Linux Command Tool top command detailed __linux

Top is a dynamic display process, that is, the user can press the key to refresh the current state. If the command is executed at the foreground, it will monopolize the foreground until the user terminates the program. More precisely, the top command provides real-time state monitoring of the system's processors. It will show the CPU in the system the most "sensitive" List of tasks. This command can be used by the CPU. Memory usage and execution time to sort tasks; and the command's Many features can be set through interactive commands or in personal custom files.

Top-12:38:33 up, 23:15, 7 users, Load average:60.58, 61.14, 61.22

tasks:203 Total, running, 139 sleeping, 4 stopped, 0 zombie

Cpu (s): 27.0%us, 73.0%sy, 0.0%ni, 0.0%id, 0.0%wa, 0.0%hi, 0.0%si, 0.0%st

mem:1939780k Total, 1375280k used, 564500k free, 109680k buffers

swap:4401800k Total, 497456k used, 3904344k free, 848712k cached

PID USER PR NI virt RES SHR S%cpu%mem time+ COMMAND

4338 Oracle 0 627m 209m 207m R 0 11.0 297:14.76 Oracle

4267 Oracle 0 626m 144m 143m R 6 7.6 89:16.62 Oracle

3458 Oracle 0 672m 133m 124m R 0 7.1 1283:08 Oracle

3478 Oracle 0 672m 124m 115m R 0 6.6 1272:30 Oracle

3395 Oracle 0 672m 122m 113m R 0 6.5 1270:03 Oracle

3480 Oracle 0 672m 122m 109m R 8 6.4 1274:13 Oracle

3399 Oracle 0 672m 121m 110m R 0 6.4 1279:37 Oracle

4261 Oracle 0 634m 100m 99m R 0 5.3 86:13.90 Oracle

25737 Oracle 0 632m 81m 74m R 0 4.3 272:35.42 Oracle

7072 Oracle 0 626m 72m 71m R 0 3.8 6:35.68 Oracle

16073 Oracle 0 630m 68m 63m R 8 3.6 175:20.36 Oracle

16140 Oracle 0 630m 66m 60m R 0 3.5 175:13.42 Oracle

16122 Oracle 0 630m 66m 60m R 0 3.5 176:47.73 Oracle

786 Oracle 0 627m 63m 63m R 0 3.4 1:54.93 Oracle

4271 Oracle 0 627m 59m 58m R 8 3.1 86:09.64 Oracle

4273 Oracle 0 627m 57m 56m R 8 3.0 84:38.20 Oracle

22670 Oracle 0 626m 50m 49m R 0 2.7 84:55.82 Oracle one. Top Five Elements statistic information

The first five elements in the statistical information area are the statistical information of the whole system. 1. The first line is the task queue information

Results of execution with uptime command:

[Root@localhost ~]# Uptime

13:22:30 up 8 min, 4 users, Load average:0.14, 0.38, 0.25

Its contents are as follows:

12:38:33	Current time
Up 50days	System run time, format last: Min
1 user	Number of users currently logged in
Load average:0.06, 0.60, 0.48	System load, which is the average length of the task queue. Three values are 1 minutes, 5 minutes, and 15 minutes ago to the current average.

2. The second to third act process and CPU information

When you have more than one CPU, the content can be more than two lines. The contents are as follows:

tasks:29 Total	Total Processes
1 Running	Number of processes that are running
Sleeping	Number of processes to sleep
0 stopped	Number of processes stopped
0 Zombie	Number of zombie processes
Cpu (s): 0.3% US	Percentage of CPU consumed by user space
1.0% Sy	Kernel Footprint CPU percent
0.0% ni	Percentage of CPU in user process space that has changed priority
98.7% ID	Idle CPU percent
0.0% WA	Percentage of CPU time waiting for input output
0.0% hi
0.0% si

3. The 45th Act memory information.

The contents are as follows:

MEM:191272K Total	Total Physical Memory
173656k used	Total amount of physical memory used
17616k Free	Total Free Memory
22052k buffers	Amount of memory used as kernel cache
SWAP:192772K Total	Total Exchange Area
0k used	Total number of swap areas used
192772k Free	Total Free Swap Area
123988k Cached	The total number of buffered swap areas. The content in memory is swapped out to the swap area and then swapped into memory, but the used swap area has not been overwritten, which is the size of the swap area where the content already exists in memory . When the corresponding memory is swapped out again, you do not have to write to the swap area again.

two. Process Information The

Column name	Meaning
PID	Process ID
PPID	Parent process ID
Ruser	Real user name
UID	User ID for Process owner
User	User name for process owner
Group	Process Owner's group name
TTY	To start the terminal name of the process. Processes that are not started from the terminal are displayed as  ?
PR	Precedence
NI	Nice value. A negative value indicates a high priority, and a positive value indicates a low priority
P