Installing for dependencies:
 libXaw                 i686   1.0.11-2.fc18              fedora          183 k
 nas-libs               i686   1.9.3-3.fc18               fedora           78 k
 pyliblzma              i686   0.5.3-7.fc18               fedora           46 k
 xorg-x11-apps          i686   7.7-1.fc18                 updates-testing 297 k

Transaction Summary
================================================================================
Install    1 Package  (+4 Dependent packages)
Upgrade  149 Packages

Total download size: 166 M
Is this ok [y/N]: y
Downloading Packages:
(1/154): audit-libs-2.2.2-2.fc18.i686.rpm                  |  74 kB   00:06
(2/154): NetworkManager-glib-0.9.7.0-12.git20121004.fc18.i | 305 kB   00:08
Traceback (most recent call last):
  File "/usr/bin/yum", line 29, in <module>
    yummain.user_main(sys.argv[1:], exit_code=True)
  File "/usr/share/yum-cli/yummain.py", line 319, in user_main
    errcode = main(args)
  File "/usr/share/yum-cli/yummain.py", line 227, in main
    return_code = base.doTransaction()
  File "/usr/share/yum-cli/cli.py", line 558, in doTransaction
    problems = self.downloadPkgs(downloadpkgs, callback_total=self.download_callback_total_cb)
  File "/usr/lib/python2.7/site-packages/yum/__init__.py", line 2307, in downloadPkgs
    urlgrabber.grabber.parallel_wait()
  File "/usr/lib/python2.7/site-packages/urlgrabber/grabber.py", line 2310, in parallel_wait
    start(opts, 1)
  File "/usr/lib/python2.7/site-packages/urlgrabber/grabber.py", line 2182, in start
    dl.start(opts)
  File "/usr/lib/python2.7/site-packages/urlgrabber/grabber.py", line 2112, in start
    dl = _ExternalDownloader()
  File "/usr/lib/python2.7/site-packages/urlgrabber/grabber.py", line 2035, in __init__
    stdout = subprocess.PIPE,
  File "/usr/lib/python2.7/subprocess.py", line 679, in __init__
    errread, errwrite)
  File "/usr/lib/python2.7/subprocess.py", line 1143, in _execute_child
    self.pid = os.fork()
OSError: [Errno 12] Cannot allocate memory
-bash-4.2#