This was a question I was wondering for quite some time. All the things I read about this pointed to a positive answer: I have a Xeon CPU and all Xeon CPUs since second quarter 2004 support EM64T.
But I wanted something more reliable, like a
cat /proc/cpuinfo flag. And I finally found a post that gave my some hints about detecting EMT64 from the cpuinfo flags. It describes the
lm flag as "long mode", having the 64bit extensions, but it talks of those in AMD context.
Now the question for all: if I have a dual Xeon processor, is it worth it running CentOS with EM64T extensions or should I just run normal i386 version?