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When you bring up an isolate screen—for example, by clicking the name of the isolate on the VM screen—you see information about that isolate.

The following screenshot shows the top of an isolate screen for a root isolate, profile.dart$main:

List of isolates on the VM screen

This summary tells you whether the isolate is running (and what expression, if any, was being executed at the moment of sampling) and provides links to screens for browsing aspects of the isolate, such as the debugger and the CPU profiler.

A pie chart shows the breakdown of the activities of the VM. For more information on the meaning of these activities, see User and VM Tags.

If you have paused the isolate—by specifying the --observe, --pause-isolates-on-start, or --pause-isolates-on-exit flag— you can continue the process by going to the debugger and typing resume.

The link for resuming the isolate

After the list of libraries used by the isolate is a graph that is updated approximately every two seconds. The graph, which shows where the CPU is spending its time at the moment of each sample, looks something like this:

A sample root isolate screen showing the stats

As you can see in the screenshot, this isolate is primarily processing Dart code.

Below the graph is an expression evaluator field.

The Evaluate text field for an isolate

For more information on how to use this field, see Evaluating Expressions.

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