Network Performance: Tuning Your Network

You have two ways to tune your network when you want to improve performance. The first is to think about it a bit, take a guess at what may improve performance, try it, and see whether the network seems to run faster. This approach is how most people go about tuning the network.

Then you have the compulsive way, which is suitable for people who organize their sock drawers by color and their food cupboards alphabetically by food groups. The compulsive approach to tuning a network goes something like this:

  1. Establish a method for objectively testing the performance of some aspect of the network.

    This method is benchmarking, and the result of your benchmark is a baseline.

  2. Change one variable of your network configuration and rerun the test.

    For example, suppose you think that increasing the size of the disk cache can improve performance. Change the cache size, restart the server, and run the benchmark test. Note whether the performance improves, stays the same, or becomes worse.

  3. Repeat Step 2 for each variable that you want to test.

Here are some salient points to keep in mind if you decide to tune your network the compulsive way:

  • If possible, test each variable separately. In other words, reverse the changes you made to other network variables before proceeding.

  • Write down the results of each test. That way, you have an accurate record of the impact that each change made on your network’s performance.

  • Be sure to change only one aspect of the network each time you run the benchmark. If you make several changes, you won’t know which one caused the change. One change may improve performance, but the other change may worsen performance so that the changes cancel each other out — kind of like offsetting penalties in a football game.

  • If possible, conduct the baseline test during normal working hours. That way, the network is undergoing its normal workload.

  • To establish your baseline performance, run your benchmark test two or three times to make sure that the results are repeatable.