Java Enterprise Best Practices

Know Distributed Computing Restrictions

All forms of distributed computing have two severe restrictions:

Bandwidth limitations

The amount of data that can be carried per second across the communications channel is limited. If your application transfers too large a volume of data, it will be slow. You can either reduce the volume transferred by compression or redesign, or accept that the application will run slowly. Some enterprise applications provide the additional option of upgrading the bandwidth of the communications channel, which is often the cheapest tuning option.

Latency

Any single communication is limited in speed by two factors:

• How fast the message can be transferred along the hardware communications channel

• How fast the message can be converted to and from the electrical signals that are carried along the hardware communications channel

The first factor, transferring the actual signals, is limited ultimately by the speed of light (about 3.33 milliseconds for every 1,000 kilometers), but routers and other factors can delay the signal further. The second factor tends to dominate the transfer time, as it includes software data conversions, data copying across buffers, conversion of the software message to and from electrical signals, and, potentially, retransmissions to handle packets lost from congestion or error.

The performance of most enterprise applications is constrained by latency. Data volumes are a concern, but mainly because of the cost of serializing large amounts ...