Severe Battery Drain and overheating on MacBook Pro M5 after upgrading to macOS 27 Golden Gate

It is possible there are processes running in the background that are using significant resources. Check Activity Monitor, CPU tab (sort by % CPU) and Memory tab (sort by Memory) to see what's running hard.

Activity Monitor User Guide for Mac - Apple Support

Confirm that you have sufficient free space on your internal storage. Seems unlikely with a new Mac, but if you migrated from a prior Mac then you may be low on space. Another user reported rapid battery drain and it turned out there was only 8 GB free on that user's 512 GB storage.

The absolute minimum is ~20-25 GB free space, and as a rule of thumb you should aim to have 15-20% of your total internal storage as free space. Terminology is important here – free space is not the same thing as available space. The one that matters is Free space, but what macOS shows in most places is Available space. Available space includes both free space and ‘purgeable’ space, the latter comprises system caches, snapshots and other data that macOS can delete if it decides more free space is needed. However, there is no way the user can force those data to be purged.

The place to check how much Free space you have is in Disk Utility (in Applications > Utilities), by selecting the main container disk below the drive itself (you may need to select View menu > Show all devices to see it). For example, on my M4 MacBook Pro, the Storage settings pane and Get Info on the internal drive show 1.24 TB of Available space, whereas Disk Utility shows there is 1.15 TB of actual Free space, 90 GB less than ‘available’. Although 90 GB is a small fraction of my 2 TB internal storage, that would not be the case with 256 GB or 512 GB of internal storage.

Note that you can also see the Free space in the System Report (System Settings > General > About > System Report button, at the bottom > Storage). 

Some steps to take to safely free up space:

Free up storage space on Mac - Apple Support

Optimize storage space on your Mac - Apple Support

How to free up ‘System Data’ and other st… - Apple Community

If nothing in the above reveals an obvious culprit, then appropriate troubleshooting steps are Safe Mode and creating a new user account to test. 

See if the problem is present when you boot in safe mode. That process performs some system cleanup and clears caches, and also disables 3rd party extensions that may cause problems.

Start up your Mac in safe mode - Apple Support

If that does not correct the issue, test in a new user account. A newly-created user account will have all settings at default, and if the issue does not occur in that new account then it provides guidance on what may need to be changed to correct the issue.

Add a user or group on Mac - Apple Support

Once the testing is complete, the new account can easily be deleted.

Delete a user or group on Mac – Apple Support

If you have 3rd party ‘protection’ software installed, that may be the problem. That includes:

Cleaners (software claiming to automatically free up space)

Optimizers (software claiming to make your Mac run faster)

Antivirus software

VPN software (unless provided by a school/employer to enable access to internal resources from a remote location)

Such 3rd party system ‘helpers’, ‘cleaners’ and ‘protectors’ do more harm than good. In fact, such products are completely unnecessary for macOS and the only ‘good’ (if you want to call it that) they do is to put money in the developers’ pockets. Cleaners and protectors cause compatibility issues, often after macOS updates. Commercial VPNs claim to hide your browsing activity from websites, and while that may be true those VPN providers just sell your browsing data to others. For the user, all of these types of software offer only harm…and if that is limited to harm to your bank account, then count yourself lucky. If you have installed such software, follow the developer’s instructions to completely uninstall it (note that some developers fail to provide instructions and their software installs can be pervasive, meaning the only way to truly remove it is to erase your Mac, reinstall macOS then restore your user files from a backup).

It might help to download and run EtreCheck, written by a long-time forum member. The free version is fine. Post the full report using the Additional Text button. No personal information is revealed. 

Personally, I have been running macOS 27 Golden Gate on my 16" M4 Pro MBP since the upgrade came out, and have had no issues with battery life (which was a good thing, since I was at a conference for a couple of days running on battery for ~10 hours, and had 50% battery left at the end of each day).

Continued...

So at this point, what I am trying to understand is whether the Mac is technically entering sleep but waking repeatedly in the background, which could explain both the battery drain and why the computer sometimes feels warm even though I am not actively using it.

Use the "pmset" command & filter I provided to see what the system is doing. It will tell you whether the system is asleep or awake during the time you expect it to be asleep.

Keep in mind that closing the lid may not put the laptop to sleep....it is more of a suggestion. You can try using the "Sleep" option on the Apple menu to manually trigger sleep mode....even then it may take a bit of time for the system to go to sleep.

Keep in mind that any active programs, even background processes may keep the system awake. I cannot count how many times over the years I go to restart the computer and the system would get a spinning wheel during the shutdown process, or where it could take 5 minutes to complete the shutdown process, or it could even be aborted by some active process. Sleep is not really much different.

Also keep in mind that pressing any key or even the Trackpad can cause the laptop to wake up or power on. Connecting & disconnecting devices can do so as well.

If you have external devices connected to the laptop.....perhaps they are keeping it awake or are causing some of the drain if they require the laptop to keep them powered even in a low power state.

In my experience, the main reasons for a laptop to wake up are due to cloud file syncing services, apps checking for updates, and Bluetooth devices (I believe multiple people reported their Logitech mouse was the problem). You can easily turn off WiFi and/or Bluetooth to see if it can help narrow down your search.

Anti-virus software, cleaning & optimizer apps, and third party security software are notorious for causing all sorts of problems because they all interfere with the normal operation of macOS. If you have any of these apps installed, then uninstall them by following their developer's instructions.

This is also why I’m having a hard time attributing the problem simply to my development software. The same applications and essentially the same workload were present before macOS 27, but this behavior only appeared after the upgrade.

Make sure all third party software are completely up to date and those versions are fully compatible with macOS 27.

If you have experience interpreting the pmset sleep/wake logs, I would really appreciate your thoughts on the repeated DarkWake activity. If there are any additional commands, logs, or specific sections of an EtreCheck report that you think would be useful, I’d be happy to run them and post the results.

Thanks again for your help and for taking the time to provide such a detailed response.

An EtreCheck report would help identify some third party software issues as well as providing summaries of some of the system logs, as well as some performance metrics. It is one of the easiest troubleshooting options to see whether any of the commonly known issues are involved here.

As another respected forum contributor mentions.....laptops are battery capable devices, but they work best when connected to a power adapter. So use a power adapter whenever you are near an electrical outlet.

FYI, I was testing an M1 MBAir laptop where I let the system idle without sleeping...only the display would turn off to conserve battery power (a couple apps were open, but had no real activity). The laptop went about three days like this where the power drain was only about 0.05 amps with a couple of minutes where it consumed at maximum about 0.5 amps (I had my software monitoring the battery). For a similar laptop which actually went to sleep, I have seen some last for a couple of months. Even completely powered off the same laptop may only hold a charge for at most six months.

Also, most DarkWakes will not consume any battery power because the system is not fully enabled at that point, and most DarkWakes lasting less than a minute (many just a few seconds). On my own personal laptop connected to power on DarkWake was 15 minutes which in my experience is unusual (I didn't even bother to see what it was).

Also note, that Apple Intelligence cannot be disabled on macOS 27 like it could be on Tahoe. Since this Apple Intelligence is completely new....no one here has any idea how it actually works & what effect it has on the system & power consumption (we know it consumes about 35GB of storage for the local model). Just pointing it out since that is one of the biggest changes.

Actually I am facing this exact same issue too.

Yesterday I noticed that my Mac battery decreased by 20 percent overnight (normally I dont notice it since I keep it plugged in).

Then I went to my activities and saw my Mac was active whole night and I was afraid that someone might have used it without me knowing. But, then I asked Gemini about it and Gemini gave a prompt to paste in terminal and after doing so, I saw countless wake requests and those were especially because of some Apple Intelligence stuff. But, then I restarted my Mac as guided my Gemini and nothing changed, my Macs battery performance is still not quite great as it was in macOS 26. I suppose the new update is causing it since there should be absolutely no other reason for this to happen. Hope thus gets fixed soon.Meanwhile, u could try some suggestions gemini provided me with.

Turn off Summarized Notifications: Navigate to System Settings > Apple

Intelligence & Siri and turn off Summarize Notifications (or completely toggle the feature off temporarily).

Hard-kill Sleep Network Checks: Go to System Settings > Battery > Options... and set Wake for network access to Never.

Check for Rogue Login Extensions: Go to System Settings > General > Logintems & Extensions. Scroll down to the "Allow in Background" section and disable everything except your absolute essential apps to stop unoptimized software from triggering wakes.

Let me know if it works for you.

Since updating to macOS 27, my MacBook Pro M5 repeatedly wakes from sleep into DarkWake every ~15 minutes. The logs show frequent wifibt SMC.OutboxNotEmpty events, sometimes lasting 20+ seconds. This still happens with Wi-Fi and Bluetooth disabled. The Battery graph also sometimes shows activity while the Mac is closed and asleep.

This happens throughout the night and also during the day while the Mac is not being used.

I checked the system logs with pmset -g log and found a very large number of repeated events such as:

DarkWake from Deep Idle [CDNP] :
due to smc.sysState.Wake(0x70070000)
wifibt SMC.OutboxNotEmpty/
Using BATT

That's annoying me so much. Apple fix this please

mikee87 wrote:

More importantly, the severe battery drain is happening when I am not running that workload at all.

In one of my recent tests, I left the Mac sleeping and unplugged. It went from approximately 100% battery to 1% over roughly 16 hours, while it was supposed to be sleeping.

"While it was supposed to be sleeping" is a very important item to note.

But whatever is causing is likely also occurring while you are actively using the laptop (at least any background processes that not waiting for system down time to run).

I then started looking at pmset and the sleep/wake logs.

Running:

pmset -g assertions

did not•  show a permanent application or system process preventing sleep. In the results I saw:

PreventSystemSleep = 0

• BackgroundTask = 0

• NetworkClientActive = 0

•

There were some temporary assertions, including one from coreaudiod associated with the built-in speakers, as well as Handoff/network-related activity and a kernel MAGICWAKE assertion associated with IOSkywalkNetworkBSDClient, but nothing that appeared to be a permanent sleep blocker.

macOS tends to create a lot of temporary assertions. I've found they don't really help to figure out the issue.

When I looked deeper into the sleep/wake history, however, things became more interesting.

The logs showed a fairly large number of sleep/wake events, including 225 Sleep/Wakes since boot, and one sleep cycle showed 7 Dark Wakes• .

Yes, macOS can wake up every few minutes for a few seconds. I also see wakes every 10/15/20 minutes as well, and will occasionally see an hour or two sleep session (less often).

I have found the following Terminal command can filter out a lot of the noise to see when the largest battery drain occurs (spaces in the filter are critical):

pmset -g log  |  grep  -E  'Sleep  |Wake  '

This allows me to focus on the wake cycle where the largest drain is occurring. Whether the wake reason is clear is another matter as that may require you to capture the main system log for the period between wake & the following sleep period. However, it will contain tens of thousands of entries (perhaps hundreds or thousands of entries per second) with many of the entries repeating. The main system log will contain lots of scary errors & warnings with most of them being irrelevant. Good luck combing through that mess to identify the likely culprit. Here is a template of the command to capture the system logs for that time period (replace the date & time accordingly)....best to save the output to a text file as well:

log show  --start "2026-09-21 14:01:00"  --end "2026-09-21 14:12:00"

Make sure to use valid time values especially for the start time, or you may not capture anything if there is no actual entry for that starting time stamp (should not be a problem if you use the time shown in the 'pmset' wake time). Good luck trying to find anything in that haystack. And don't go crazy since the macOS system logs are no longer meant for troubleshooting system issues.

For my organization's managed Macs where I was trying to identify the source of intense system utilization during normal use, there was no single culprit even with a single laptop.

Welcome!

I get the impression that GG allows your computer to be usable while still doing some serious housekeeping. I did not see battery drain when updating, but my M4 Pro Macbook Pro was on the charger during and after the update (my standard procedure). For now you might try leaving it on the charger.

Of course, with any concern like this, your should let Apple know using this: Feedback - macOS - Apple

Apple does not participate in these user-to-user forums. The feedback link will place your concern before an Apple employee.

mikee87 wrote:

I’m wondering whether there could be something specific to the M5/M5 Pro platform, a particular system service, or some power-management behavior triggered by the upgrade.

It's certainly possible. When I first got my 16" M4 Pro MBP, I noticed that the resolution I typically use with my 21:9 ultrawide display (3480 x 1620) was not available. It was and remained available on Sequoia and Tahoe on my other Mac, a 16" M1 Pro MBP, but not on the M4 Pro. Then with the macOS 27 Golden Gate upgrade, the 3480 x 1620 became an option on the M4 Pro Mac as well. So clearly, there can be machine/processor specific issues in macOS. Your battery drain may well be one of them.

Bugs should be reported to Apple here:

Feedback - macOS - Apple

I have been force quitting apps to make sure nothing else drains the battery but the drainage is just off a cliff. Iused to get two full days with eight hours plus screen on time, just between 20 and 80 percent on my Macbook pro M4 pro 16". Now I get 6 in total, if that.

[Edited by Moderator]

mikee87 wrote:

Hi Everyone

I'm so thankful for your support, you helped me so much!

The solution was very simple, I had to uninstall some applications that were deprecated for this macOS version, and also other that will be deprecated for the next macOS release.

So after uninstall these applications, the Mac returns to normal.

Thanks Gus!!!

Thanks for the update. Third party apps tend to be a very common problem especially after a major OS upgrade.

Got the same Issue, with a 3 months old MacBook Air M5, running the latest 27.2 Golden Gate Update, it got worse from the first Update to this. And now all my Apple Devices are facing this issue, from researching other forums and reddit, it's quite clear, that this is a general Problems, and should be fixed ASAP. In the time I wrote this I lost 2%...

param163 wrote:

I have been force quitting apps to make sure nothing else drains the battery but the drainage is just off a cliff. Iused to get two full days with eight hours plus screen on time, just between 20 and 80 percent on my Macbook pro M4 pro 16". Now I get 6 in total, if that.

https://discussions.apple.com/content/attachment/f7964859-a862-409b-9802-4b74623fbe8a

[Edited by Moderator]

Force Quitting apps can corrupt things and cause data loss due to unsaved documents. If you cannot Quit an app normally, then that is where the real problem is since all apps should be able to properly terminate when Quitting them normally.

If you mean you are trying to quit background apps & processes, then the solution to that is to change those app's configuration settings, and if that is not possible, then uninstall those troublesome apps.

Your screenshot shows the Display is on during the period of battery drain so that means your computer is not asleep. A computer that is not asleep will drain the battery faster than one which is asleep.

Either connect the laptop to power when able, or fully power off the laptop. Both options will solve the problem.

I am facing the exact same issue on my M5 Air, right after installing MacOS27. I can attribute it to applications I use the most, but that's not how you fix these issues. There is no additional app I have started using upon installing the new OS and my battery drains in 4-5 hours of use. Earlier (just until last week) it easily used to last for more than 10-12 hours. Apple should fix these issues before releasing such uncooked operating systems. What have they been doing with months of beta testings? It's atrocious!

I'm seeing this same issue on my 2024 Air (M3) after updating to Golden Gate. I'm currently on 27.0.1. I used to never have any issues and this is now the second time its completely drained itself while not even using it.