The Cocoa built Emacs.app fails to launch and hangs with
high cpu usage when the physical memory is nearly full because of other
apps and the caching on OS X Yosemite.
After killing the hanging Emacs.app process and launching again, it
opens without any problem.
The problem happens only when launching with GUI. It never happens when
running emacs in the terminal with the -nw option.
I've got 2+2 GB physical ram in my Mac Book Pro 13'.
There are other complaints from Mac users describing the same
problem. eg.
https://github.com/Homebrew/homebrew/issues/25003https://groups.google.com/forum/#!topic/gnu.emacs.help/MGDN12Rf4QM