[CentOS] How to determine 64 vs 32 bit processor

Wed Apr 10 14:22:49 UTC 2013
Robert Moskowitz <rgm at htt-consult.com>

On 04/10/2013 10:04 AM, Reindl Harald wrote:
> Am 10.04.2013 15:58, schrieb Robert Moskowitz:
>> I believe my new platform is suppose to be an x86_64. The order form
>> says 64 bit.
>> I booted Centos 6.3 i386 liveCD to check the system out before an install.
>> uname -i
>> reports i386
> no wonder, you boot a i386 kernel

OK.  I can 'llive' with this.  Just somewhere in some forgotten past I 
picked up that uname would still recognize that it was on a 64bit system 
even with the i386 kernel.

> simply boot a x86_64 liveCD
> hence i have not seen x86 systems since years
> Simply type "grep flags /proc/cpuinfo" and if you see lm
> you have a 64 bit CPU based system

> [root at rh:~]$ grep flags /proc/cpuinfo | grep lm
> flags           : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr
> sse sse2 ss ht tm pbe syscall nx rdtscp lm constant_tsc arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc
> aperfmperf eagerfpu pni pclmulqdq dtes64 monitor ds_cpl vmx smx est tm2 ssse3 cx16 xtpr pdcm pcid sse4_1 sse4_2
> x2apic popcnt tsc_deadline_timer aes xsave avx lahf_lm ida arat epb xsaveopt pln pts dtherm tpr_shadow vnmi
> flexpriority ept vpid