Performance bottleneck with EclipsLink 2.0 - jpa

Question

Recently while I was using EclipsLink 2.0 I run into performance bottleneck problem with my implementation of persisting objects.
To be more specific I used to have the following implementation:
#Entity
#Table(name = "CUSTOMERS")
public class CustomerEntity implements Serializable {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
private volatile Long id;
#Column(nullable = false, unique = true)
private String name;
private static final long serialVersionUID = 6952530957072210017L;
private String custGroup;
private String address;
private String nameOfFirstPerson;
private String contactPerson;
private String phone;
private String fax;
private String email;
private String comments;
private String defaultCustomer;
private volatile boolean delayedPaymentAllowed;
private volatile long periodOfDelayedPaymentAllowed;
private volatile boolean restrictionsOnDelayedPayment;
private volatile double maxAmoutPemittedSom;
private volatile double maxAmoutPemittedYE;
private transient String salesPointName;
#Column(length=25483)
private HashMap<String, PriceItem> totalBalance;
#Column(length=25483)
private HashMap<String, PriceItem> totalBalanceUsd;
private transient boolean valueChanged = false;
#OneToMany(mappedBy = "supplier")
private Collection<PurchaseInvoiceEntity> purchaseInvoices;
#OneToMany(mappedBy = "receiver")
private Collection<SalesInvoiceEntity> salesInvoices;
#OneToMany(mappedBy = "payer")
private Collection<PayInSlipEntity> payInSlips;
#OneToMany(mappedBy = "recipient")
private Collection<PaymentOrderEntity> paymentOrders;
#OneToMany(mappedBy = "recipient")
private Collection<WriteOffEntity> writeOffs;
#ManyToOne()
private ResponsiblePersonForDebtEntity responsiblePersonForDebt;
#ManyToOne
private CustomerGroupEntity customerGroup;
public CustomerEntity() {
valueChanged = false;
}
...
}
and while each time I was adding an instance of new document into appropriate Collection while inserting a new instance of document into a table I detected that it takes too long to insert the document. I come across of this problem while I was using profiler module of netbeans ide 6.9. Actually I was using these collections in order to check for emptiness with related documents.

Answer 1

In order to tackle the problem I simply applied the following solution:
I simply removed document references :
#OneToMany(mappedBy = "supplier")
private Collection purchaseInvoices;
#OneToMany(mappedBy = "receiver")
private Collection salesInvoices;
#OneToMany(mappedBy = "payer")
private Collection payInSlips;
#OneToMany(mappedBy = "recipient")
private Collection paymentOrders;
#OneToMany(mappedBy = "recipient")
private Collection writeOffs;
from the CusotmerEntity:
#Entity
#Table(name = "CUSTOMERS")
public class CustomerEntity implements Serializable {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
private volatile Long id;
#Column(nullable = false, unique = true)
private String name;
private static final long serialVersionUID = 6952530957072210017L;
private String custGroup;
private String address;
private String nameOfFirstPerson;
private String contactPerson;
private String phone;
private String fax;
private String email;
private String comments;
private String defaultCustomer;
private volatile boolean delayedPaymentAllowed;
private volatile long periodOfDelayedPaymentAllowed;
private volatile boolean restrictionsOnDelayedPayment;
private volatile double maxAmoutPemittedSom;
private volatile double maxAmoutPemittedYE;
private transient String salesPointName;
#Column(length = 25483)
private HashMap<String, PriceItem> totalBalance;
#Column(length = 25483)
private HashMap<String, PriceItem> totalBalanceUsd;
private transient boolean valueChanged = false;
#ManyToOne()
private ResponsiblePersonForDebtEntity responsiblePersonForDebt;
#ManyToOne
private CustomerGroupEntity customerGroup;
public CustomerEntity() {
valueChanged = false;
}
.....}
while checking for references for the documents I used JPA query while editing or deleting CustomerEntity.
This simple change removed the most affecting performance problem.
Side Note:
Please while using performance profiler include a check for package methods too(eclipslink for ex.)

Answer 2

For performance and scalability issues in JPA please read or listen S"Strategies and Best Practices for Highly Scalable Java Persistence Applications" by Gordon Yorke.