------- Comment #21 from vmakarov at redhat dot com 2009-09-02 17:11 ------- I see. I though you compared '-fschedule-insns' and '-fschedule-insns -fsched-pressure'.
Your numbers shows the same as I reported for SPEC2000. The -fsched-pressure adds upto 3% compiler time (for power6) on x86 and x86_64 it is practically the same time (although -fsched-pressure does more job, it is compensated by smaller # of insns after RA). I did not analyzed your code but I think your code is quite specific and probably has a lot of parallelism which creates long ready and queue list. You could play with param max-pending-list-length to see will it help. -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=24319
