From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ionut Georgescu Date: Fri, 24 Oct 2003 15:14:50 +0000 Subject: Itanium2@900MHz slower than alpha@666MHz ? Message-Id: List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-ia64@vger.kernel.org Hello, I am puzzled about the speed of a zx2000 workstation with a 900Mhz CPU. According to the SPECfp2000 benchmarks, this workstation should be about twice as fast as a DS10 alpha workstation and according to the fftw2 benchmarks at least 50% faster (double precision, real data, 256x256 FFT transforms). I ran the fftw2 benchmark myself and I could reproduce the data on fftw.org However, my program is about 40% slower on the zx2000 as on the alpha. It only does some Fourier transforms (fftw2, 256x256) and some matrix operations (sort of an inner product). Both fftw2 and the program have been compiled with ecc -O2 -ipo -limf. ecc is Version 7.1, Build 20030307. Both the alpha and the Itanium2 run Debian stable and kernel 2.4.20. Is there anything else I can do to improve performance ? I tried to some profiling (CFLAGS="-g -p -Ob0 -O0 -inline_debug_info"), but the report is missing the call-graph and a lot of other information, so that I can't trust the quality of those data. Right now I'm trying to dig my way through qprof and pfmon (for the moment qprof fails when QPROF_HW_EVENT is set). Thanks a lot, Ionut -- *************** * Ionut Georgescu * http://www.physik.tu-cottbus.de/~george/ * Registered Linux User #244479 * * "In Windows you can do everything Microsoft wants you to do; in Unix you * can do anything the computer is able to do."