" Record high-level commands some common Linux "
The top command: dynamically displays the current process consumes the most resources information, three seconds to refresh.
top basic view:
top - 17:11:03 up 6:52, 2 users, load average: 0.00, 0.00, 0.00
Tasks: 82 total, 1 running, 81 sleeping, 0 stopped, 0 zombie
Cpu(s): 0.0%us, 0.3%sy, 0.0%ni, 99.7%id, 0.0%wa, 0.0%hi, 0.0%si, 0.0%st
Mem: 1020296k total, 289188k used, 731108k free, 12268k buffers
Swap: 2064376k total, 0k used, 2064376k free, 97536k cached
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
1186 root 20 0 403m 12m 5872 S 0.3 1.3 0:02.60 httpd
1577 nobody 20 0 1203m 37m 8424 S 0.3 3.7 0:08.47 httpd
1860 root 20 0 15020 1284 1000 R 0.3 0.1 0:00.19 top
1 root 20 0 19232 1488 1220 S 0.0 0.1 0:00.83 init
2 root 20 0 0 0 0 S 0.0 0.0 0:00.00 kthreadd
3 root RT 0 0 0 0 S 0.0 0.0 0:00.00 migration/
First, the first five lines Detailed statistics
first row:
top - 17:11:03 up 6:52, 2 users, load average: 0.00, 0.00, 0.00
Up 6:52 17:11:03 # current system time, the system has been running for 6 hours 52 minutes
2 the Users # There are currently 2 users log into the system the Load Average: 0.00, 0.00, 0.00 # 1 minute, 5 minutes, 15 minutes system load Happening
second line:
Tasks: 82 total, 1 running, 81 sleeping, 0 stopped, 0 zombie
# Task (process): A total of 82 current process, an operation, 81 in a sleep state, stop state 0, 0 zombie state
The third row:
People (s): 0.0% us, 0.3% sy, 0.0% Ni, 99.7% id, when 0.0%, 0.0% hi, 0.0% si, 0.0% st
#cpu status:
# Us-- user space occupied by cpu percentage
# Sy-- kernel space occupied by cpu percentage
# Ni-- changed priority process cpu occupancy percentage
# Id-- idle cpu percentage
# Wa - I / O Input / output waiting cpu occupancy percentage
# Hi-- hardware interrupt cpu occupancy percentage
# Si-- soft interrupt cpu occupancy percentage
# St-- virtual cpu cpu percentage of the actual waiting time
Fourth row:
Mem: 1020296k total, 289188k used, 731108k free, 12268k buffers
# Total physical memory, total amount of memory in use, the total amount of free memory, the kernel buffer zone stock
The fifth line:
Swap: 2064376k total, 0k used, 2064376k free, 97536k cached
# Total amount swap swap, swap the total amount used, the total amount of free exchange zone, buffer
Second, the process Detailed information
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 1186 root 20 0 403m 12m 5872 S 0.3 1.3 0:02.60 httpd 1577 nobody 20 0 1203m 37m 8424 S 0.3 3.7 0:08.47 httpd
# PID-- process ID
# USER-- process owner user name
# PR-- process scheduling priority value
# NI-- process nice value (priority), the smaller the value the higher the priority
# VIRT-- the total amount of virtual memory used by the process in kb
# RES-- resident memory size in kb
Shared memory size # SHR-- process used in kb
# S-- process status, D uninterruptible sleep state run R T S sleep state tracking / stop mode Z Zombie state
#% CPU-- last update to the current occupancy percentage of CPU time
The percentage of physical memory used by the process #% MEM--
#TIME + - CPU time used by the process in total, 1/100 second unit
# COMMAND-- command name / command line