On 12 January 2018 at 16:58, Vlad Mihalcea <mihalcea.v...@gmail.com> wrote: > Sure, we need to profile it first.
I had started to create a micro-benchmark for it; unfortunately I had to get back on more urgent things, but if someone is willing to let it grow further, it's on github: - https://github.com/Sanne/orm-boostrap-benchmarks > From what our users have told us, getting the metadata from the database > takes some time and my > goal was to identify whether we can do something about that. > > I'll come back once I have more info. +1 thanks! > > Vlad > > On Thu, Jan 11, 2018 at 3:05 PM, Sanne Grinovero <sa...@hibernate.org> > wrote: >> >> On 11 January 2018 at 12:39, Steve Ebersole <st...@hibernate.org> wrote: >> > I just don't see how serializing a full SessionFactory to disk is a good >> > idea. >> > >> > What do you mean by "avoiding (caching) the DB metadata retrieving the >> > part"? >> >> I'm wondering too. I would be very cautious with that: if the >> datasource connection is (temporarily) broken, because for example >> Hibernate was restarted, we don't really know which assumptions will >> still be true. The metadata is possibly no longer valid. >> >> You can't know for sure if the "development cycle" of the users isn't >> including some step which makes changes to the database, or maybe even >> updates it. I actually expect this to be common and this would cause a >> lot of trouble. >> >> If we're willing to invest to make the ORM bootstrap faster, that's >> great but we should work on identifying what is being slow and what >> can be done without making it dangerous. >> >> > >> > On Thu, Jan 11, 2018 at 2:08 AM Vlad Mihalcea <mihalcea.v...@gmail.com> >> > wrote: >> > >> >> Yes, out of the JVM. This PR allows the SF to be serialized to a file, >> >> so >> >> the next time we bootstrap, we reload the whole SF from the file >> >> instead. >> >> >> >> There are many unforeseen issues probably related to this PR and it >> >> might >> >> hurt maintenance in the long-run. >> >> >> >> For this reason, I'm going to leave the PR open as-is, and investigate >> >> whether we can bootstrap faster by avoiding (cacahing) the DB metadata >> >> retrieving the part. >> >> >> >> Vlad >> >> >> >> On Wed, Jan 10, 2018 at 7:45 PM, Steve Ebersole <st...@hibernate.org> >> >> wrote: >> >> >> >>> The SessionFactory being Serialized outside the VM? Because otherwise >> >>> it >> >>> is already "serializable" via VM serialization hooks >> >>> and org.hibernate.internal.SessionFactoryRegistry. And I'm not so >> >>> convinced we should support serializing it for "out of" VM use aside >> >>> from >> >>> what we already do which assumes the new target VM has a similarly >> >>> named >> >>> SessionFactory in its org.hibernate.internal.SessionFactoryRegistry. >> >>> >> >>> On Wed, Jan 10, 2018 at 11:20 AM Vlad Mihalcea >> >>> <mihalcea.v...@gmail.com> >> >>> wrote: >> >>> >> >>>> Hi, >> >>>> >> >>>> While reviewing old PRs we have in the ORM project, I stumbled on >> >>>> this >> >>>> one >> >>>> about serializing the SessionFactory. >> >>>> >> >>>> I created a new PR, rebased on top of the current master branch and >> >>>> all >> >>>> tests are passing fine. >> >>>> >> >>>> If anyone wants to take a look, this is the PR: >> >>>> >> >>>> https://github.com/hibernate/hibernate-orm/pull/2107 >> >>>> >> >>>> I'm thinking we should integrate it in 5.3.Alpha and stabilize it if >> >>>> there >> >>>> are some unforeseen changes. >> >>>> >> >>>> The only drawback is that, if we allow the SF to be Serializable, >> >>>> upgrading >> >>>> will be much more difficult in case we change object structure. >> >>>> We could make it clear that this might not be supported or use the >> >>>> serialVersionUID to point to Hibernate version: major.minor.patch. >> >>>> >> >>>> The main benefit is that, for a microservices architecture, Hibernate >> >>>> could >> >>>> start much faster this way. >> >>>> >> >>>> Vlad >> >>>> _______________________________________________ >> >>>> hibernate-dev mailing list >> >>>> hibernate-dev@lists.jboss.org >> >>>> https://lists.jboss.org/mailman/listinfo/hibernate-dev >> >>>> >> >>> >> >> >> > _______________________________________________ >> > hibernate-dev mailing list >> > hibernate-dev@lists.jboss.org >> > https://lists.jboss.org/mailman/listinfo/hibernate-dev > > _______________________________________________ hibernate-dev mailing list hibernate-dev@lists.jboss.org https://lists.jboss.org/mailman/listinfo/hibernate-dev
