hangs on "signpost_notificationd Skylight"

Looks like this framework is located here:

/System/Library/PrivateFrameworks/SignpostNotification.framework

What do we know about this framework?

Upon poking around, I think these are binaries only.

https://developer.apple.com/documentation/foundation/bundle

https://developer.apple.com/library/content/documentation/MacOSX/Conceptual/BPFr ameworks/Frameworks.html#//apple_ref/doc…

I also observe the same problems. My symptom is that new Chrome tabs seem to freeze up. killing the process indeed seems to help.

Am fairly certain the errors are related to the rewriting of Metal2 to handle the newly added support for eGPU in 10.13.4. Noticed 2 new Dameons / Agents in 10.13.4 not in 10.13.3. Called SafeEjectGPUservice and SafeEjestGPUAgent. Interesting, both of these are USER owned although my system does not support eGPU.

Try doing a chat session with Apple Support. I started last night but it was too late to continue session. Keep me informed please.

Error issue is persistent for me as well, not just with Safari but with WIFI turned off as well, console error message is as follows: "SkyLight error default 0 is not a valid connection ID". Named Process-"signpost_notificationd"

Searching for answer to fix, Apple did not fix this in recent update 10.13.4 High Sierra ....still looking for fix!

Same here on my MBP:

Analysis of sampling signpost_notificationd (pid 199) every 1 millisecond

Process: signpost_notificationd [199]

Path: /System/Library/PrivateFrameworks/SignpostNotification.framework/Versions/A/XPC Services/signpost_notificationd.xpc/Contents/MacOS/signpost_notificationd

Load Address: 0x104adc000

Identifier: signpost_notificationd

Version: ???

Code Type: X86-64

Parent Process: launchd [1]

Date/Time: 2018-04-04 11:17:42.005 -0700

Launch Time: 2018-03-30 22:56:16.013 -0700

OS Version: Mac OS X 10.13.4 (17E199)

Report Version: 7

Analysis Tool: /usr/bin/sample

Physical footprint: 1296K

Physical footprint (peak): 1344K

----

Call graph:

2663 Thread_1968 DispatchQueue_11: com.apple.root.default-qos.overcommit (concurrent)

+ 2663 _dispatch_sig_thread (in libdispatch.dylib) + 53 [0x7fff50b8fd10]

+ 2663 _dispatch_sigsuspend (in libdispatch.dylib) + 21 [0x7fff50b8fd25]

+ 2663 __sigsuspend_nocancel (in libsystem_kernel.dylib) + 10 [0x7fff50d0e02a]

2663 Thread_1632769

+ 2663 start_wqthread (in libsystem_pthread.dylib) + 13 [0x7fff50ed4be9]

+ 2663 _pthread_wqthread (in libsystem_pthread.dylib) + 1035 [0x7fff50ed5009]

+ 2663 __workq_kernreturn (in libsystem_kernel.dylib) + 10 [0x7fff50d0e292]

2663 Thread_1632858

2663 start_wqthread (in libsystem_pthread.dylib) + 13 [0x7fff50ed4be9]

2663 _pthread_wqthread (in libsystem_pthread.dylib) + 1035 [0x7fff50ed5009]

2663 __workq_kernreturn (in libsystem_kernel.dylib) + 10 [0x7fff50d0e292]

Total number in stack (recursive counted multiple, when >=5):

Sort by top of stack, same collapsed (when >= 5):

__workq_kernreturn (in libsystem_kernel.dylib) 5326

__sigsuspend_nocancel (in libsystem_kernel.dylib) 2663

Binary Images:

--can be provided if needed.

Can confirm. Though it only lasts until next reboot. Seeing the same behavior with a client's iMac 21" Mid-2011 on 10.13.4 (cannot confirm if it exhibits on 10.13.3; went from 10.13.2 where I hadn't noticed it to 10.13.4.), with Wi-Fi on, on but not connected, and off. Also booted into Safe mode, and booted with SIP disabled, hoping something might "fix" itself, no go.

So good catch, P.Phillips, on the Force Quit "workaround".

Though this is just ridiculous… seeing a TON of other Console errors too, from apsd to Sandbox violations to trustd. Just ridiculous to see so much low hanging fruit on a release that tested as long as 10.13.4 did.

Update: Once I force-killed signpost_notificationd, looks like the same error messages are now posted by Google Chrome Helper. I couldn't find any way to disable that, so I guess I need to use Safari.

Have done erase and reinstall and then a clean 10.13.4 just to see if this issue was caused by upgrade process.

Sad to say, the persistent error message continues to overwhelm console.

Still searching for cause and solution.

Similer issue: Console is getting slammed with "

Near this error:

Have posted on Macrumors, this issue, but not getting much traction nor over at DSL Report, Apple Forum. See Apple has seeded first Beta 10.13.5 - live in hope and die in disappear it will fix this? Another 13 Month out of bounds coding mishap?

Just spent 2 1/2 hrs Live Chat Apple. Uploaded Screen Shots of Console in Reg Mod and Safe Mod. Awaiting Call Back today 9:15 AM for followup.

The same error messages affect their own computers on 10.13.4 as per Entry Level Support

Will report back later after phone call

Callback from Apple done. Sent "Capture Data" to ftp results back to Apple and them to analyze. Now have to wait for results , if any.

No other suggestions from Apple on what is causing the signpost_notificationd SkyLight error messages in Console so just have to wait and see.

If anything more happens, will report back.

Just playing around in Activity Monitor.

CAUTION: not sure what the overall affect can be, so proceed at your own risk.

Tried to FORCE QUIT signpost_notificationsd. Since the daemon is Owned @ root it will not quit. Tried three times and still will not.

What I did find is that in Console the ongoing error messages disappeared / stopped.

Please explain"issue now closed"? Meaning the problem is reported but what is to come of it? Wait and hope?

Me, gave up on both late 2012 iMac and early 12' inch Retina MacBook both with Clean installs of 10.13.4. Have reverted to Regular Sierra 10.12.6. Think I may skip HS altogether for the very reason there have been so many Supplementals for 10.13 what with newer features plus APFS

sorry for late reply...issue closed by myself because Apple was not satisfied with by error logs and was pushing issue back at me,to re-format bug report.... so I closed it, seems 3 of my recent Bug reports were not up to their (Apple) specs, all were console errors...month13 out of bounds, signpost_notifcationSkyLight, andTouch Bar Ui errors Frustration on my part