Try
lpr /usr/share/cups/data/testprint
Are you printing to a local or remote printer? What model? (This may depend on the size of the PDF and the printer language involved).
Read the posts by gsocker (post #10 and #12) in the following thread:
[ubuntu] PDF’s Very Slow to Print - Ubuntu Forums](http://ubuntuforums.org/showthread.php?t=1073942)