Mastodawn

John Siracusa Sep 27, 2023

Still trying to track down this bug https://mastodon.social/@siracusa/110255326994000695

To review:

1. It happens only when more than one user is logged in.

2. It does not happen on a clean install of Sonoma—but it does happen on my actual install of Sonoma.

3. It happens even when the only two users logged in are two newly created user accounts.

4. No non-Apple KEXTs are installed.

Given all of this, I've been looking in /Library for culprits. Is there some other place I should be looking?

John Siracusa Sep 28, 2023

Important update to https://mastodon.social/@siracusa/110255326994000695

The bug *is* reproducible on a clean install of macOS 14.0 (23A344).

It was not reproducible in an earlier Sonoma beta, but that changed some time between then and the release version.

At least I can stop tearing third-party software out of my system now…

…but now it’s time to try removing some hardware…

(Reminder for Apple folks: this is FB12122106.)

John Siracusa Sep 28, 2023

I've re-filed this bug against Sonoma specifically (because some Apple folks tell me this is a useful thing to do). Please see FB13211706 for a newly summarized report with new spindumps, samples, a sysdiagnose, and a new demonstration video.

I'm looking for someone with access to a 2019 Mac Pro (preferably with a Radeon Pro Vega II GPU) to try to reproduce FB13211706 as demonstrated in https://youtu.be/5Aq2GZpKkLU

Has Apple tried to reproduce it internally? I don't know. I've had no response in the Feedback app since I filed my original report six months ago. So I'm looking for a someone who is willing to actually communicate with me to tell me if it's just my Mac or what.

FB13211706: Window dragging is laggy and jumpy when more than one user is logged in

YouTube

Oh, FFS…it's my mouse! My stupid Microsoft Precision Mouse that has already been replaced under warranty once! When I use my wife's mouse, it no longer happens.

My mouse is connected via a USB cable, and the issue reproduces on a fresh install of macOS Sonoma with zero third-party software installed. So it has to be a hardware issue with the mouse—a hardware issue that only manifests when more than one user is logged in and window dragging happens with other visible windows, which is wild!

The same mouse works fine when connected via Bluetooth. It’s only when connected via USB that the bug happens.

@siracusa write something to peg one CPU, and see if it reproduces more easily on BT? 🤔 Try connecting to the machine over Screen Sharing and if it repros there via a VNC cursor

@stroughtonsmith One CPU pegged at 100% with an infinite loop and everything's fine.

@siracusa new thought: does the problem scale with the number of logged in users? I only have one extra account here… Maybe it's a session-based event routing issue

@stroughtonsmith I tried it with four users logged in, and it seems about the same as with two, but it’s hard to tell.

@siracusa ok, so I was able to reproduce on an M1 MacBook Air with just any old USB RF mouse. The screen resolution has to be above a certain threshold to show it easily (but 2560x1440 was enough).

It did not reproduce with the Magic Trackpad over USB, so it must be something to do with mice specifically. This wasn't an expensive mouse with a high refresh rate, just a cheap mouse

TL;DR it's not you!

@stroughtonsmith What specific model of mouse are you using? My ancient USB Logitech MX300 doesn't reproduce it.

@siracusa hahaha I’m glad you asked, because it’s literally a no-brand mouse with generic internals 😂 Was the first mouse I could find on my shelf

@stroughtonsmith An “Acorn" clone of the original Macintosh mouse!?

@siracusa no longer available but it was a gift from Kevin Noki who did that amazing Macintosh II case for the Raspberry Pi https://www.youtube.com/watch?v=miN8sADrsgA

Macintosh Mouse - 3D Printed

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David Hall

@siracusa @stroughtonsmith I saw he posted a new video today. https://youtu.be/7N9oz4Ylzm4 Impressive.

3D Printed Apple Macintosh - The Brewintosh

YouTube