1. top command:
- input the command:
top
- Output content display:
- content analysis:
PID: The ID of the process
USER: process owner
PR: The priority level of the process, the smaller the priority is to be executed
NI: Process Nice value, representing the priority value of this process
VIRT: virtual memory occupied by the process
RES: physical memory occupied by the process
SHR: Shared memory used by the process
S: The state of the process. S means sleep, R means running, Z means zombie
%CPU: Process occupied by CPU usage
%MEM: The percentage of physical memory and total memory used by the process
TIME+: The total CPU time occupied by the process after it is started, that is, the cumulative value of the CPU usage time
COMMAND: The name of the command that started the process
2. free command:
- Enter command categories:
free Display data in KB
free -m displays data in MB
free -h display data in GB
- Analysis of the output results:
total : total size of memory in the house
used : the size of the used memory
free : the amount of free memory
shared : total amount of memory shared by multiple processes
buff/cache : disk cache size
available : Available memory size, from the application's point of view: available = free + buff/cache .
3. cat /proc/meminfo command:
- Enter:
cat /proc/meminfo
- Output content analysis:
This is the easiest way to see RAM usage. This dynamically updated virtual file is actually a combination of many other memory-related tools, such as top, free, etc. listed above. It lists all the memory usage we want to know.
Process memory usage information can also be viewed through: /proc/<pid>/statm and /proc/<pid>/status.
4. ps command:
- How to enter content:
ps aux : display content by pid (default sorting)
ps aux --sort -rss : display content sorted by rss
- output:
5. vmstat command:
- input the command:
vmstat -s
- output:
