Isn't Hibernate ORM already providing such a service via the Session/Persistence context/"L1" container ?
We might be able to take advantage of existing events to control the batching on MongoDB. On 25 April 2012 08:35, Emmanuel Bernard <emman...@hibernate.org> wrote: > I don't think we need an actual multi threaded cache. the flush operation in > Hibernate is not multi threaded, neither is the session. > A simple Map (or a better append only structure) will suffice, I think. > > On 25 avr. 2012, at 09:32, Guillaume SCHEIBEL wrote: > >> Hi all, >> >> What do you think about using the Ehcache module to store the data between 2 >> flushes ? >> I will open a JIRA about this point if it has not already been done. >> >> Guillaume >> >> 2012/4/25 Emmanuel Bernard <emman...@hibernate.org> >> Hi Alan and all, >> >> I have been researching the spikes issue you encounter in the stress test >> from a theoretical point of view. >> You were trying a different associations storage approach (splitting >> associations as one row per document rather than the whole association per >> document). Does that return better results? >> >> I am skeptical for a few reasons. MongoDB has a global write lock per mongod >> process (they are working on a more fine grained solution). So if the spikes >> are due to lock contention, shuffling data won't help much. Also make sure >> you use MongoDB 2.0 instead of 1.8 as they yield lock on page fault which >> should solve a lot of these spikes problems. >> >> I have found this blog entry to be quite insightful >> http://blog.pythonisito.com/2011/12/mongodbs-write-lock.html >> >> Generally speaking, if all data can stay in memory, MongoDB should behave >> wonderfully. >> >> Which leads to my demo and the time difference between Infinispan 5s and >> Mongodb 20s. I can see several reasons: >> >> - we don't really batch operations in the mongodb dialect and we should. >> We should accumulate operations and apply them at the end of the flush >> operation in one batch. That will require some new infrastructure from OGM's >> engine though >> to tell the dialect when to "flush". >> - my VM might swap memory on disk which would explain the difference >> - or it could be that Infinispan is simply 4 times faster which would not be >> too surprising as Infinispan is in-process. >> >> Emmanuel >> _______________________________________________ >> 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
