Linux Learning Essays-common commands for system daily management

Source: Internet
Author: User
Tags cpu usage disk usage

1:w View the overall system load, unable to view the specific load, such as memory, disk 23:25:20 up min, 2 users, load average:0.00, 0.01, 0.01 USER TTY from [email protected] IDLE jcpu PCPU Flex tty1-23:13 12:08 0.01s 0.01s-bash Flex pts/0 192.168.75.1 23:13 0.00s 0.02s 0.00s tmuxThe first line shows the time, system uptime, number of logged-on users, CPU load: 1-minute average load, 5-minute average load, 15-minute average load load values are normal as long as the number of CPUs is not exceeded 2:cat/etc/cpuinfo can view cup information # cat/proc/cpuinfo |grep ' processor ' CPU number # grep-c ' physical ID '/proc/cpuinfo number of physical CPUs 3:vmstat can monitor the status of the system # vmstat 1 5 1 second interval output 5 times # vmstat 1 1-second interval output procs-----------Memory-------------Swap-------io------System-------CPU----- r b swpd free buff cache si so bi bo in CS us sy ID WA St 1 0 0 1643624 20552 105072 0 0 1 0 0 1 0 procs: Displaying process-related information R indicates the number of processes running and waiting for CPU time slices, greater than the number of CPUs, indicating that the CPU is not enough B Indicates the number of processes waiting for resources, IO memory, etc., longer than 1, there will be problems Memory: RAM information SWPD indicates the amount of memory switched to the memory partition Free Memory the buffer size at which the buff will be written to disk cache size that is read from disk by the cache swap: Swapping of memory The amount of data written to memory in the SI swap areaSo memory writes the amount of data in the swap area IO: Show disk usage data volume of BI read disk The amount of data that Bo writes to disk System: Displays the number of interrupts sent during the acquisition intervalThe number of interrupts per second observed in a time interval the number of context switches generated by CS per second CPU: Displays CPU usage status % CPU time spent by US The SY system spends more time on the CPU than the ID Cup is in an idle state longer than wa io Waits more time to occupy than St steals more CPU time than usual 0 4 Top: Dynamic monitoring system of resources occupied by the process, 3 second transformation once into the shift+m by memory sort by 1 can show each CPU running state #top-bn1 Once printed out, often in the shell top-00:47:01 up 1:34, 2 users, Load average:0.00, 0.00, 0.00 tasks:152 Total, 1 running, 151 sleeping, 0 stopped, 0 zombie Cpu (s): 0.1%us, 0.1%sy, 0.0%ni, 99.8%id, 0.0%wa, 0.0%hi, 0.0%si , 0.0%st mem:1906900k Total, 268400k used, 1638500k free, 22432k buffers swap:2031612k Total, 0k used, 2031612k free, 107984k cached PID USER PR NI VIRT RES SHR S%cpu%MEM time+ COMMAND Root 0 0 0 0 S 0.3 0.0 0:04.23 EVENTS/2 1478 root 0 173m 8008 4504 S 0.3 0.4 0:08.93 VMTOOLSD
Load average indicates system load
Tasks indicates the number of processes Process list: main focus on RES: often memory size%CPU using CPU%men memory consumption 5 SAR command can monitor all resources of the system, and can print historical information View network card traffic #sar-N DEV #sar-N DEV 1 5 View real-time data volume 1 seconds once #sar-n DEV 1 View real-time data volume unlimited refresh #sar-N dev-f/var/log/sa/sa30 View historical data traffic /var/log/sa/stored log files 12:00:01 AM IFACE rxpck/s txpck/s rxkb/s txkb/s rxcmp/s txcmp/s rxmcst/s 12:10:01 AM Lo 0.00 0.00 0.00 0.00 0.00 0.00 0.00 12:10:01 AM eth0 0.62 0.04 0.04 0.01 0.00 0.00 0.00 12:10:01 AM eth1 0.59 0.01 0.04 0.00 0.00 0.00 0.00   RXPCK/S indicates the number of packets received per second txpck/s Indicates the number of packets per second
rxkb/s amount of data received per second txkb/s amount of data sent per second 5 free View memory conditionTotal used free shared buffers cached mem:1906900 274296 1632604 232 24268 111232 -/+ buffers/cache:138796 1768104 swap:2031612 0 2031612 6 PS Viewing system processes #ps aux |grep ' tmux ' can display process status USER PID%cpu%MEM VSZ RSS TTY STAT START time COMMAND Flex 2850 0.0 0.0 23712 1116 pts/0 s+ May29 0:00 tmux Flex 2852 0.0 0.1 26528 2068? Ss May29 0:05 Tmux Flex 4502 0.0 0.0 103308 852 pts/1 s+ 01:20 0:00 grep tmux PID: Process ID kill-9 pid can kill process STAT: Indicates the status of the process D: Represents a process that cannot be interrupted, typically an IO R: Represents a running process S: Indicates that the process is already terminal, mostly the process is this state T: Represents a paused process S: Represents the main process +: Represents a process running in the foreground   7 #netstat The-LNP print system started those ports. #netstat-an Print network connection status 8 # tcpdump-nn-i eth1 Grab Kit Tool-I back-up network card 9 Wireshark Grab Bag tool # Yum Install Wireshark installation                                

Linux Learning Essays-common commands for system daily management

Related Article

Contact Us

The content source of this page is from Internet, which doesn't represent Alibaba Cloud's opinion; products and services mentioned on that page don't have any relationship with Alibaba Cloud. If the content of the page makes you feel confusing, please write us an email, we will handle the problem within 5 days after receiving your email.

If you find any instances of plagiarism from the community, please send an email to: info-contact@alibabacloud.com and provide relevant evidence. A staff member will contact you within 5 working days.

A Free Trial That Lets You Build Big!

Start building with 50+ products and up to 12 months usage for Elastic Compute Service

  • Sales Support

    1 on 1 presale consultation

  • After-Sales Support

    24/7 Technical Support 6 Free Tickets per Quarter Faster Response

  • Alibaba Cloud offers highly flexible support services tailored to meet your exact needs.