Hello We use Datadog Mobile Vitals in our app and I'm trying to run some tools in Instruments for comparison. I'm not sure what tool should I use for some of those metrics: Slow Renders Description: With slow renders data, you can monitor which views are taking longer than 16ms or 60Hz to render. Instruments equivalent: Hangs including microhangs (?) CPU ticks per second Description: RUM tracks CPU ticks per second for each view and the CPU utilization over the course of a session. The recommended range is <40 for good and <80 for moderate. Instruments equivalent: CPU Profiler (?) Frozen Frames - Description: Frames that take longer than 700ms to render appear as stuck and unresponsive in your application. These are classified as frozen frames. Instruments equivalent: Hangs with > 500ms (?) Memory Utilization Description: The amount of physical memory used by your application in bytes for each view, over the course of a session. The recommended range is <200MB for good and <400MB for moderate. Instruments equivalent: Allocation (?)

Hello, I have recently been using the new Power Profiler tool introduced in Xcode 26 to analyze the power consumption of my app. My app primarily operates in the background. During a profiling session of 5 hours and 30 minutes, I observed that the app was active in the background for 2 hours and 30 minutes, while it remained in a suspended state for the remaining 3 hours. While the Power Profiler allows me to identify spikes in CPU, networking, and other resource usage at specific points, it is difficult to determine whether these values are objectively considered high. For example, in my case, the total QoS Execution Time of CPU Impact recorded during the 5 hours and 30 minutes was 12.18 seconds. I am wondering whether this is considered a good metric. Could you please advise on the following points? 1. Is there a commonly accepted or recommended ratio between app active time and CPU time that developers should aim for? 2. Are there any guidelines or reference materials on how to interpret CPU usage and other resource metrics for apps that primarily run in the background? Any insights or advice would be greatly appreciated. Thank you.

Is there an xctrace instrument capable of capturing the complete control flow of a process? So far the best I can find is high-frequency sampling, but what I need is a trace of all machine instructions executed. This is easily done on Linux/Intel using the perf tool, which provides access to Intel's hardware-assisted tracing module (ptrace). According to the arm specification, my mac mini M1 (armv8.4-a) and M4 (armv9.2-a) both have hardware support in the CoreSight ETM (embedded trace macrocell) for full instruction tracing (i.e., no sampling, no gaps, no statistics--capturing the complete execution path). But it's not clear how I can access these features, if they are supported by the macos XNU kernel at all. After hours of searching online, it's nothing but dead ends. Any suggestions for documentation or Xcode tools or open-source tools or built-in macos tools would be much appreciated!

We have 2 iPhones (16 pro - iOS 18.2, 16 regular - iOS 18.5 ) in single app mode and sometimes we need to shut them down manually. After holding Power and VolumeUp, shutdown screen appears as usual, but the slider isn't responding to touch, as well as the whole screen. After force restart using volume buttons, this issue disappears, but reappears after next phone restart. If we disable single app mode -the issue is gone and touch screen works every time on shutdown screen. Both iPhones share the same behavior. Is there any other way to reliably shut down the iPhone locally without using MDM or a way to fix this issue?

According to the ARM documentation for the CPU models available in Apple Silicon, the CoreSight implementation includes an Embedded Trace Macrocell which can perform a complete "Instruction Trace" (https://developer.arm.com/documentation/102119/0200/What-is-trace-). Although other operating systems such as Linux make this easy, we have not been able to find any tools or even a system-level API for accessing this feature of the ETM. In the "Instruments" window of Xcode 16+, there is a "Processor Trace" instrument, but this performs sampling and is totally unrelated to the Instruction Trace we need for debugging and analysis purposes. Because it produces a complete, contiguous sequence of branch instructions, the Instruction Trace is essential for identifying precise execution behaviors that are otherwise invisible to the developer. On other platforms, an alternative is debugger scripting, but we have found far too many bugs and reliability issues with the macOS implementation of lldb. Any suggestions would be greatly appreciated!

I tried using Create ML of Xcode 26.0 beta 7 to generate a model using the "Word Tagging" template, and I received the error: Training progress unavailable - Unexpected error. Using Create ML of XCode 16.4 with the same documentation, I was able to build the model and use it in a test app. I'd like to understand why Create ML of Xcode 26 no longer works.

Hello Apple team, I am using xctrace to record an Allocations trace on iOS. For example: xctrace record --template "Allocations" --launch com.example.myapp --time-limit 30s --output alloc.trace After recording, I can export the results in Allocations List format (flat list of allocations) using: xcrun xctrace export --input ./alloc.trace --xpath '/trace-toc/run/tracks/track[@name="Allocations"]/details/detail[@name="Allocations List"]' --output ./alloc.xml This works fine and produces an XML output. However, what I really need is to export the data in Call Tree format (as shown in Instruments GUI). I checked xctrace export --help, but it seems that the Allocations template only supports the List view for export, not the Call Tree breakdown. My question is: 👉 Is there a way to export an Allocations trace in XML with Call Tree details using xctrace? 👉 If not, is there an API or recommended workflow to automate this instead of exporting manually from Instruments GUI? Thanks in advance for your help!

I'm working on a custom instrument that displays intervals from os_signpost data. I'd like to color the intervals in the graph based on data from an accompanying aggregate. For example, color the interval red if its duration is greater than 3 standard deviations from the mean. Is this possible?

Hello, I am trying to investigate my apps memory usage using the instruments tool. Whenever I attach instruments my app crashes, when I have it connected to xcode as well I can see that the crash occurs in liboainject: ___lldb_unamed_symbol117 with SIGBUS. Here's what the stack looks like. Is this a known issue? Are there any workarounds or things I can do to figure out what is causing the crash?

Hello, I'm no macOS 26.1 I'm running through the example shown in the WWDC video "Optimizing CPU Performance with Instruments." After right-clicking a test, clicking "Profile...", and trying to run a processor trace I get the error in the subject. I have processor trace enabled on the CPU via system settings. I confirmed this by disabling it and re-enabling it and noting the error that appears when this is disabled is different from the one I'm now getting. This did previously work but I haven't tried since macOS 26 is released. Is there something new I need to be doing to my Xcode project settings in order for this to be working?

This is a screenshot from the Swift Task track in Xcode. I made these tasks with public actor ResourceManager { func foo() { for observer in observers { Task(name: "ResourceManager notify observers") { await notification(observer) } } } } I am confused why each of the task is showing as a separate task in the task lifetime summary. Is there a way to queue the trace in Instruments into the fact that these are indeed the same task?

I have been working on battery consumption analysis for my application, and as part of this effort, I wanted to understand how competitor apps behave under similar usage conditions. To do this, I downloaded competitor apps from the App Store and attached them to Instruments via Xcode. I then executed a defined set of manual test scenarios to simulate real user behavior. During these tests, the iPhone was connected to a Mac and charging continuously, which meant that System Power Usage logs were not generated in Instruments. However, I was able to capture detailed metrics such as: Network usage CPU load GPU activity Display and brightness impact Other runtime performance characteristics Since direct battery drain data was unavailable, I used derived analysis (with AI assistance) to estimate approximate power consumption based on the above metrics, assuming real-device (battery-powered) conditions. According to Apple documentation, System Power Usage in Instruments is not directly tied to the device’s battery percentage. Instead, it appears to be computed using contributing factors such as CPU, network, display, and other subsystem activity. This raises a few important questions about data reliability and methodology. Key questions: How reliable are Instruments-based metrics (CPU, network, display, GPU) for estimating real-world battery consumption when the device is charging? Can these metrics be safely used as a comparative baseline between competitor applications, even if absolute battery drain values are unavailable? Is the System Power Usage instrument essentially a derived model based on subsystem activity, and if so, does it remain accurate when the device is not discharging? From Apple’s perspective, is this a valid approach for relative power comparison, provided that: The same device is used OS version is identical Test scenarios are consistent and repeatable Based on these findings, would it be reasonable to proceed with instrumenting our own application, run the same scenarios, and draw conclusions using relative comparisons rather than absolute battery percentages? The intent is not to claim exact battery drain numbers, but to establish a directionally correct and repeatable comparison that can guide performance optimizations in our own application. I would like to understand whether this methodology aligns with Apple’s recommended practices, or if there are limitations or inaccuracies I should be aware of before relying on these results for decision-making.

I'm developing a library and using XCTest for unit tests. While trying to profile the test suite, I noticed that Instruments seems to report a leak every single time the async throwing setup function is called, no matter what. For example, This will report a leak: final class LeakTests: XCTestCase { override func setUp() async throws { try await super.setUp() } func testLeak() async throws { try await Task.sleep(nanoseconds: 5_000_000_000) } } This will not report a leak: final class LeakTests: XCTestCase { // override func setUp() async throws { // try await super.setUp() // } func testLeak() async throws { try await Task.sleep(nanoseconds: 5_000_000_000) } } Any ideas on why this might be happening, or should I just file a bug report? It makes it quite difficult to use the leak detection for unit tests, as it shows hundreds of leaks when the whole suite is ran.

I am a developer creating an app for iOS 16 and my app mysteriously started showing a blank screen during previews and the simulator. I profiled the app launch with Instruments, and the results said that dlopen was running on the main thread for the whole minutes of profiling:

Hi, When I run the new Processor Trace instrument on a simple C or C++ console app, it hangs in "Analyzing - Transferring data" upon finishing the measurement. When I run it without any other instrument, I get the error: Failed to stop recording session: Data Providers emitted errors: CPUTrace Any ideas what I could try, or how to get a more verbose log of this failure? Best, Ronny P.S.: I'm using a Macbook Pro M4 Pro 14". MacOs Version 15.4 Beta (24E5228e)

I am currently reviewing the tutorial documentation for the instruments. (Instruments Tutorials: https://developer.apple.com/tutorials/instruments/identifying-a-hang) It seems very useful, so I want to follow the tutorials step by step. However, I am having trouble downloading the sample project files; it appears that the 7z file is broken. (https://developer.apple.com/instruments/tutorials/downloads/InitialVersion.7z) Can anyone help me with how to download the project files properly?

As stated in the title. I am running the following code. Each time I perform an API call, I create a new instance of URLSession and use a background-configured session to allow background API calls. ` Code being executed: import Foundation // Model definitions struct RandomUserResponse: Codable { let results: [RandomUser] } struct RandomUser: Codable { let name: Name let email: String } struct Name: Codable { let first: String let last: String } // Fetcher class class RandomUserFetcher: NSObject, URLSessionDataDelegate { private var receivedData = Data() private var completion: ((RandomUser?) -&gt; Void)? private var session: URLSession! func fetchRandomUserInBackground(completion: @escaping (RandomUser?) -&gt; Void) { self.completion = completion let configuration = URLSessionConfiguration.background(withIdentifier: "com.example.randomuser.bg") session = URLSession(configuration: configuration, delegate: self, delegateQueue: nil) let url = URL(string: "https://randomuser.me/api/" )! let task = session.dataTask(with: url) task.resume() } // Data received func urlSession(_ session: URLSession, dataTask: URLSessionDataTask, didReceive data: Data) { receivedData.append(data) } // Completion func urlSession(_ session: URLSession, task: URLSessionTask, didCompleteWithError error: Error?) { defer { self.session.finishTasksAndInvalidate() } guard error == nil else { print("Error: \(error!)") completion?(nil) return } do { let response = try JSONDecoder().decode(RandomUserResponse.self, from: receivedData) completion?(response.results.first) } catch { print("Decoding error: \(error)") completion?(nil) } } }` Called in viewDidLoad, etc.: let fetcher = RandomUserFetcher() fetcher.fetchRandomUserInBackground { user in if let user = user { print("Name: \(user.name.first) \(user.name.last), Email: \(user.email)") } else { print("Failed to fetch random user.") } } In Instruments' Network instrument, I focus on my app's process, use 'Command + 3', and switch to 'List: URLSessionTasks'. Even though didCompleteWithError is called and the API call fully completes, the Duration keeps increasing, and the Success column remains '-' (neither 'Yes' nor 'No'). For non-background URLSessions, the session shows up as 'unnamed session', but for background URLSessions, it appears as 'unnamed background session 1 (XXXXXX-XXXXXX-XXXXX)'. Does this mean the session is not actually being completed? I've checked Debug Memory Graph and confirmed there is no NSURLSession memory leak, but is it possible that the app is somehow still retaining session information internally? I also suspect that Instruments may not be able to fully track background URLSession tasks.

I’m seeing inconsistent call stacks and usage percentages in the Time Profiler between two Instruments builds: • Xcode 16.0’s Instruments Version 16.0 (16A242d) • Xcode 16.3’s Instruments Version 16.0 (16E140) When I open an old .trace file recorded with the 16A242d profiler in the newer 16E140 Instruments, the call trees and percentage breakdowns no longer match. It looks like the latest Instruments now exposes or collapses different frames (e.g. system libraries, inline code) by default. I rely on these call stacks as a baseline to track performance regressions and verify optimizations over time. Unfortunately, every Xcode/Instruments update changes what I see, making it impossible to compare profiles across versions. My questions: Is there a way in Instruments 16.0 (16E140) to restore the exact call-tree view and percentage calculations that 16A242d produced? Failing that, is there a recommended workflow or tool for capturing CPU profiles in a way that remains stable and comparable, regardless of Xcode or Instruments version? Any guidance on achieving consistent, version-independent performance measurements would be greatly appreciated!

Updated Xcode from 16.2 to 16.4, running Time Profile in Instruments, it launches the trace, but does not install or load on connected device, breaks the functionality. I am unable to debug... ERROR: Connection with the remote side was unexpectedly closed : <dictionary: 0x1f3c8b6d0> { count = 1, transaction: 0, voucher = 0x0, contents = "XPCErrorDescription" => <string: 0x1f3c8b850> { length = 22, contents = "Connection interrupted" } } Domain: IXRemoteErrorDomain Code: 6 User Info: { DVTErrorCreationDateKey = "2025-08-09 00:47:53 +0000"; } -- Connection with the remote side was unexpectedly closed : <dictionary: 0x1f3c8b6d0> { count = 1, transaction: 0, voucher = 0x0, contents = "XPCErrorDescription" => <string: 0x1f3c8b850> { length = 22, contents = "Connection interrupted" } } Domain: IXRemoteErrorDomain Code: 6 IOS 18.5

I'm currently exploring Instruments for profiling and tracing on macOS 15.6.1. I know there is the "network connections" instrument which records TCP/UDP information, however it seems to not include the "lo0" (loopback) interface. Is there a way to configure it so that localhost traffic is included in the recording? as the application I'm tracing uses that and I want that information to be included in traces. The documentation for network-interface-detection schema makes no mention of how it detects interfaces. Thanks in advance.