For those of you using Homebrew and Homebrew installed PostgreSQL, here's a few notes on my Yosemite upgrade from over the weekend:
The installation process went smoothly right up until the end. With "3 minutes remaining" it appeared to stall. Be patient. In the background the installer is doing some weird copying routine of /usr/local. This took 4 hours on my machine. Hit Cmd-L to see the log of what's going on.
During the above mentioned copying routine of /usr/local, it seems to be skipping empty directories. Unfortunately PostgreSQL requires a few of these empty directories to be present to run properly. To fix this simply run:
mkdir -p /usr/local/var/postgres/{pg_tblspc,pg_twophase,pg_stat_tmp}/
See this StackOverflow post for more information.
Homebrew now depends on XCode 6.1 which was not in the app store when I upgraded. After you do all of your other updates, you'll need to download and install XCode manually from https://developer.apple.com/downloads/download.action?path=Developer_Tools/xcode_6.1/xcode_6.1.dmg
I did this over the weekend, and noticed that I had to reinstall pow to get it properly serving sites again.
To uninstall:
then to reinstall