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User profile for user: olaf911
olaf911 Author
User level: Level 1
0 points

iMac keeps waking up about every 2 hours

Hello together,

since upgrading from Mavericks to Yosemite my iMac (2011) wakes from sleep about every 2 hours. This is particularly annoying since the iMac is located in my sleeping room. 😟

What I did do:

I unchecked the Energy Saving option for wakeup in case of network access, so network access should(!) not wake the iMac

I reset NVRAM

I reset SMC

I repaired file access permissions


Anyway, the iMac drives me crazy by refusing to keep sleeping. Is there any help out there for me? Had the same problem when I upgraded to Mavericks, btw.. The fix came in form of a OS-patch from Apple. *SIGH*

iMac (27-inch Mid 2011), OS X Yosemite (10.10)

Posted on Oct 29, 2014 12:40 PM

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18 replies
User profile for user: Linc Davis
Linc Davis
User level: Level 10
209,535 points

Oct 29, 2014 5:23 PM in response to olaf911

These instructions must be carried out as an administrator. If you have only one user account, you are the administrator.

This procedure is a diagnostic test. It makes no changes to your data.

Please triple-click anywhere in the line below on this page to select it:

syslog -k Sender kernel -k Message CSeq wake | awk '/:/{$4=""; print}' | pbcopy

Copy the selected text to the Clipboard by pressing the key combination command-C.

Launch the built-in Terminal application in any of the following ways:

☞ Enter the first few letters of its name into a Spotlight search. Select it in the results (it should be at the top.)

☞ In the Finder, select Go ▹ Utilities from the menu bar, or press the key combination shift-command-U. The application is in the folder that opens.

☞ Open LaunchPad. Click Utilities, then Terminal in the icon grid.

Paste into the Terminal window by pressing the key combination command-V. I've tested these instructions only with the Safari web browser. If you use another browser, you may have to press the return key after pasting.

Wait for a new line ending in a dollar sign ($) to appear below what you entered.

The output of the command will be automatically copied to the Clipboard. If the command produced no output, the Clipboard will be empty. Paste into a reply to this message.

The Terminal window doesn't show the output. Please don't copy anything from there.

If any personal information appears in the output, anonymize before posting, but don’t remove the context.

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User profile for user: olaf911
olaf911 Author
User level: Level 1
0 points

Oct 30, 2014 11:16 AM in response to Linc Davis

Thank you very much for your quick response. Unfortunately I was unable to reply as quick as you have. So here we go:


Oct 24 21:31:10 kernel[0] <Notice>: Wake reason: RTC (Alarm)

Oct 24 21:31:10 kernel[0] <Notice>: AppleThunderboltGenericHAL::earlyWake - complete - took 1 milliseconds

Oct 24 23:20:02 kernel[0] <Notice>: Wake reason: RTC (Alarm)

Oct 24 23:20:02 kernel[0] <Notice>: AppleThunderboltGenericHAL::earlyWake - complete - took 1 milliseconds

Oct 25 01:08:58 kernel[0] <Notice>: Wake reason: RTC (Alarm)

Oct 25 01:08:58 kernel[0] <Notice>: AppleThunderboltGenericHAL::earlyWake - complete - took 1 milliseconds

Oct 25 01:09:57 kernel[0] <Notice>: Wake reason: RTC (Alarm)

Oct 25 02:57:54 kernel[0] <Notice>: AppleThunderboltGenericHAL::earlyWake - complete - took 1 milliseconds

Oct 25 04:46:46 kernel[0] <Notice>: Wake reason: RTC (Alarm)

Oct 25 04:46:46 kernel[0] <Notice>: AppleThunderboltGenericHAL::earlyWake - complete - took 1 milliseconds

Oct 25 04:48:22 kernel[0] <Notice>: Wake reason: EHC2

Oct 25 04:48:22 kernel[0] <Notice>: The USB device HubDevice (Port 1 of Hub at 0xfa000000) may have caused a wake by issuing a remote wakeup (2)

Oct 25 04:48:22 kernel[0] <Notice>: AppleThunderboltGenericHAL::earlyWake - complete - took 1 milliseconds

Oct 25 04:48:22 kernel[0] <Notice>: The USB device Keyboard Hub (Port 2 of Hub at 0xfa100000) may have caused a wake by issuing a remote wakeup (3)

Oct 25 04:48:22 kernel[0] <Notice>: The USB device Apple Keyboard (Port 2 of Hub at 0xfa120000) may have caused a wake by issuing a remote wakeup (3)

Oct 25 04:48:22 kernel[0] <Notice>: full wake promotion (reason 1) 146 ms


This is the output you told me to generate. I am no specialist concerning Macs, so could you please tell me what to make of it?

I am not very proud to admit that I am a computer scientist myself, but the Mac is simply my workhorse, and I had no real reason until now to make me familiar with its internal workings. That is exactly the reason I bought it for. Now things seem to change however...


Btw, there is no peripheral attached to the Thunderbolt port. I have a Fritz!Box which might call out on WLAN, and there is an Apple TV also, but the settings should let the iMac ignore their calls.


And I don't want to switch off Multicast, if you want to suggest so... 😉

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User profile for user: olaf911
olaf911 Author
User level: Level 1
0 points

Oct 30, 2014 1:31 PM in response to Linc Davis

Hmmm...

I am slightly irritated. There are 2 Thunderbolt ports, but both are empty. There are USB ports at the iMac, which are occupied (external drives, mouse, scanner, ...). How can USB devices be attached to an Thunderbolt port, or better said, Thunderbolt display? The display itself is part of the whole computer in this case, as I am sure you are aware of. So I MUST have something misunderstood.

Do you mean one or more of those USB devices attached to the appropriate USB ports can wake the iMac?


(The error messages are indeed a few days old, because at the moment I am forced to shut down the iMac completely if I want to enjoy a good nights sleep.)

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User profile for user: olaf911
olaf911 Author
User level: Level 1
0 points

Oct 30, 2014 1:44 PM in response to William Lloyd

Got it. If so, why didn't they do it with Mavericks? I changed nothing when upgrading to Yosemite.

But this is a very valuable hint. I will detach all peripherals and see if that helps. Then I will reattach one at a time to find the one causing the trouble, if so.


To be honest, I am afraid this will not help. I suspect the iMac will keep waking up with no peripherals at all, except the USB keyboard, which must remain attached of course. However this will work out, I will post the results of my tests here. Maybe they can be helpful for other users with sleepless nights.


Thank you so far. Stay tuned... 😉

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User profile for user: olaf911
olaf911 Author
User level: Level 1
0 points

Oct 31, 2014 11:11 AM in response to olaf911

It is as I feared: I shut down the iMac, unplugged all USB devices and then started the iMac. Then I put it to sleep, but it kept waking up nearly every 2 hours:


Oct 31 17:01:41 kernel[0] <Notice>: Wake reason: RTC (Alarm)

Oct 31 17:01:41 kernel[0] <Notice>: AppleThunderboltGenericHAL::earlyWake - complete - took 1 milliseconds

Oct 31 18:50:33 kernel[0] <Notice>: Wake reason: RTC (Alarm)

Oct 31 18:50:33 kernel[0] <Notice>: AppleThunderboltGenericHAL::earlyWake - complete - took 1 milliseconds


I would be grateful for any suggestions what can be done about it...

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User profile for user: olaf911
olaf911 Author
User level: Level 1
0 points

Nov 2, 2014 2:29 AM in response to Linc Davis

I have tested without any USB devices attached to the display at all. Only plugs were the DLAN-cable internet connection and Apple's USB keyboard. WLAN is switched off. The behavior persists. 😟


In the meantime I contacted Apple support and followed their advice. That is what I did:

  • Emptied /Library/Caches
  • Emptied ~/Library/Caches
  • Emptied /System/Library/Caches
  • Removed ~/Library/LauchAgents (and moved it back later after it had no effect)
  • Tested whether the problem occurs in Safe Mode (is that the english word for starting the system with Shift key pressed?). It does.


No luck at all. So I am stuck. Now I would be even more grateful for anything I could do about it. 😢

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User profile for user: Linc Davis
Linc Davis
User level: Level 10
209,535 points

Nov 2, 2014 8:55 AM in response to olaf911

Test after each of the following steps that you haven’t already tried:

Step 1

Take all the steps suggested in this support article. That's the starting point for any further effort to solve the problem. Skipping any of those steps may mean that the problem won't be solved. Note that, as stated in the article, the computer will not sleep if some sharing services are enabled.

Step 2

From the menu bar, select

 ▹ System Preferences ▹ Accessibility ▹ Speakable Items: Off

Step 3

Select

 ▹ System Preferences ▹ Bluetooth ▹ Advanced...

and uncheck both boxes marked

Open Bluetooth Setup Assistant at startup if...

Step 4

Reset the SMC.

Step 5

Disconnect all wired peripherals and test. If you use a wired keyboard and/or mouse, use different ones. You must rule out the wired keyboard and mouse as possible causes of the problem.

Step 6

Start up in safe mode and log in to the account with the problem. You must hold down the shift key twice: once when you turn on the computer, and again when you log in.

Note: If FileVault is enabled in OS X 10.9 or earlier, or if a firmware password is set, or if the startup volume is a software RAID, you can’t do this. Ask for further instructions.

The login screen appears even if you usually log in automatically. You must know your login password in order to log in. If you’ve forgotten the password, you will need to reset it before you begin.

Safe mode is much slower to start and run than normal. Don’t launch any applications at first. If sleep still doesn’t work properly, back up all data and reinstall the OS. After that, if you still have the issue, make a “Genius” appointment at an Apple Store to have the machine tested.

If sleep now works as expected, go on to the next step.

Step 7

Still in safe mode, launch the usual set of applications that are running when you have the problem, including your login items, one at a time, testing after each one. Some applications may not work; skip them. You might be able to identify the cause of the problem this way.

Step 8

If sleep is still working after you’ve launched all the usual applications, restart as usual (not in safe mode) and test again. If sleep still works, you’re done, at least for the moment.

If you still have the sleep issue after restarting out of safe mode, post again.

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User profile for user: olaf911
olaf911 Author
User level: Level 1
0 points

Nov 4, 2014 8:19 AM in response to olaf911

I tried everything except a clean install. After all, the iMac should save me time, not consume it. Right?


Anyway, I am not alone, and it seems to be a bug in Yosemite.

In short:

There is a new DNS service in Yosemite, which does not recognize that it should keep sleeping. The appropriate switch from Mavericks is missing in the actual version.

Solution: Either install the service from Mavericks, but then multicast will not work anymore.

Or install some tool to switch off the new DNS service when the iMac is put to sleep, and switch in back on when you wake the beast. 😉

Or wait until Apple wakes up and fixes the bug. That is what I will do.


Here you can find out more about it and in more detail:


http://www.insanelymac.com/forum/topic/300072-wake-reason-rtc-alarm-how-to-deact ivate/page-6


Lesson learned:

After installing new versions of Apples OSes without any hesitation for a long time, from now on I will be waiting for some time. iOS 8 bit me too. Apple is not what it used to be anymore, it seems. 😢

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User profile for user: marelven
marelven
User level: Level 1
4 points

Nov 6, 2014 7:46 AM in response to olaf911

Agreed!

Since Apple switched to yearly releases, new OS X releases are getting really buggy. From now one, I'll wait until the 10.X.1 is out before installing a new version. I've been burnt too many times. 😠


I've got the same problem with my Mac. Unfortunately, I've been unable to find a better solution than to disable the discoveryd service

http://osquestions.com/osx-ios/151568/mac-wakes-up-from-sleep-every-two-hours-on -mac-os-x-yosemite

I didn't have time to test it, though. I'll give it a try tonight...

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iMac keeps waking up about every 2 hours

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