今天查看linux服务器，想查看各个进程的占用率，就使用：
[qhkf@116share ~]$ top
PID USER PR NI VIRT RES SHR S %
cpu %MEM TIME+ COMMAND
29613 build 15 0 158m 7136 3720 S 2.0 0.1 0:00.27 svn
29609 build 15 0 158m 7132 3720 S 2.3 0.1 0:00.70 svn
29601 qhkf 15 0 12868 1260 820 R 0.3 0.0 0:00.09 top
29598 oracle 15 0 1935m 15m 13m S 0.0 0.2 0:00.00 oracle
29596 oracle 15 0 1936m 27m 24m S 0.0 0.3 0:00.03 oracle
29582 qhkf 15 0 102m 3420 2252 S 0.0 0.0 0:00.04 vim
29506 build 15 0 158m 7252 3724 S 2.3 0.1 0:03.76 svn
但是没有按照
内存排序，然后查了下，按一下shift + f 就可以出现排序的列
Current Sort Field: N for window 1:Def
Select sort field via field letter, type any other key to return
a: PID = Process Id shown due to screen width or your
b: PPID = Parent Process Pid field order, the '<' and '>' keys
c: RUSER = Real user name will be unavailable until a field
d: UID = User Id within viewable range is chosen.
e: USER = User Name
f: GROUP = Group Name Note2:
g: TTY = Controlling Tty Field sorting uses
internal values,
h: PR = Priority not those in column display. Thus,
i: NI = Nice value the TTY & WCHAN fields will violate
j: P = Last used cpu (SMP) strict ASCII collating sequence.
k: %CPU = CPU usage (shame on you if WCHAN is chosen)
l: TIME = CPU Time
m: TIME+ = CPU Time, hundredths
* N: %MEM = Memory usage (RES)
o: VIRT = Virtual Image (kb)
p: SWAP = Swapped size (kb)
q: RES = Resident size (kb)
r: CODE = Code size (kb)
s: DATA = Data+Stack size (kb)
t: SHR = Shared Mem size (kb)
u: nFLT = Page Fault count
v: nDRT = Dirty Pages count
w: S = Process Status
x: COMMAND = Command name/line
y: WCHAN = Sleeping in Function
z: Flags = Task Flags <sched.h>
然后就可以选择自己喜欢的排序方式啦，例如选择N，看看那几个进程占用的内存大，接下来就可以分析啦
PID USER PR NI VIRT RES SHR S %CPU%MEM TIME+ COMMAND
14101 oracle 15 0 1941m 613m 608m S 0.0 7.7 2:25.78 oracle
14095 oracle 15 0 1987m 521m 477m S 0.0 6.5 2:24.58 oracle
20477 oracle 15 0 1945m 483m 478m S 0.0 6.1 0:24.79 oracle
14522 oracle 15 0 1941m 427m 420m S 0.0 5.4 2:20.59 oracle
14105 oracle 15 0 1941m 268m 262m S 0.0 3.4 3:46.04 oracle
