Create random Objects with primitve members in Java

I want to test the speed of different Serialization Methods. Therefore I need a class. For my purpose this class has to include only members of primitive data types and each object of the class hast to be around 80Byte size.

I tried following:

//Header = 16 Bytes
//long = 8 Byte
// => 80 Byte

public class TestClass implements Serializable {

    private long a = new Random().nextLong();
    private long b = new Random().nextLong();
    private long c = new Random().nextLong();
    private long d = new Random().nextLong();
    private long e = new Random().nextLong();
    private long f = new Random().nextLong();
    private long g = new Random().nextLong();
    private long h = new Random().nextLong();
}

And so Im creating the Objects:

for (int i = 0; i < 200000; i++) {
    TestClass object = new TestClass();
    //do something;
}

The problem here is following. This creates only around 846 Objects per ms. But I need up to 60,000 Objects per ms. Is there any solution for this?

Thanks