JPA/Hibernate improve batch insert performance

问题:

I have a data model that has a ONE TO MANY relationship between ONE entity and 11 other entities. These 12 entities together represent one data packet. The problem I am having is to do with the number of inserts that occur on the 'many' side of these relationships. Some of them can have as many as 100 individual values so to save one whole data packet in the database it requires up to 500 inserts.

I am using MySQL 5.5 with InnoDB tables. Now, from testing the database I see that it can easily do 15000 inserts per second when processing a batch insert (and even more with LOAD DATA, but that's not practical for this case).

Is there some way to bunch up these individual 500 inserts into, say - 5 inserts with 100 VALUES (for the 5 linked entities that each has 100 values) using Hibernate?

As Requested:

@OneToMany(mappedBy="beat", cascade=CascadeType.ALL)
@OrderBy("miliseconds ASC")
public List<AmbientLight> lights;

I should probably also mention one important piece of information - I am using Play! Framework 1.2.3

回答1:

I have managed to solve this problem by using Hibernate Sessions for each 'group' of inserts. The results are about a 7-fold reduction in time needed to save the data. Used to take approximately 2000ms to save one 'packet' and now it takes between 200ms and 300ms to do the same thing.

Just to repeat - this is valid for Play! Framework 1.2.3 - I am not sure whether, or how this applies to other frameworks or applications that utilize Hibernate.

    Session mySession = (Session) Pressure.em().getDelegate();

    for(int i = 0 ; i < data.size() ; i++){
        initializeFromJsonAndSave(data.get(i), mySession);
    }
    s.flush();
    s.clear();

The 'initializeFromJsonAndSave' method was changed so that, instead of calling the object's save() method, calls mySession.save(myNewObject).

回答2:

Here are two good answers on the subject

• Hibernate batch size confusion
• How do you enable batch inserts in hibernate?

Notice that with identity generator (it is the generator used by default with play) batch insert is disabled.