You can view the time and allocation profiling graph of your program graphically, using ghcprof. This is a new tool with GHC 4.08, and will eventually be the de-facto standard way of viewing GHC profiles
To run ghcprof, you need
uDraw(Graph)™ installed, which can be
obtained from uDraw(Graph). Install one of
distributions, and set your
UDG_HOME environment variable to point to the
ghcprof uses an XML-based profiling log
format, and you therefore need to run your program with a
-px. The file generated is
<prog>.prof. To see the
profile, run ghcprof like this:
$ ghcprof <prog>.prof
which should pop up a window showing the call-graph of your program in glorious detail. More information on using ghcprof can be found at The Cost-Centre Stack Profiling Tool for GHC.
 Actually this isn't true any more, we are working on a new tool for displaying heap profiles using Gtk+HS, so ghcprof may go away at some point in the future.