tag:blogger.com,1999:blog-4212234230338648875.post1089069914412752161..comments2024-03-27T20:43:05.862-07:00Comments on The Eternal Universe: Compilers Can Make A Big Difference.Joseph Smidthttp://www.blogger.com/profile/02583891162785742138noreply@blogger.comBlogger2125tag:blogger.com,1999:blog-4212234230338648875.post-56216847336733934192010-01-31T16:21:01.822-08:002010-01-31T16:21:01.822-08:00Stan,
Thanks for the points, and you're p...Stan,<br /><br /> Thanks for the points, and you're probably right. This is a new Intel machine with new Intel compilers. Furthermore the version of gcc is years older than the hardware it's on.<br /><br />It probably is something to do with optimizations the Intel compiler is doing that gcc isn't/can't/Joseph Smidthttps://www.blogger.com/profile/02583891162785742138noreply@blogger.comtag:blogger.com,1999:blog-4212234230338648875.post-68462044287650205252010-01-31T14:46:11.658-08:002010-01-31T14:46:11.658-08:00It could simply be that your new compiler uses dif...It could simply be that your new compiler uses different default settings for optimizations. Take a close look at all the command line arguments and play around with them. The C compilers generate native code (vs. interpreted or byte code languages) and can be fine tuned to your particular hardware. <br /><br />The intel compiler running on intel hardware probably has default settings to optimize that combination. gcc runs on so many platforms they don't make those assumptions by default.<br /><br />Have you used a profiler? If you're worried about tuning for speed a profiler can be invaluable. Often times our human assumptions about bottlenecks are just wrong.Stannoreply@blogger.com