os_signpost and Untethered Recording

On my iPhone 6 and 6s Plus, in Settings -> Developer -> Logging -> Untethered Recording, alongside the Energy and Networking options there is a Signposts option too. We were hoping to be able to use this to record the signposts that our DNS Provider uses to help us understand if we are responsible for excessive energy usage while the device is idle and unplugged.


However when looking at the diagnostics in Instruments, while we can see the Energy and Network data, there are no signposts recorded.


If we run the same instruments tethered and live the signposts are shown, so we know that we are using them correctly.


I suspect that that Signposts in Settings is ignored and that signposts are not recorded during Untethered Recording. Further evidence of this is the fact that that Signposts option is not even available in later phones (e.g iPhone X and Xs).


Am I right that it is futile trying to capture Signposts in Untethered mode. Is the fact that the switch is still available on older devices just an oversight?


(BTW all devices on iOS 12.2)


It sure we help if Signposts were usable in Untethered as it would be a far simpler way of matching up energy use with what our extension is doing. Currently we have to manually check our os_log data and try and match it to what is shown in Instruments.

Replies

I'm seeing the same exact issue (iPhone 6S, iOS 12.2): signposts are not visible in untethered mode but energy logs are


Edit: radar://50577402

The signposts being referred to are the kernel's signposts (i.e. kdebug rather than os_signpost), and we use that internally for development. This option should never show up on a healthy external device. We're investigating what happened. Have either of you installed a provisioning profile from https://developer.apple.com/bug-reporting/profiles-and-logs/ ?