Re: [gentoo-dev] Re: ICC Profile

2008-07-19 Thread RĂ©mi Cardona
Duncan wrote: Has anyone done a study of -Os vs -O2 with gcc-4.3.x, Just a quick note while on the subject : -Os is known to break some packages. Although it has been a while since I've last had a full -Os system, there was a time when -Os was a _very_bad_idea_. That's why the Gnome Herd (

[gentoo-dev] Re: ICC Profile

2008-07-19 Thread Duncan
Richard Freeman <[EMAIL PROTECTED]> posted [EMAIL PROTECTED], excerpted below, on Fri, 18 Jul 2008 15:34:53 -0400: > Personally, I use -Os across the board when it doesn't break. As you > said I tend to be memory/IO bound, and optimizing for size helps with > both (swapping causes IO). I'd prob

Re: [gentoo-dev] Re: ICC Profile

2008-07-18 Thread Adam Stylinski
Perhaps we could write a script that compiles packages in portage with both ICC and GCC and runs them with different flags. I think there was an effort on the GCC side already to test flags with specific packages. We can then have the script run time on the applications doing work (again, that

Re: [gentoo-dev] Re: ICC Profile

2008-07-18 Thread Richard Freeman
Ciaran McCreesh wrote: How much of that is memory bound? Of the things that aren't, how many aren't written in assembly anyway? Of those things, what proportion of the runtime is spent in those areas? If you double the speed of something that takes up 2% of the overall execution time, you can't

Re: [gentoo-dev] Re: ICC Profile

2008-07-18 Thread Ciaran McCreesh
On Fri, 18 Jul 2008 15:34:53 -0400 Richard Freeman <[EMAIL PROTECTED]> wrote: > Ciaran McCreesh wrote: > > The more interesting question, then, is whether users run any > > non-trivial cpu-bound programs. We know the applied science types > > do, but they tend to be the ones who're doing clever thi

Re: [gentoo-dev] Re: ICC Profile

2008-07-18 Thread Richard Freeman
Ciaran McCreesh wrote: The more interesting question, then, is whether users run any non-trivial cpu-bound programs. We know the applied science types do, but they tend to be the ones who're doing clever things with icc anyway. What about normal users? I'm sure they do on some occasion if the

Re: [gentoo-dev] Re: ICC Profile

2008-07-18 Thread Adam Stylinski
He's also doing it on a core 2 duo. It would be interesting to compare this with some mildly legacy hardware (netburst pipelines) in order to see whether GCC does a comparable job. My guess would be no, seeing as netburst was extremely ugly and complicated, only intel would be able to write a

Re: [gentoo-dev] Re: ICC Profile

2008-07-18 Thread Ciaran McCreesh
On Fri, 18 Jul 2008 10:24:58 -0400 (EDT) Adam Stylinski <[EMAIL PROTECTED]> wrote: > GCC 4.3 is catching up, but they are no where near utilizing SSE4 or > SSE5 instructions. > > http://blog.alphagemini.org/2008/03/icc-vs-gcc-43.html > > He concludes that it's not worth pursuing, but I beg to d

[gentoo-dev] Re: ICC Profile

2008-07-18 Thread Nikos Chantziaras
Branko Badrljica wrote: BTW: Is ICC really worth the fuss ? I have checked around and reported that newest gcc-4.3 is able to to catch and sometimes even outperform icc ( not always, naturally). Big news seemed to be thatnew gcc si close and sometimes better than icc. Is it any truth to that

Re: [gentoo-dev] Re: ICC Profile

2008-07-18 Thread Adam Stylinski
GCC 4.3 is catching up, but they are no where near utilizing SSE4 or SSE5 instructions. http://blog.alphagemini.org/2008/03/icc-vs-gcc-43.html He concludes that it's not worth pursuing, but I beg to differ. Those are signifcant differences for a processor. -- gentoo-dev@lists.gentoo.org mai

Re: [gentoo-dev] Re: ICC Profile

2008-07-18 Thread Branko Badrljica
BTW: Is ICC really worth the fuss ? I have checked around and reported that newest gcc-4.3 is able to to catch and sometimes even outperform icc ( not always, naturally). Big news seemed to be thatnew gcc si close and sometimes better than icc. Is it any truth to that and if it is, what is the

Re: [gentoo-dev] Re: ICC Profile

2008-07-18 Thread Adam Stylinski
I actually know somebody working at intel, maybe he can get them more involved. -- gentoo-dev@lists.gentoo.org mailing list

[gentoo-dev] Re: ICC Profile

2008-07-18 Thread Nikos Chantziaras
Adam Stylinski wrote: The intel C Compiler (icc) has an ebuild for gentoo and the wiki has a script to integrate it with portage. I'm using ICC for programs where I have numbers about performance; for example, bzip2 is 30% faster here when compiled with ICC. However, one thing I don't like a