersole wrote: > > > On Thu, Apr 2, 2015 at 4:45 AM, John O'Hara <joh...@redhat.com > <mailto:joh...@redhat.com>> wrote: > > Steve, > > I have pushed a proposal for HHH-9701 to: > https://github.com/johnaoahra80/hibernate-orm/tree/HHH-9701 > > There are a couple of areas that I would appreciate feedback; > > 1) Serialization/Deserialization - EntityEntries implementations > can be serialized and each implementation provide their own > serialization method. I have modified the serialization of > EntityEntry in EntityEntryContext to write the Implementation > class to the OutputStream so the correct class can be used to > deserialize the object stream. Is the exception handling > sufficient here, or do we need more robust handling of > deserialization exceptions? : see > > https://github.com/johnaoahra80/hibernate-orm/commit/ec9b1fa3b97131ff1e65a1cc30ff6e4f2d2c8a28#diff-b55e1e51b30abe8d3c280bb22aeb6a44R380 > > > I added some comments to that section. Also, overall I would extract > the deserialization bit into a separate method (deserializeEntityEntry). > > > 2) In our (perf team) use case, we want to be able to share the > ImmutableEntityEntry between sessions when they are referenced > cached in the 2lc. I have modified EntityEntryContext to not null > managedEntity.$$_hibernate_setEntityEntry if the EntityEntry is an > instance of ImmutableEntityEntry. Do we need to add an extra > checks here, to ensure that the entity is Reference Cached? I am > not sure how we would test that case? : see > > https://github.com/johnaoahra80/hibernate-orm/commit/ec9b1fa3b97131ff1e65a1cc30ff6e4f2d2c8a28#diff-b55e1e51b30abe8d3c280bb22aeb6a44L281 > > > It really depends on what y'all consider the trigger for using > ImmutableEntityEntry. When would the EntityPersister use the > EntityEntryFactory producing ImmutableEntityEntry instances? > a) when the entity is marked immutable? > b) when the entity is marked immutable *and* we need to cache it by > reference? > c) some other condition? > > I agree that we should only not clear that reference when the entity > is enabled for cache-by-reference. How that plays into this depends > on the answer to the above question. > > If (a), then I think that yes it makes sense to add a check to only > clear the ManagedEntity's EntityEntry reference if using > cache-by-reference. > > If (b), then the EntiytPersister is only using the EntityEntryFactory > producing ImmutableEntityEntry instances when both are true. So the > fact that an entry is an instance of ImmutableEntityEntry indicates > that we need to not clear it from the ManagedEntity. > > > > 3) Lock Mode: Steve you mentioned about not doing locking for > Immutable entities. Where is the locking implemented? Would it be > sufficient to simply set the LockMode on the ImmutableEntityEntry > to NONE/READ_ONLY when setLockMode is called? > > > > Locking is implemented in many places. > > What I had in mind, in terms of implementation for EntityEntry, is > somewhat influenced by the choice between ignore versus exception in > cases where something is not supported. Basically I had thought to > throw an exception in ImmutableEntityEntry#setLockMode or to simply > ignore the call altogether. This is not a great solution. > > It is hard for me to justify ignoring the lock request in all cases. > What does everyone else think? > > > -- John O'Hara joh...@redhat.com JBoss, by Red Hat Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United Kingdom. Registered in UK and Wales under Company Registration No. 3798903 Directors: Michael Cunningham (USA), Charlie Peters (USA), Matt Parsons (USA) and Michael O'Neill (Ireland). _______________________________________________ hibernate-dev mailing list hibernate-dev@lists.jboss.org https://lists.jboss.org/mailman/listinfo/hibernate-dev
