The gauges and reports provide easy and quick access to a high-level understanding of your application’s resource usage. If your CPU or memory usage seems higher than it should be, or if your application feels sluggish, you need more information than the gauges and reports provide.

Instruments is an application bundled with Xcode that you can use to monitor your application while it is running and gather fine-grained statistics about your application’s performance. Instruments is made up of several plug-ins that enable you to inspect object allocations, CPU utilization per function or method, file I/O, network I/O, and much more. Each plug-in is known as an Instrument. Together, they help you track down performance deficits ...

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