Informações:

# ls /proc
1     20    2147  234  3    39   573  8          devices      kcore       mtrr           sysvipc
10    2048  2149  235  339  40   574  82         diskstats    keys        net            timer_list
11    2066  2171  237  340  435  576  9          dma          key-users   pagetypeinfo   timer_stats
12    2067  2210  238  347  450  577  905        driver       kmsg        partitions     tty
13    2068  2230  24   348  462  586  908        execdomains  kpagecount  sched_debug    uptime
1399  21    2231  240  361  5    59   acpi       fb           kpageflags  scsi           version
14    2108  2233  241  362  532  590  buddyinfo  filesystems  loadavg     self           vmallocinfo
15    2110  225   243  363  533  591  bus        fs           locks       slabinfo       vmstat
16    2111  227   25   364  534  603  cgroups    interrupts   mdstat      softirqs       zoneinfo
17    2112  228   26   365  535  605  cmdline    iomem        meminfo     stat
18    2113  229   27   366  541  621  consoles   ioports      misc        swaps
19    2114  231   28   367  570  622  cpuinfo    irq          modules     sys
2     2123  233   280  37   571  7    crypto     kallsyms     mounts      sysrq-trigger

Versão:

# uname -r
3.10.0-123.el7.x86_64

# cat /proc/cpuinfo 
processor	: 0
vendor_id	: GenuineIntel
cpu family	: 6
model		: 69
model name	: Intel(R) Core(TM) i7-4510U CPU @ 2.00GHz
stepping	: 1
cpu MHz		: 2594.153
cache size	: 4096 KB
physical id	: 0
siblings	: 1
core id		: 0
cpu cores	: 1
apicid		: 0
initial apicid	: 0
fpu		: yes
fpu_exception	: yes
cpuid level	: 13
wp		: yes
flags		: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 syscall nx rdtscp lm constant_tsc rep_good nopl xtopology nonstop_tsc pni pclmulqdq monitor ssse3 cx16 sse4_1 sse4_2 movbe popcnt aes xsave avx rdrand lahf_lm abm
bogomips	: 5188.30
clflush size	: 64
cache_alignment	: 64
address sizes	: 39 bits physical, 48 bits virtual
power management:

Estatistificas:

# yum install sysstat

# iostat -c
Linux 3.10.0-123.el7.x86_64 (localhost.localdomain) 	26-05-2016 	_x86_64_	(1 CPU)
 
avg-cpu:  %user   %nice %system %iowait  %steal   %idle
           0,03    0,00    0,09    0,34    0,00   99,54

# cat /proc/meminfo 
MemTotal:         711056 kB
MemFree:          426896 kB
MemAvailable:     444168 kB
Buffers:             764 kB
Cached:           101392 kB
SwapCached:            0 kB
Active:           149748 kB
Inactive:          80368 kB
Active(anon):     128140 kB
Inactive(anon):     5980 kB
Active(file):      21608 kB
Inactive(file):    74388 kB
Unevictable:           0 kB
Mlocked:               0 kB
SwapTotal:       1048572 kB
SwapFree:        1048572 kB
Dirty:                 0 kB
Writeback:             0 kB
AnonPages:        127992 kB
Mapped:            32048 kB
Shmem:              6160 kB
Slab:              27536 kB
SReclaimable:      15928 kB
SUnreclaim:        11608 kB
KernelStack:        1016 kB
PageTables:         7908 kB
NFS_Unstable:          0 kB
Bounce:                0 kB
WritebackTmp:          0 kB
CommitLimit:     1404100 kB
Committed_AS:     918576 kB
VmallocTotal:   34359738367 kB
VmallocUsed:        5692 kB
VmallocChunk:   34359730296 kB
HardwareCorrupted:     0 kB
AnonHugePages:     77824 kB
HugePages_Total:       0
HugePages_Free:        0
HugePages_Rsvd:        0
HugePages_Surp:        0
Hugepagesize:       2048 kB
DirectMap4k:       36800 kB
DirectMap2M:      700416 kB

Informação resumida:

# free -m
             total       used       free     shared    buffers     cached
Mem:           694        277        416          6          0         93
-/+ buffers/cache:        183        510
Swap:         1023          0       1023

Usando o vmstat:

# vmstat -a
procs -----------memory---------- ---swap-- -----io---- -system-- ------cpu-----
 r  b   swpd   free  inact active   si   so    bi    bo   in   cs us sy id wa st
 2  0      0 426896  80384 149788    0    0    34     3   18   60  0  0 100  0  0

# vmstat -s
       711056 K total memory
       284160 K used memory
       149764 K active memory
        80404 K inactive memory
       426896 K free memory
          764 K buffer memory
        95284 K swap cache
      1048572 K total swap
            0 K used swap
      1048572 K free swap
           53 non-nice user cpu ticks
            0 nice user cpu ticks
          210 system cpu ticks
       337072 idle cpu ticks
          927 IO-wait cpu ticks
            0 IRQ cpu ticks
           74 softirq cpu ticks
            0 stolen cpu ticks
       111487 pages paged in
        10658 pages paged out
            0 pages swapped in
            0 pages swapped out
        60909 interrupts
       201067 CPU context switches
   1464282163 boot time
         2240 forks

Estatistifica em megabytes

# vmstat -S M 1 5
procs -----------memory---------- ---swap-- -----io---- -system-- ------cpu-----
 r  b   swpd   free   buff  cache   si   so    bi    bo   in   cs us sy id wa st
 2  0      0    304      0    190    0    0    48    15   24   75  0  0 99  0  0
 0  0      0    304      0    190    0    0     0     0   43   92  0  0 100  0  0
 0  0      0    304      0    190    0    0     0     0   29   73  0  0 100  0  0
 0  0      0    304      0    190    0    0     0     0   35   80  0  0 100  0  0
 0  0      0    304      0    190    0    0     0     0   31   81  0  0 100  0  0