[GUIDE] Potentially Improve macOS Boot Performance
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[GUIDE] Potentially Improve macOS Boot Performance  


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Joined: 5 years ago

With recent versions of macOS and the lack of quality control, I have come across a myriad of issues. Boot times are one of these. As a user/tester of multiple installations, things get annoying rather quickly for me, when boot takes much longer than it actually should for my primary work installation. Thus posting this little trick I seem to have stumbled on by shear chance. I have personally seen improvements of up to 3x for restarts and cold boots (if anyone cares).

First, a little primer on macOS booting. Think of this as a 5-stage process:

  1. System Power-On-Self-Test (POST) powers up and verifies necessary hardware
  2. EFI executes and captures boot disk (for which it has data)
  3. EFI initiates boot process - called the Early System Boot
  4. After early boot completes, the subsequent boot process is delegated to the OS
  5. OS completes the boot process, loading necessary kexts and graphics


There are a variety of factors that can affect boot speed at any stage in the above process. Cumulatively, this results in significantly slower boots (I consider 30-40s slow on a 2014 MBP, ideal speeds are at its slowest 17s on the same mac - helps a bunch if you reboot a lot like me). Such factors could be:

  1. EFI taking longer to find boot disk (Apple logo appearing on screen slower, usually immediate)
  2. Early Boot slower
  3. OS boot slower than normal (loading graphics kexts, etc.)


Before trying anything else, try going to System Preferences > Startup Disk, choose your boot disk, and restart from there. This may solve the issue entirely as it re-blesses the partition. If boot time hasn't improved, read on.


To potentially resolve these issues:

  1. Reset SMC - see how right here
  2. Reset NVRAM (optional) - see how right here
  3. Boot into Recovery (⌘ + R while powering on)
  4. Launch Disk Utility, and enable "Show All Devices" (or press ⌘ + 2)
  5. Repair your SSD Device (named APPLE SSD...)
  6. Repair your Boot Drive (takes longer)
  7. Quit Disk Utility and the Installer (⌘ + Q twice)
  8. In the prompt to reboot, choose startup disk as your Boot Drive and reboot
  9. If your SSD is NVMe, launch Terminal and type:

    [Please login to see this]

  10. After booting, go to System Preferences > Startup Disk, and select Boot Disk and restart again


This procedure improved my boot times significantly. Booting into Windows did not affect boot times. If you are using a custom NVMe SSD on an older mac, you may not see these improvements. If you upgraded from an HDD, you're gold. This works spectacularly well for default Apple SSDs installed correctly. Sometimes you may have to reset SMC again after performing the steps.


The improvements I observed were as follows:

  • Apple Logo appeared far sooner than before (quite obvious)
  • EFI delegated boot to OS far sooner than before
  • OS boot significantly quicker


Basically, improvements across the board. Without said improvements, boot times were 24-45s from the chime start. After changes, boot times reduces to 12-13s consistently. Of course, it worked for me, may not for you, or maybe you already have an optimal boot time. I feel delighted every time I boot. Feels like I'm back on Mavericks. It is worth noting that I am not using FileVault as of now. As you can see, I'm a bit too enthusiastic about shaving off seconds Smile

"Desultory reading is delightful, but to be beneficial, our reading must be carefully directed." — Seneca

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