MySQL Administrator :: 10.4 Creating Custom Health Graphs

While the pre-made status graphs can provide you with informatin of the current state of your MySQL server, there may be additionally information that you wish to visually track. The MySQL Administrator Health section allows you to add additional tabs and graphs to track any information that is contained within the Status Variables.

The first step in creating custom health graphs is to create a new page in the Health section to store your graphs. To create a new page right-click anywhere in the working area and choose the Add a Page option. You will be prompted for a page name and description and a new page will be created.

Once you have created a new page, you will need to create a group. All graphs are located within groups. For example, the Key buffer usage and Key buffer hitrate graphs are both located within a group titled Key Efficiency. To create a group, right-click within your newly created page and choose the Add a Group option.

to create a custom graph, right-click within a group and choose the Add a graph option. The following dialog will appear:

Figure 10.1. The Graph Settings dialog

Choose a caption that describes what you will be graphing, and then choose your graph type. The caption is optional and will only be displayed if the The Display Caption box is checked. After choosing a caption you will need to choose a graph type. The Line-Graph is appropriate for showing trends over time, while the Bar-Graph option will be more appropriate for showing percentage information.

The data on your graph is set using the Value Formula. You can create a formula using any of the variables available in the Status Variables and System Variables tabs. To use the value of a variable, wrap the variable name in square brackets (i.e. [com_select]), if you want the relative value of the variable prepend the square brackets with a ^ character.

For example, if we wanted to graph the percentage of temporary tables that were created on disk we could use the following formula:

  [created_tmp_disk_tables] / [created_tmp_tables]
  

If we wanted to track the number of temporary tables created on a continious basis, we could use the following as our formula:

  ^[created_tmp_tables]
  

After creating your formula, select the Value Unit that best represents your data. You can choose from Percentage, Count, Byte, and Seconds. In our examples we would have used Percentage for the first example, and Count for the second. You can also assign a caption to the value.

Once your formula is assigned you should configure the Max. Value and Min. Value for the graph, so that your data is spread evenly across your graph. You can set arbitrary values based on your estimates of how large the values will grow, and check the Autoextend Max. Value option to allow MySQL Administrator to automatically increase the Max Value setting automatically to prevent your data from extending off of your graph.

You can also set the Max. Value option by way of a formula assigned in the Max Formular field. The same syntax applies in this field as applies in the Value Formula field. For example, if you were creating a bar graph tracking the number of temporary disk tables created, you could use [created_tmp_disk_tables] as the Value Formula and [created_tmp_tables] as the Max. Formular.