Hi,
i am facing some weird performance issues. Given this JPA Query:
public class SomeDao {
@SuppressWarnings("unchecked")
public Object getMetaData(Foo.class, long oid) {
Object o = em.find(clazz, client);
return o;
}
..
}
@Entity
@VersionColumn(name = "jpaversion")
@Table(name = "foo")
public class Foo extends BasicClientMetaData {
@Id
@Column(name = "client_oid")
private long client;
...
}
@MappedSuperclass
public class BasicClientMetaData implements MinMaxWeightAware {
@Column(name = "custnr")
private String customerNumber;
@Column(name = "maxweight")
private float maxWeightStandard;
..
}
When i call the getMetaData() of SomeDao.class (which is transactional and gets
detached when its returned to the caller), i measured 500ms for this operation.
The underlying SQL only consumes 20ms which i checked by setting the SQL log
level to TRACE.
Why is there such a difference? I mean, detaching cant be such an issue from
performance perspective. I only have this issue with exactly these kind of
classes (children of BasicClientMetaData).
But i also have other classes which have the @MappedSuperclass which work
without performance problems. Does anyone have a hint where i can look out for?
thanks.
---
regards
Marc Logemann
http://www.logemann.org
http://www.logentis.de
