如何知道linux服务器CPU是多少位的， CPU有几个是几核？
1. 查看CPU是多少位？
    # grep flag /proc/cpuinfo  如果发现cpu特性有lm , ia64 或者amd64， 就表示这个CPU是64位的
    也可以安装lshw这个rpm包或者tarball源码， 执行可以看到cpu的bitwise这一项， 64表示64位的cpu

2. 查看该服务器有多少个CPU， CPU是几核的？
    # grep processor | wc -l 可以确定这个服务的CPU个数 * 核数
    # grep physical



Understanding /proc/cpuinfo
Example:
$ uname -r
2.6.18-8.el5
How many physical processors are there?
$ grep 'physical id' /proc/cpuinfo | sort | uniq | wc -l
2
How many virtual processors are there?
$ grep ^processor /proc/cpuinfo | wc -l
4
Are the processors dual-core (or multi-core)?
$ grep 'cpu cores' /proc/cpuinfo
cpu cores       : 2
cpu cores       : 2
cpu cores       : 2
cpu cores       : 2
"2" indicates the two physical processors are dual-core, resulting in 4 virtual processors.
If "1" was returned, the two physical processors are single-core. If the processors are single-core, and the number of virtual processors is greater than the number of physical processors, the CPUs are using hyper-threading. Hyper-threading is supported if ht is present in the CPU flags and you are using an SMP kernel.
Are the processors 64-bit?
A 64-bit processor will have lm ("long mode") in the flags section of cpuinfo. A 32-bit processor will not.
e.g.,
flags           : fpu vme de pse tsc msr pae mce cx8 apic mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt lm 3dnowext 3dnow pni cx16 lahf_lm cmp_legacy svm cr8legacy ts fid vid ttp tm stc
What do the CPU flags mean?
The CPU flags are briefly described in the kernel header file cpufeature.h


附： 查看操作系统是多少位？
1. 最直接的， ls / 看下/目录下是不是有/lib64这个目录
2. getconf LONG_BIT  看输出