Karabiner-NotificationWindow Occupying CPU Cycles

[asugerman]

macOS version: macOS 10.14.6
Karabiner version: Karabiner-Elements 12.6.0
Your Mac hardware: MacBook Pro
Your keyboard hardware: MacBook Pro

Computer is sluggish and when I check the Activity Monitor, the process "Karabiner-NotificationWindow" is generally in the 20-25% range, which seems like way too much. I don't remember seeing it occupy this much activity in the past and nothing comes close besides the WindowServer. Is this a new issue or has something changed recently? I recall updating to a new Karabiner just a few days ago.

Thanks,
-Adam

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[wongjustin99]

I'm having this issue as well, it happens even when I leave my computer idle for hours. I come back and hear the fans spin up because of this process. I'm using latest beta 12.8.4, but only because was trying this to fix the issue, was using latest GA before that.

[brentgreeff]

Same issue with 12.9.0. - 14-22% CPU usage which is ridiculous. I also noticed that there have been 792214 faults. I have the exact same issue where the fan comes on when the computer is idle.

Content from my log:

[2020-03-07 07:19:14.684] [info] [observer] registry_entry_id: 4295013745
[2020-03-07 07:19:14.684] [info] [observer] product: Apple Internal Keyboard / Trackpad
[2020-03-07 07:19:14.701] [info] [observer] vendor_id: 1452
[2020-03-07 07:19:14.701] [info] [observer] product_id: 630
[2020-03-07 07:19:14.701] [info] [observer] location_id: 0x1000000
[2020-03-07 07:19:14.701] [info] [observer] is_keyboard: false
[2020-03-07 07:19:14.701] [info] [observer] is_pointing_device: true
[2020-03-07 07:19:14.702] [info] [observer] rescan devices...
[2020-03-07 07:19:14.702] [info] [observer] matching device:
[2020-03-07 07:19:14.702] [info] [observer] registry_entry_id: 4295013738
[2020-03-07 07:19:14.702] [info] [observer] product: Apple Internal Keyboard / Trackpad
[2020-03-07 07:19:14.702] [info] [observer] vendor_id: 1452
[2020-03-07 07:19:14.702] [info] [observer] product_id: 630
[2020-03-07 07:19:14.702] [info] [observer] location_id: 0x1000000
[2020-03-07 07:19:14.702] [info] [observer] is_keyboard: true
[2020-03-07 07:19:14.702] [info] [observer] is_pointing_device: false
[2020-03-07 07:19:14.703] [info] [observer] rescan devices...
[2020-03-07 07:19:14.705] [info] [observer] Apple Internal Keyboard / Trackpad (device_id:4295013738) is observed.
[2020-03-07 07:19:14.726] [info] [observer] Apple Internal Keyboard / Trackpad (device_id:4295013745) is observed.
[2020-03-07 07:19:15.480] [info] [grabber] Apple Internal Keyboard / Trackpad (device_id:4295013738) is grabbed.
[2020-03-07 07:28:18.212] [info] [grabber] Apple Internal Keyboard / Trackpad (device_id:4295013738) is terminated.
[2020-03-07 07:28:18.242] [info] [grabber] Apple Internal Keyboard / Trackpad (device_id:4295013745) is terminated.
[2020-03-07 07:28:18.617] [info] [observer] device_id:4295013745 is terminated.
[2020-03-07 07:28:18.685] [info] [observer] device_id:4295013738 is terminated.
[2020-03-07 07:28:18.686] [info] [observer] rescan devices...
[2020-03-07 07:28:18.687] [info] [observer] rescan devices...
[2020-03-07 07:28:18.687] [info] [observer] matching device:
[2020-03-07 07:28:18.687] [info] [observer] registry_entry_id: 4295013807
[2020-03-07 07:28:18.687] [info] [observer] product: Apple Internal Keyboard / Trackpad
[2020-03-07 07:28:18.687] [info] [observer] vendor_id: 1452
[2020-03-07 07:28:18.687] [info] [observer] product_id: 630
[2020-03-07 07:28:18.687] [info] [observer] location_id: 0x1000000
[2020-03-07 07:28:18.687] [info] [observer] is_keyboard: false
[2020-03-07 07:28:18.687] [info] [observer] is_pointing_device: true
[2020-03-07 07:28:18.687] [info] [observer] rescan devices...
[2020-03-07 07:28:18.688] [info] [observer] matching device:
[2020-03-07 07:28:18.688] [info] [observer] registry_entry_id: 4295013800
[2020-03-07 07:28:18.688] [info] [observer] product: Apple Internal Keyboard / Trackpad
[2020-03-07 07:28:18.688] [info] [observer] vendor_id: 1452
[2020-03-07 07:28:18.688] [info] [observer] product_id: 630
[2020-03-07 07:28:18.688] [info] [observer] location_id: 0x1000000
[2020-03-07 07:28:18.688] [info] [observer] is_keyboard: true
[2020-03-07 07:28:18.688] [info] [observer] is_pointing_device: false
[2020-03-07 07:28:18.688] [info] [observer] rescan devices...
[2020-03-07 07:28:18.690] [info] [observer] Apple Internal Keyboard / Trackpad (device_id:4295013800) is observed.
[2020-03-07 07:28:18.717] [info] [observer] Apple Internal Keyboard / Trackpad (device_id:4295013807) is observed.
[2020-03-07 07:28:19.220] [info] [grabber] Apple Internal Keyboard / Trackpad (device_id:4295013800) is grabbed.
[2020-03-07 07:37:23.253] [info] [grabber] Apple Internal Keyboard / Trackpad (device_id:4295013800) is terminated.
[2020-03-07 07:37:23.272] [info] [grabber] Apple Internal Keyboard / Trackpad (device_id:4295013807) is terminated.
[2020-03-07 07:37:23.803] [info] [observer] device_id:4295013800 is terminated.
[2020-03-07 07:37:23.975] [info] [observer] device_id:4295013807 is terminated.
[2020-03-07 07:37:23.978] [info] [observer] rescan devices...
[2020-03-07 07:37:23.978] [info] [observer] rescan devices...
[2020-03-07 07:37:23.978] [info] [observer] matching device:
[2020-03-07 07:37:23.978] [info] [observer] registry_entry_id: 4295013869
[2020-03-07 07:37:23.978] [info] [observer] product: Apple Internal Keyboard / Trackpad
[2020-03-07 07:37:23.978] [info] [observer] vendor_id: 1452
[2020-03-07 07:37:23.978] [info] [observer] product_id: 630
[2020-03-07 07:37:23.983] [info] [observer] location_id: 0x1000000
[2020-03-07 07:37:23.983] [info] [observer] is_keyboard: false
[2020-03-07 07:37:23.983] [info] [observer] is_pointing_device: true
[2020-03-07 07:37:23.984] [info] [observer] rescan devices...
[2020-03-07 07:37:23.984] [info] [observer] matching device:
[2020-03-07 07:37:23.984] [info] [observer] registry_entry_id: 4295013862
[2020-03-07 07:37:23.985] [info] [observer] product: Apple Internal Keyboard / Trackpad
[2020-03-07 07:37:23.985] [info] [observer] vendor_id: 1452
[2020-03-07 07:37:23.985] [info] [observer] product_id: 630
[2020-03-07 07:37:23.985] [info] [observer] location_id: 0x1000000
[2020-03-07 07:37:23.985] [info] [observer] is_keyboard: true
[2020-03-07 07:37:23.985] [info] [observer] is_pointing_device: false
[2020-03-07 07:37:23.985] [info] [observer] rescan devices...
[2020-03-07 07:37:24.056] [info] [observer] Apple Internal Keyboard / Trackpad (device_id:4295013862) is observed.
[2020-03-07 07:37:24.087] [info] [observer] Apple Internal Keyboard / Trackpad (device_id:4295013869) is observed.
[2020-03-07 07:37:24.290] [info] [grabber] Apple Internal Keyboard / Trackpad (device_id:4295013862) is grabbed.
[2020-03-07 07:46:28.335] [info] [grabber] Apple Internal Keyboard / Trackpad (device_id:4295013862) is ungrabbed.
[2020-03-07 07:46:28.340] [info] [grabber] Apple Internal Keyboard / Trackpad (device_id:4295013869) is terminated.
[2020-03-07 07:46:28.347] [info] [grabber] Apple Internal Keyboard / Trackpad (device_id:4295013862) is terminated.
[2020-03-07 07:46:28.511] [info] [observer] device_id:4295013862 is terminated.
[2020-03-07 07:46:28.513] [info] [observer] device_id:4295013869 is terminated.
[2020-03-07 07:46:28.634] [info] [observer] rescan devices...
[2020-03-07 07:46:28.634] [info] [observer] rescan devices...
[2020-03-07 07:46:28.661] [info] [observer] matching device:
[2020-03-07 07:46:28.687] [info] [observer] registry_entry_id: 4295013931
[2020-03-07 07:46:28.687] [info] [observer] product: Apple Internal Keyboard / Trackpad
[2020-03-07 07:46:28.689] [info] [observer] vendor_id: 1452
[2020-03-07 07:46:28.689] [info] [observer] product_id: 630
[2020-03-07 07:46:28.689] [info] [observer] location_id: 0x1000000
[2020-03-07 07:46:28.689] [info] [observer] is_keyboard: true
[2020-03-07 07:46:28.690] [info] [observer] is_pointing_device: false
[2020-03-07 07:46:28.693] [info] [observer] rescan devices...
[2020-03-07 07:46:28.693] [info] [observer] matching device:
[2020-03-07 07:46:28.693] [info] [observer] registry_entry_id: 4295013938
[2020-03-07 07:46:28.694] [info] [observer] product: Apple Internal Keyboard / Trackpad
[2020-03-07 07:46:28.694] [info] [observer] vendor_id: 1452
[2020-03-07 07:46:28.694] [info] [observer] product_id: 630
[2020-03-07 07:46:28.694] [info] [observer] location_id: 0x1000000
[2020-03-07 07:46:28.694] [info] [observer] is_keyboard: false
[2020-03-07 07:46:28.694] [info] [observer] is_pointing_device: true
[2020-03-07 07:46:28.829] [info] [observer] rescan devices...
[2020-03-07 07:46:29.087] [info] [observer] Apple Internal Keyboard / Trackpad (device_id:4295013931) is observed.
[2020-03-07 07:46:29.107] [info] [observer] Apple Internal Keyboard / Trackpad (device_id:4295013938) is observed.
[2020-03-07 07:46:29.348] [info] [grabber] Apple Internal Keyboard / Trackpad (device_id:4295013931) is grabbed.
[2020-03-07 07:55:32.286] [info] [grabber] Apple Internal Keyboard / Trackpad (device_id:4295013931) is ungrabbed.
[2020-03-07 07:55:32.297] [info] [grabber] Apple Internal Keyboard / Trackpad (device_id:4295013938) is terminated.
[2020-03-07 07:55:32.313] [info] [grabber] Apple Internal Keyboard / Trackpad (device_id:4295013931) is terminated.
[2020-03-07 07:55:32.543] [info] [observer] device_id:4295013938 is terminated.
[2020-03-07 07:55:32.558] [info] [observer] device_id:4295013931 is terminated.
[2020-03-07 07:55:32.558] [info] [observer] rescan devices...
[2020-03-07 07:55:32.558] [info] [observer] rescan devices...
[2020-03-07 07:55:32.558] [info] [observer] matching device:
[2020-03-07 07:55:32.558] [info] [observer] registry_entry_id: 4295014000
[2020-03-07 07:55:32.558] [info] [observer] product: Apple Internal Keyboard / Trackpad
[2020-03-07 07:55:32.558] [info] [observer] vendor_id: 1452
[2020-03-07 07:55:32.558] [info] [observer] product_id: 630
[2020-03-07 07:55:32.559] [info] [observer] location_id: 0x1000000
[2020-03-07 07:55:32.559] [info] [observer] is_keyboard: false
[2020-03-07 07:55:32.559] [info] [observer] is_pointing_device: true
[2020-03-07 07:55:32.559] [info] [observer] rescan devices...
[2020-03-07 07:55:32.559] [info] [observer] matching device:
[2020-03-07 07:55:32.559] [info] [observer] registry_entry_id: 4295013993
[2020-03-07 07:55:32.559] [info] [observer] product: Apple Internal Keyboard / Trackpad
[2020-03-07 07:55:32.559] [info] [observer] vendor_id: 1452
[2020-03-07 07:55:32.559] [info] [observer] product_id: 630
[2020-03-07 07:55:32.559] [info] [observer] location_id: 0x1000000
[2020-03-07 07:55:32.559] [info] [observer] is_keyboard: true
[2020-03-07 07:55:32.559] [info] [observer] is_pointing_device: false
[2020-03-07 07:55:32.567] [info] [observer] rescan devices...
[2020-03-07 07:55:32.627] [info] [observer] Apple Internal Keyboard / Trackpad (device_id:4295013993) is observed.
[2020-03-07 07:55:32.648] [info] [observer] Apple Internal Keyboard / Trackpad (device_id:4295014000) is observed.
[2020-03-07 07:55:33.303] [info] [grabber] Apple Internal Keyboard / Trackpad (device_id:4295013993) is grabbed.
[2020-03-07 08:04:37.237] [info] [grabber] Apple Internal Keyboard / Trackpad (device_id:4295013993) is terminated.
[2020-03-07 08:04:37.263] [info] [grabber] Apple Internal Keyboard / Trackpad (device_id:4295014000) is terminated.
[2020-03-07 08:04:37.784] [info] [observer] device_id:4295014000 is terminated.
[2020-03-07 08:04:37.787] [info] [observer] rescan devices...
[2020-03-07 08:04:37.787] [info] [observer] device_id:4295013993 is terminated.
[2020-03-07 08:04:37.798] [info] [observer] rescan devices...
[2020-03-07 08:04:37.798] [info] [observer] matching device:
[2020-03-07 08:04:37.798] [info] [observer] registry_entry_id: 4295014062
[2020-03-07 08:04:37.798] [info] [observer] product: Apple Internal Keyboard / Trackpad
[2020-03-07 08:04:37.804] [info] [observer] vendor_id: 1452
[2020-03-07 08:04:37.804] [info] [observer] product_id: 630
[2020-03-07 08:04:37.804] [info] [observer] location_id: 0x1000000
[2020-03-07 08:04:37.804] [info] [observer] is_keyboard: false
[2020-03-07 08:04:37.804] [info] [observer] is_pointing_device: true
[2020-03-07 08:04:37.805] [info] [observer] rescan devices...
[2020-03-07 08:04:37.806] [info] [observer] matching device:
[2020-03-07 08:04:37.806] [info] [observer] registry_entry_id: 4295014055
[2020-03-07 08:04:37.806] [info] [observer] product: Apple Internal Keyboard / Trackpad
[2020-03-07 08:04:37.806] [info] [observer] vendor_id: 1452
[2020-03-07 08:04:37.806] [info] [observer] product_id: 630
[2020-03-07 08:04:37.806] [info] [observer] location_id: 0x1000000
[2020-03-07 08:04:37.806] [info] [observer] is_keyboard: true
[2020-03-07 08:04:37.806] [info] [observer] is_pointing_device: false
[2020-03-07 08:04:37.807] [info] [observer] rescan devices...
[2020-03-07 08:04:37.833] [info] [observer] Apple Internal Keyboard / Trackpad (device_id:4295014055) is observed.
[2020-03-07 08:04:37.843] [info] [observer] Apple Internal Keyboard / Trackpad (device_id:4295014062) is observed.
[2020-03-07 08:04:38.222] [info] [grabber] Apple Internal Keyboard / Trackpad (device_id:4295014055) is grabbed.
[2020-03-07 08:05:47.424] [info] [grabber] Apple Internal Keyboard / Trackpad (device_id:4295014062) is terminated.
[2020-03-07 08:05:47.432] [info] [grabber] Apple Internal Keyboard / Trackpad (device_id:4295014055) is terminated.
[2020-03-07 08:05:48.290] [info] [observer] device_id:4295014055 is terminated.
[2020-03-07 08:05:48.439] [warning] [grabber] Apple Internal Keyboard / Trackpad (device_id:4295014117) is not observed yet. Please wait for a while.
[2020-03-07 08:05:48.460] [info] [observer] device_id:4295014062 is terminated.
[2020-03-07 08:05:48.535] [info] [observer] rescan devices...
[2020-03-07 08:05:48.535] [info] [observer] rescan devices...
[2020-03-07 08:05:48.535] [info] [observer] matching device:
[2020-03-07 08:05:48.535] [info] [observer] registry_entry_id: 4295014117
[2020-03-07 08:05:48.535] [info] [observer] product: Apple Internal Keyboard / Trackpad
[2020-03-07 08:05:48.535] [info] [observer] vendor_id: 1452
[2020-03-07 08:05:48.535] [info] [observer] product_id: 630
[2020-03-07 08:05:48.536] [info] [observer] location_id: 0x1000000
[2020-03-07 08:05:48.536] [info] [observer] is_keyboard: true
[2020-03-07 08:05:48.536] [info] [observer] is_pointing_device: false
[2020-03-07 08:05:48.537] [info] [observer] rescan devices...
[2020-03-07 08:05:48.537] [info] [observer] matching device:
[2020-03-07 08:05:48.537] [info] [observer] registry_entry_id: 4295014124
[2020-03-07 08:05:48.537] [info] [observer] product: Apple Internal Keyboard / Trackpad
[2020-03-07 08:05:48.537] [info] [observer] vendor_id: 1452
[2020-03-07 08:05:48.537] [info] [observer] product_id: 630
[2020-03-07 08:05:48.537] [info] [observer] location_id: 0x1000000
[2020-03-07 08:05:48.537] [info] [observer] is_keyboard: false
[2020-03-07 08:05:48.537] [info] [observer] is_pointing_device: true
[2020-03-07 08:05:48.537] [info] [observer] rescan devices...
[2020-03-07 08:05:48.587] [info] [observer] Apple Internal Keyboard / Trackpad (device_id:4295014117) is observed.
[2020-03-07 08:05:48.590] [info] [grabber] Apple Internal Keyboard / Trackpad (device_id:4295014117) is grabbed.
[2020-03-07 08:05:48.682] [info] [observer] Apple Internal Keyboard / Trackpad (device_id:4295014124) is observed.
[2020-03-07 08:39:16.968] [info] [observer] matching device:
[2020-03-07 08:39:16.968] [info] [observer] registry_entry_id: 4295014419
[2020-03-07 08:39:16.968] [info] [observer] product: USB Optical Mouse
[2020-03-07 08:39:16.968] [info] [observer] vendor_id: 7119
[2020-03-07 08:39:16.968] [info] [observer] product_id: 5
[2020-03-07 08:39:16.968] [info] [observer] location_id: 0x14320000
[2020-03-07 08:39:16.968] [info] [observer] is_keyboard: false
[2020-03-07 08:39:16.968] [info] [observer] is_pointing_device: true
[2020-03-07 08:39:16.985] [info] [observer] rescan devices...
[2020-03-07 08:39:17.165] [info] [observer] USB Optical Mouse (device_id:4295014419) is observed.
[2020-03-07 11:14:08.381] [info] [grabber] USB Optical Mouse (device_id:4295014419) is terminated.
[2020-03-07 11:14:08.387] [info] [observer] device_id:4295014419 is terminated.
[2020-03-07 11:14:08.390] [info] [observer] rescan devices...
[2020-03-07 17:37:55.430] [info] [observer] matching device:
[2020-03-07 17:37:55.431] [info] [observer] registry_entry_id: 4295019895
[2020-03-07 17:37:55.431] [info] [observer] product: USB Optical Mouse
[2020-03-07 17:37:55.431] [info] [observer] vendor_id: 7119
[2020-03-07 17:37:55.431] [info] [observer] product_id: 5
[2020-03-07 17:37:55.431] [info] [observer] location_id: 0x14320000
[2020-03-07 17:37:55.431] [info] [observer] is_keyboard: false
[2020-03-07 17:37:55.431] [info] [observer] is_pointing_device: true
[2020-03-07 17:37:55.433] [info] [observer] rescan devices...
[2020-03-07 17:37:55.434] [info] [observer] USB Optical Mouse (device_id:4295019895) is observed.
[2020-03-07 19:37:16.403] [error] [grabber] console_user_server_client error: Connection reset by peer
[2020-03-07 19:37:16.403] [info] [grabber] console_user_server_client is closed. (uid:501)
[2020-03-07 19:37:16.420] [info] [grabber] event_tap_monitor terminated
[2020-03-07 19:37:16.517] [info] [observer] device_id:4294976368 is terminated.
[2020-03-07 19:37:16.523] [info] [grabber] virtual_hid_device_client is closed.
[2020-03-07 19:37:16.524] [info] [grabber] device_grabber is stopped.
[2020-03-07 19:37:16.547] [info] [observer] rescan devices...
[2020-03-07 19:40:26.529] [info] [console_user_server] version 12.9.0
[2020-03-07 19:40:26.673] [info] [console_user_server] receiver is initialized
[2020-03-07 19:40:26.675] [info] [console_user_server] receiver: bound
[2020-03-07 19:40:26.675] [info] [console_user_server] grabber_client is started.
[2020-03-07 19:40:26.675] [info] [console_user_server] grabber_client is connected.
[2020-03-07 19:40:26.909] [info] [grabber] karabiner_console_user_server is connected.
[2020-03-07 19:40:26.909] [info] [console_user_server] Load /Users/brentgreeff/.config/karabiner/karabiner.json...
[2020-03-07 19:40:26.910] [info] [grabber] console_user_server_client is connected. (uid:501)
[2020-03-07 19:40:26.911] [info] [grabber] device_grabber is started.
[2020-03-07 19:40:26.923] [info] [console_user_server] core_configuration is updated.
[2020-03-07 19:40:26.928] [info] [grabber] event_tap_monitor initialized
[2020-03-07 19:40:26.929] [info] [grabber] virtual_hid_device_client is started.
[2020-03-07 19:40:26.929] [info] [grabber] Load /Users/brentgreeff/.config/karabiner/karabiner.json...
[2020-03-07 19:40:26.931] [info] [grabber] core_configuration is updated.
[2020-03-07 19:40:26.932] [info] [grabber] virtual_hid_device_client is opened.
[2020-03-07 19:40:26.933] [info] [grabber] virtual_hid_device_client_ is connected
[2020-03-07 19:40:26.933] [info] [grabber] initialize_virtual_hid_keyboard
[2020-03-07 19:40:26.933] [info] [grabber] country_code:0
[2020-03-07 19:40:26.934] [info] [grabber] initialize_virtual_hid_keyboard
[2020-03-07 19:40:26.934] [info] [grabber] country_code:0
[2020-03-07 19:40:26.942] [info] [observer] matching device:
[2020-03-07 19:40:26.942] [info] [observer] registry_entry_id: 4295022081
[2020-03-07 19:40:26.942] [info] [observer] manufacturer: pqrs.org
[2020-03-07 19:40:26.942] [info] [observer] product: Karabiner VirtualHIDKeyboard
[2020-03-07 19:40:26.942] [info] [observer] vendor_id: 5824
[2020-03-07 19:40:26.942] [info] [observer] product_id: 10203
[2020-03-07 19:40:26.942] [info] [observer] location_id: 0x0
[2020-03-07 19:40:26.942] [info] [observer] serial_number: pqrs.org:org_pqrs_driver_Karabiner_VirtualHIDDevice_VirtualHIDKeyboard_v061000
[2020-03-07 19:40:26.942] [info] [observer] is_keyboard: true
[2020-03-07 19:40:26.942] [info] [observer] is_pointing_device: false
[2020-03-07 19:40:26.948] [info] [observer] rescan devices...
[2020-03-07 19:40:26.981] [info] [observer] Karabiner VirtualHIDKeyboard (device_id:4295022081) is observed.
[2020-03-07 19:40:27.048] [info] [console_user_server] Check for updates...
[2020-03-07 19:40:27.175] [info] [grabber] system_preferences is updated.
[2020-03-07 19:40:27.949] [info] [grabber] Apple Internal Keyboard / Trackpad (device_id:4295014117) is grabbed.

[nissenbenyitskhak]

I am having this same or similar issue with karabiner_observer and karabiner_grabber using way too much CPU time. In fact, I have 2 each of karabiner_grabber and karabiner_observer processes. One karabiner_observer has used 2:21:21.77 of CPU time (about 2.5 HOURS of CPU time) and one karabiner_grabber has used 3:13:24.44 of CPU time (over 3 HOURS of CPU time). Activity monitor screen is attached. That's 5 ½ hours of CPU time for a keyboard mapper!

I am using MacOS Catalina 10.15.5 on a 15" 2018 MacBook Pro with 32GB of memory.

[brentgreeff]

This is happening every day now - around 5pm.
If I kill Karabiner-NotificationWindow it doesnt help

• SystemUIServer is using 15-20% and killing that process doesnt help
• it just restarts by itself & goes back to work spinning in a circle.
  I either need to reboot, or I just discovered I can open Karabiner & restart - that gets rid of SystemUIServer and the fans calm down eventually.

What is Karabiner trying to notify me about?

[brentgreeff]

Every day at 5:30pm German time (Central European Standard Time) - there goes my fans.
I tried to reload today but that didn't work - had to restart my computer.
How can I debug this - its infuriating.

[brentgreeff]

Restarting my machine didnt help.
Quiting & restarting Karabiner didnt help.

• had to uninstall

[tyteen4a03]

Still an issue - it happens for me when I plug in an external drive for Time Machine backups.

[hieast]

I'm having this issue as well. I come back after leaving my computer idle for tens of minutes and see this process occupying 90+% CPU usage. Kill this process worked but it will happen again some time.

macOS version: macOS 11.4 (20F71)
Karabiner version: Karabiner-Elements 13.5.0
Your Mac hardware: MacBook Pro
Your keyboard hardware: MacBook Pro

[amirmohsen-am]

I'm having the same issue in macOS 12.0.1 on an m1 macbook pro

[brianherbert]

I woke my M1 Max from sleep to find Karabiner-NotificationWindow occupying 100% CPU along with WindowServer. Machine was barely usable (extremely sluggish). Force quitting the process just now solved the problem.

[gholmes829]

Using macOS 12.01 on 2021 M1 MacBook Pro with min hardware specs. I am not currently noticing excessive cpu use at 1.1%.

It does look like Karabiner-NotificationWindow is using excessive memory however. I killed and restarted karabiner after noticing it using 800+ MB. After killing and restarting it, I actually got prompted to update karabiner. I did so and proceeded to observe it using 100 MB which seems more reasonable. I don't know if this is important, but killing this process caused my computer to freeze which then forced me to the login screen some 15 seconds later.

I'm checking again this evening and its currently using 500+ MB which seems high again. It doesn't seem normal to have the service jump from using 100 MB to 800+ MB for one key remapping, but maybe I'm mistaken.