2

My recent upgrade to Yosemite (from Mavericks) took about 6 hours, nearly all of which time was used in processing the contents of /usr/local (e.g. TeX, etc.).

What is the upgrade process doing with these files that takes so long? Could I accelerate future updates by simply backing up these files, clearing the directory, and copying them manually after the update, or is the update process doing something critical with them?

Improve this question

1 Answer 1

Reset to default
2

The problem is only accute if you have a lot of files in /usr/local -- a few hundred files is not a problem. It needs to be many thousands of files. The reason, according to this post, is:

Part of the upgrade involves moving /usr/local out of the way. The process of moving those files back after the upgrade is done one file at a time and seems very slow.

He goes on to recommend removing anything from your Homebrew installs that isn't currently necessary with the brew remove; brew cleanup command pair. You can also move it aside, temporarily, naming it something like /usr/local.mine and then move it back after the update -- though this can make working with your Mac slightly problematic if you've, for example, switched your default shell for your account to be the Homebrew-supplied zsh or something like that.

Personally I opted to clean up my Homebrew installs. I also removed any Homebrew-installed daemons (MySQL, PostgreSQL and Redis) completely and shut them down. They're easy enough to get back after the installation is complete. In the end I had only a handful of Homebrew packages installed still that were very essential to me and the installation time wasn't too bad -- about 2 hours on an old iMac.

Of course, you can also wipe everything and just start again. First save everything you have installed:

brew list | sed s/\s+/\\n/g | tee my-brew-packages.txt

And now remove them all with:

cat ~/my-brew-packages.txt | xargs brew remove --force
brew cleanup --force

And to re-install things after you've updated:

cat ~/my-brew-packages.txt | xargs brew install
Improve this answer
4
  • So basically they're just being moved around, not examined or tweaked, so I could delete and restore myself to save time (next time)! TeX alone had thousands of files (it seems).
    – orome
    Oct 22, 2014 at 1:47
  • You can definitely remove it all and re-install after the upgrade. For the most part there should be no customizations in /usr/local itself for Homebrew packages. All that stuff lives in your home directory. I'll update the answer with some information on saving and restoring a Homebrew install.
    – Ian C.
    Oct 22, 2014 at 1:51
  • For me the issue is TeX (via MacTeX), Git, and Python (managed with pip).
    – orome
    Oct 22, 2014 at 1:53
  • See my updates. I'd just brew remove them and then brew install them when you're done. Don't forget to run brew cleanup after brew remove is done.
    – Ian C.
    Oct 22, 2014 at 1:56

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .