TOP command
This is the process monitoring information output by the top command under a Linux system. Here are the meanings of the columns:
top - 09:52:15: The current time.
up 27 min: The time the system has been running.
2 users: There are currently 2 users logged into the system.
load average: 0.97, 0.41, 0.21: The average load value of the system in the past 1 minute, 5 minutes and 15 minutes.
Next is the task list:
Tasks: There are 205 processes in total.
running: There are 3 processes running.
sleeping: There are 202 processes sleeping.
stopped: No processes are stopped.
zombie: No zombie process (Zombie Process).
Then the CPU usage:
%Cpu(s): Indicates the usage percentage of various CPU times.
us: user space ratio.
sy: Kernel space ratio.
ni: The user process space occupancy rate (nice value) used to adjust the process priority.
id: Indicates the percentage of CPU idle time.
wa: Indicates the percentage of time spent waiting for IO operations.
hi: Indicates the time proportion of hard interrupt requests.
si: Indicates the time proportion of soft interrupt requests.
st: If false, no virtual machines need to be replaced. If true, some virtual machines are compressed.
And finally the memory usage:
MiB Mem: Displays the usage of physical memory.
total: total physical memory.
free: Free physical memory.
used: used physical memory.
buff/cache: The amount of memory used by the cache.
MiB Swap: Displays the usage of the swap partition.
total: total swap partition size.
free: Free swap partition size.
used: used swap partition size.
avail Mem: remaining available memory.
The final process list includes:
PID: Process ID number.
USER: The username of the process owner.
PR: Process priority.
NI: The nice value of the process, used to adjust the priority of the process.
VIRT: The size of virtual memory occupied by the process.
RES: The size of physical memory occupied by the process.
SHR: shared memory size.
S: Process state (D=uninterruptible sleep state, R=running, S=sleep, T=trace/stop, Z=zombie process).
%CPU: The percentage of time the process currently occupies the CPU.
%MEM: The percentage of physical memory occupied by the process.
TIME+: The total time the process occupies the CPU.
COMMAND: Command name and parameters.