SignalFx lets you put any number of plots that you want into the same chart, the better to correlate the data that you have. At the end of this tutorial, you will understand how to add multiple plot lines to the same chart, and to add a second y-axis.
This tutorial is based on sample data that is being sent into trials created after May 28, 2015. If your trial or organization was created before that, then this does not apply.
This document assumes you know how to create a chart in SignalFx, apply one or more analytics functions, and save a chart to a dashboard. You can learn how to do that by reviewing Welcome to SignalFx - Part 1, Chart 1.
Create a chart and choose your first metric
To get started, create a new chart and choose the transaction count metric, demo.trans.count, from among the three metrics we are sending to your organization:
Then, apply the sum:aggregation function and annotate the chart as desired.
Choose your second metric
Next, click into the enter signal field and select the second metric. Let’s use demo.trans.latency in this case, and apply the mean:aggregation function to it.
Choose a different color for your second metric
To choose a different color, select Color by: Metric in the right hand side of the screen.
You should see different colors for your two metrics. Now, go and modify the labels for the metrics so that you can more easily distinguish between them in the legend. To do this, click on the pencil icon next to the plot label (A or B), then edit the text.
When you are done, you will see the labels you edited in the legend.
Change the y-axis for your second metric
When you look at the legend for this chart, you will notice that one metric is consistently above 1,000, while the other is in the range of 200 or thereabouts. In situations like this, it is often useful to use a second y-axis, so that you can see the variations for each metric more clearly.
To choose a second y-axis, click on the Y-axis 1 label to the right hand side of plot line B, then select Y-axis 2.
Your plot will now use a different scale for each metric, giving you insight into how they vary with respect to one another.
Annotate your chart
Now that you have your metrics displaying properly, it’s time to annotate it so that your chart will be understandable by other people who see it. To add a chart name and description, click into the Chart Name field and change it to something concise and descriptive, like ‘Total transactions vs. average latency’, then click into the Chart description field to provide more information.
Save your chart
To save, click on the Save and Close button in the upper right hand corner.
And that’s it!