High CPU usage on 6.33.0

[litori]

AltTab 6.33.0 causes high cpu usage on AltTab and launchd process. Nonstop for 1 hour now. Killing AltTab gets rid of launchd cpu usage.

[metacodes]

@litori Could you share what apps you were using when this issue happened? I'm trying to reproduce this issue.

[litori]

I closed all my apps and just have activity monitor on and launchd, logd, and alttab will be the top 3 cpu usage hovering around 20 for launchd, 5 for logd, and 8 for alttab. Once I open discord and firefox without any websites, launchd will be at 55, alttab at 30, and logd at 27.

[panpietrek]

Same here with v. 6.33.0
Apps open are Firefox (v99), Activity Monitor and Signal Desktop 5.38. Activity Monitor show AltTab munching ~25% CPU.

EDIT: Happens even with FF alone and this bugreport as the only site open.
Another edit: Even FF alone with one empty tab immediately causes AltTab to spike the CPU to ~25%. Closing Firefox brings CPU usage down right away. No such behavior when using MS Edge alone.

[panpietrek]

launchd and logd's CPU usage goes up as well, presumably due to this spamming launchd.log file:

[litori]

The fact that it uses so much cpu without anything open besides activity monitor is already a problem. I've binned 6.33.0 for now as it is not usable.

[metacodes]

@litori @panpietrek I have located the problem and am working on it. See #1437 . You can use 6.31.0 before this issue is fixed.

[metacodes]

See PR #1484

[burdo3417]

Same problem. Also just firefox opened.
Macbook Pro M1 Pro
MacOS 12.3.1

[otandka]

For easier searching by log message keywords, here are the messages from "log show -last 1m" that are repeated every 150usec or so.

2022-04-14 10:30:57.116774-0700 0x635391   Default     0x0                  1      0    launchd: [gui/501 [100006]:] failed lookup: name = com.apple.axserver, handle = 92824, flags = 0x3, requestor = AltTab[88006], error = 3: No such process
2022-04-14 10:30:57.116861-0700 0x635391   Default     0x0                  1      0    launchd: [gui/501 [100006]:] could not find active service for lookup: pid = 84636, name = com.apple.axserver
2022-04-14 10:30:57.116868-0700 0x635391   Default     0x0                  1      0    launchd: [user/501:] could not find active service for lookup: pid = 84636, name = com.apple.axserver
2022-04-14 10:30:57.116872-0700 0x635391   Default     0x0                  1      0    launchd: [system:] could not find active service for lookup: pid = 84636, name = com.apple.axserver