Greenfield Technologies

Your Progress OpenEdge Database Expert

What Readprobe is NOT

You should read the results shown here with a critical eye. Just as you should any benchmark.

Something similar can be said about ATM or TPC or any other benchmark. Any number taken in isolation can be abused.

Readprobe deliberately and explicitly says nothing about IO performance. The whole point of these tests is to measure the ultimate throughput of record reads on a system which is not constrained by disks -- the database fits entirely in -B and no disk IO occurs. This is by design. Therefore fancy IO subsystems have no impact on readprobe. That doesn't mean that your application won't need them. Readprobe illustrates what you can expect to acheive by removing IO bottlenecks.

Obviously a single number should not be used in isolation to make an important decision such as "which machine to buy." Nobody should do such a thing. This is one particular number that measures a single facet of performance. There are many other important measurements to consider.

You may notice that some relatively small and inexpensive machines compare quite favorably to some very large and quite expensive machines. This is not an error. However, your particular workload and circumstances need to be taken into account in order to meaningfully compare these alternatives.

At one extreme an essentially single threaded process with no significant transactional requirement, a large record reading component which is heavily cached (perhaps the database is relatively small), no need to support large numbers of users and no hard uptime requirements may be very well served by a small "pc" type of system. Implementing a 24 processor top of the line server for such an application won't make it go any faster.

At the other end of the spectrum you may have a system whose record read requirement is similar but which is spread among many users and which has a very stringent uptime requirement. Such a system might also need a large and fast disk subsystem, multiple network adapters, very large amounts of RAM and advanced maintenance and diagnostic abilities. Many of these features are not available or are less mature in less expensive machines. In those cases you need to go with the "Big Iron".

Readprobe doesn't tell you everything about a machine. It shows one very specific metric -- how many records can be read under ideal circumstances. This happens to be a very useful thing to know. But it is not everything that you need to know nor can you make an informed decision based solely on that result. If you would like help applying these lessons to your situation contact Greenfield Technologies today to schedule an appointment!