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1. Process ManagementProcess Introduction: A process is an executing program or command, each process is a running entity, has its own address space, and consumes a certain amount of system resources. the role of process management:Determine server health status (top)View all processes in the system (PS)kill Process (Kill) To view all processes on the system:PS aux #查看系统中所有的进程, using the BSD (UNIX) operating system formatPs-le #查看系统中所有的进程, using the Linux standard command formatField Description: View System health status: Top [options] View process tree: Pstreeoption:-P show process PID-U Displays the user who owns the process Terminate process: Killto view the available process signals: Kill-l Restart process: kill-1 pidforced termination process: kill-9 pidNormal End process: kill-15 pid or kill PIDkill process by process name: killall [Options] [signal] Process nameoption:-I interactive, asking if you want to kill a process-I ignores process name capitalizationterminate process by process name: Pkill [Options] [signal] Process nameoption:-T terminal number: Kick the user by terminal numberExample: 1) Use the W command to view the user who is logged in to the computer, 2) the process of terminating terminal logon with Pkill: pkill-t-9 PTS/1
2. Work Managementput the process into the backgroundmethod One: Add & (Run the process in the background until completed) after executing a commandmethod Two: After executing a command, press CTRL + Z shortcut key (background pause the process)View work in the background: jobs [-l]option:-l show working PIDRestore background paused work to foreground execution: FG% Work numberparameter:% Work number% can be omitted, but note the difference between work number and PIDRestore background paused work to background execution: BG% work numberNote: Background recovery executes commands that cannot interact with the foreground, otherwise it cannot be restored to background execution
3. System Resource ViewMonitoring System resources command: Vmstat [refresh delay] [refresh]kernel detection information at boot: DMESGView Memory usage Status: freeNote: The difference between caching and buffering--caching is used to speed up the "read" of data from the hard disk, and buffering is used to speed up the data "write" to the hard diskDisplays the system start time and average load, which is the first line of the top command: UptimeView system and kernel related information: uname [options]option:-A To view all relevant information about the system- R View Kernel version- s view kernel namedetermine the number of bits of the current system: File/bin/lsView the current hairstyle version of the Linux system: Lsb_release-alist The file information that the process opened or used: lsof [options]Options:
4. System Timing TasksCrond Services Management and access control: Service Crond restart (or set boot from: Chkconfig crond on)User's Crond settings: crontab [Options]options:-e edit crontab timed tasks- L Query crontab task-R Delete all crontab tasks for the current usertimed Task Format: * * * * * command Special Symbols: Simple example: +++++++++++++++++++++++++ +++++linux System Management +++++++++++++++++++++++++++++++
Linux Learning Notes-System Management (11)
