Messages on High Sierra not loading / delays new messages

Number:rdar://34832079 Date Originated:10/05/2017
Status:Open Resolved:
Product:macOS+SDK (Messages) Product Version:17A365
Classification:Serious Bug Reproducible:Sometimes
Since I installed High Sierra on my Mac, Messages has been very unreliable. When a friend sends me a message I receive it immediately on my iPhone, but on the Mac it sometimes appears with a delay of up to 20 minutes.

Steps to Reproduce:
1. Use iMessage on your Mac and iPhone
2. The bug usually occurs when Messages on the Mac has not been used in a while, but is open in the background.

Expected Results:
Messages on the Mac should immediately receive new messages as they arrive.

Actual Results:
Messages gets new messages delayed.
I can speed up the process by "waking up" Messages by sending a message. Me and my friend agreed to send a "." to each other when Messages hangs.

I created two sysdiagnoses (sysdiagnose Message, not just sysdiagnose). One while Messages was sitting idle, dreaming and not reloading Messages, while the chat continued on the iPhone and another sysdiagnose after I sent the "." message to wake it up.

macOS High Sierra 10.13 (17A365)

rMBP early 2015


same issue

Using a 2016 13" macbook pro touch bar. Old messages start arriving as new notifications in piles when waking the laptop from sleep. When using the macbook and receiving messages very often they don't come through or come through with a long delay (minutes) on macOS while they do on the iPhone / Apple Watch as normal.

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