When I use -ipo-jobs4, hoping to speed up the link phase of my program, I get no speedup. top shows only one ifort process, requiring 100% of cpu on an 8 core machine with no other programs loading the machine. My admin group sees the same behavior. This behavior has been commented on before (http://software.intel.com/en-us/forums/showpost.php?p=60956), but with no reply.
What are limiting factors with splitting the IPO phase? How can I help the linker do its work faster?