|Igor Schein on Thu, 08 Jan 2004 21:17:40 +0100|
[Date Prev] [Date Next] [Thread Prev] [Thread Next] [Date Index] [Thread Index]
|32bit vs 64bit comparison|
Hi, I compared 32bit vs 64bit performance of make dobench on 3 dual-arch platforms I have access to ( I haven't had access to SGI MIPS since 1998, and I've never had my hands on a PowerPC machine ) Here're the numbers: 32bit 64bit amd64-linux 612 372 sparc-sun 4784 1792 hppa-hpux 4458 6016 I used gcc-3.3.2, generic kernel, no gmp. 64bit is considerably faster on Opteron and Sun, but on HP 32bit is faster. 1 difference that comes to mind is that gcc on Opteron and Sun is dual-mode, where user can specify -m32 or -m64, while for HP you actually need 2 different build of gcc. It seems like a long shot though. Any other explanation? Any care to try the same thing on MIPS and PPC? Igor P.S. BTW, the 372 value for Opteron 64bit benchmark is a record, making it the fastest PARI machine in the world :) Not bad considering it's a generic kernel. However, with GMP enabled Alpha ev68 beats Opteron handily (see http://pari.math.u-bordeaux.fr/archives/pari-dev-0309/msg00028.html for my previous performance comparison). Not surprising, since GMP hasn't been optimized for Opteron yet.