#WHAT DOES IT MEAN FOR AN APP TO NAP MAC FULL#

See Inform the System About Lengthy User-Initiated Activities in Prioritize Work at the App Level. When your app tells the system the user has initiated a long-running operation that the user expects to complete “now,” the system does not put your app in App Nap. When your app communicates that it’s performing discretionary activities, the system efficiently puts your app in App Nap.

You can also help the system determine when to put your app in App Nap by distinguishing between important user-initiated activities and your app’s discretionary or asynchronous activities. See Notify Your App When Visibility Changes and Notify Your App When Active State Changes. The most effective way to enhance App Nap is for your app to listen for notifications that it’s no longer in active use and to suspend energy-intensive work as quickly as possible-well before the system puts the app in App Nap. However, your app knows the most about the importance of its activity, and shouldn’t rely on App Nap to put it into an idle state. Fortunately, with very little effort, you can enhance its capabilities, actively reducing your energy footprint and further lengthening the time users can use their device without plugging into power.īy default, your app becomes eligible for App Nap if it’s not actively engaged with the user and hasn’t updated a visible window for some length of time.

But App Nap can’t make up for the energy effects of poorly designed apps. On the Energy Impact timeline graph (see Figure 3-4), green bars and/or a lack of utilization and CPU wake overhead bars indicate when the app is in App Nap.įigure 3-4Energy Impact timeline with an app in App Nap Enhancing App NapĪpp Nap is automatic in OS X you don’t need to do anything special for it to work with your app. Open the debug navigator (choose View > Navigators > Show Debug Navigator), and select the Energy Impact gauge. When you build and run your app in Xcode, you can monitor it with the Energy Impact gauge. Figure 3-3 shows an app that’s currently in App Nap.įigure 3-3Activity Monitor showing App Nap status for an app Click the Energy button, and view the status of your app in the App Nap column. Launch your app with the Activity Monitor app (found in /Applications/Utilities) running. Use the Energy Impact gauge in Xcode and the Energy pane in the Activity Monitor app to determine whether your app is in App Nap.Īctivity Monitor. When the user brings the app to the foreground or when the app receives an XPC message or an Apple event, the app is automatically taken out of App Nap and resumes normal execution. When the above conditions are met, OS X may put the app in App Nap. It hasn’t taken any IOKit power management or NSProcessInfo assertions It hasn’t recently updated content in the visible portion of a window Generally, an app is a candidate for App Nap if: These heuristics take into account factors such as drawing activity, event processing, audio playback, foreground or background state, and app type.

OS X uses a set of heuristics to determine when to put an app in App Nap. See Notify Your App When Active State Changes and Notify Your App When Visibility Changes. Don’t rely on App Nap to get your app to fully idle. They primarily reduce a non-foreground app’s impact on other apps. The preceding measures do not necessarily save energy. I/O throttling, which reduces the rate at which the app can read or write data from a device while foreground apps need the device Timer throttling, which reduces the frequency with which the app’s timers are fired Priority reduction, which reduces the process priority of the app so it receives a smaller share of available processor time

#WHAT DOES IT MEAN FOR AN APP TO NAP MAC FULL#

When the user resumes interacting with the app, OS X instantly shifts the app back to full speed, as shown in Figure 3-2.įigure 3-1Zero energy impact of an app in App Nap Figure 3-2High energy impact of an app not in App Napįor any app that's not performing important user work, App Nap triggers a number of measures, including: The energy impact of App Nap is illustrated in Figure 3-1. By taking a proactive approach to reaching idle, you can enhance App Nap’s features by reducing the amount of work it has to do. However, you need not-and should not-wait for App Nap to start suspending your app’s activities. App Nap conserves battery life by regulating the app’s CPU usage and by reducing the frequency with which its timers are fired. If an app isn’t performing user-initiated work such as updating content on screen, playing music, or downloading a file, the system may put the app in App Nap. When the user isn’t interacting with your app, ideally, your app is absolutely idle.

What does it mean for an app to nap mac