I Want to Know if Servers Respond Quickly

The Response Time Histogram displays response times for selected servers.

To view the histogram, select ANALYZE > Graphs > Statistics > Histogram.

The histogram consists of 10 individual bars.

Each bar represents the percentage of replies within a given milliseconds interval.

This way you can very quickly find out if a particular server is potentially overloaded—like the blue one in the example image.

Tip

In the example, we use the histogram to spot a potentially overloaded server. However, the main benefit of the histogram is that it helps you verify if a high average response time is caused by a major or a minor ratio of the total requests. This in turn can help you determine whether a high average response time is really a problem.

Important

How can a high average response time not be a problem?

If a high average response time is caused by a few responses in the 2000-500000 milliseconds interval while the majority of responses are in the 0-10 milliseconds interval, the high average may not be a problem. This of course also depends on your type of organization, which types of applications and servers you run, how business-critical your applications are, etc.