Hi folks, I just bought a pair of AMD64 systems for a work project, and I'm confused about the performance I'm getting from them. Both are identically configured Dell Dimension C521 systems, with Athlon 64 X2 3800+ CPUs and 1 GB RAM.
On one I installed using the Etch (4.0r0) i386 netinst CD, then upgraded to Lenny. This one's running linux-image-2.6.21-1-686. On the other I installed using the current (as of 2007-06-13) Lenny d-i amd64 snapshot netinst CD. This one's running linux-image-2.6.21-1-amd64. The one with the x86 userspace and 686 kernel is faster than the one with x86_64 userspace and amd64 kernel. The difference is consistently a few percent in favor of x86 over x86_64. My only benchmark is compiling our internal source tree (mostly running gcc, some g++, flex, bison, etc). We're using gcc-4.1 and g++-4.1. I've tried it with a cold disk cache and hot disk cache, in both cases x86 is faster than x86_64. I was expecting a win for 64 bit. What's going on here? -- Sebastian Kuzminsky "We're building a machine that will be proud of us." -- Danny Hillis, Thinking Machines Corporation, 1982 -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]
