Linux Bird's Linux private cuisine basic study finishing (11)

1. Drop the command directly into the background to execute "&" and Add "&" at the end of the command.
Leave your current job in the background and pause: [ctrl]+z

2. Jobs [-lrs]: View the current background work status.
Parameters:
-L: The PID numbers are listed in addition to the job number and command string;
-R: Lists the work being run in the background;
-S: Lists the work that is in the background stop.

3. FG%jobnumber: Take the backstage work to the front desk for execution.
Parameters:
No parameters: Default removal of work with +;
%jobnumber:jobnumber is the work number,% can be omitted.

4. BG%jobnumber: Make the work in the background state become operational.

5. Kill-signal%jobnumber/kill-l: Manage work in the background.
Parameters:
-L: Lists the current signal signals that kill can use;
-signal: Represents what instructions are given to the work behind, and the common code is as follows:
-1: Re-read the configuration file;
-2: Represented with by keyboard input [ctrl]+c the same operation;
-9: Immediately forcibly delete a job;
-15: Grow a job in a normal way (default).

6. Nohup [Commands and parameters]: working at the terminal front desk after going offline
nohup [command and Parameters] &: Works offline after the terminal.

7. PS aux: View all process data of the system
Ps-la: View all system data
PS AXJF: Together with part of the process tree State.
Parameters:
-A: All processes are displayed with the same effect as-e;
-A: All processes not related to terminal;
-U: Effective user-related processes;
x: Commonly used with the A parameter to list more complete information;
Output format planning:
L: A longer, more detailed list of PID information;
J: Working format;
-F: Make a more complete output.

8. Ps-l display the item's logo description:
F: Represents this process flag, which describes the permissions of the process, common numbers are:
4: The permission to represent the process is root;
1: Represents a child process that can be fork and cannot be actually exec.
S: Represents the state of the process, the main states are:
R (Running): The process is in progress;
S (Sleep): The process is sleeping, but can be awakened;
D: Sleep state that cannot be awakened, usually this process may be waiting for I/O;
T: Stop state, which may be in work control (background pause) or in a debug state;
Z (Zombie): "Zombie" state, the process has terminated but cannot be removed from memory.
Uid/pid/ppid: The table that the process is owned by the UID/process PID number/PID number of the parent process;
C: Represents CPU utilization, in percent;
Pri/ni:prioity/nice, which represents the priority of the process being executed by the CPU, the smaller the number represents, the faster the process is executed by the CPU;
Addr/sz/wchan: All memory-related, ADDR is a kernel function that indicates which part of the memory the process is in, and if it is a running process, it will typically display "-". SZ represents how much memory this process uses. Wchan indicates whether the current process is running, if-that is, it is running;
TTY: The terminal location of the lander, using the dynamic Terminal Interface (pts/n) for remote login;
Time: The CPU time that is used, which is how long the process actually spends the CPU running;
CMD: Describes the process command that caused the program to fire.

9. PS aux Display logo description of the project.
User: Which account the process belongs to;
PID: Process identifier of the process;
%CPU: The percentage of CPU resources that are used by the process;
%MEM: The percentage of physical memory occupied by the process;
VSZ: Virtual memory used by the process (KB);
RSS: The amount of fixed memory that the process occupies (KB);
TTY: Which terminal the process is running on;
STAT: The current state of the process;
Start: The start time of the process being triggered;
Time: When the process actually uses the CPU to run;
Command: The actual commands for the process.

Top [-D number] | Top [-BNP]: Dynamically view changes to the process.
Parameters:
-D: The number of seconds can be followed, that is, the entire process interface update seconds, the default is 5 seconds;
-B: Execute top in batches, usually with data flow redirection to output batch results as files;
-N: Paired with-B, several top output results are required;
-P: Specify some PID for viewing detection.
Key commands that can be used during top execution:
?: Displays the key commands that can be entered in top;
P: The use of CPU resources to sort the display;
M: The use of memory resources to sort the display;
N: Sort by PID;
T: The CPU Time accumulated (time+) ordered by the process;
K: Give a signal to a PID;
R: Give a certain PID a nice value again;
Q: Leave top.

Pstree [-a|-u] [-up]: Lists the process tree.
Parameters:
-A: connections between each process tree are connected in ASCII characters;
-U: Connections between each process tree are connected in UTF8 characters, and there may be errors under some terminal interfaces;
-P: Simultaneously lists the PID of each process;
-U: Lists the account name of each process.

Killall [-iie] [command name]: give the signal directly through the process name.
Parameters:
-i:interactive, interactive mode, if need to delete, will appear prompt to the user;
-e:exact, indicating that the command name followed is consistent, but the entire command name cannot exceed 15 characters;
-I: Command name ignores case.

Nice [-N number] command: New nice value given new command.
Parameters:
-N: followed by a number, the range of values is -20~19.

Renice [number] PID: Re-set the nice value of the existing process.

. free [-B|-K|-M|-G] [-t]: view memory usage.
Parameters:
-B|-K|-M|-G: Display memory in B, KB, MB, GB;
-T: Displays the total amount of physical memory and swap in the final result of the output.

uname [-asrmpi]: View system and kernel-related information.
Parameters:
-A: All system-related information, including the following parameters;
-S: System kernel name;
-R: Kernel version;
-M: The hardware name of the system;
The type of-p:cpu;
-I: Hardware platform.

Uptime: Check the system startup time and workload.

netstat [-ATUNLP]: Tracking network.
Parameters:
-A: The current system on all the connection, monitoring, socket data are listed;
-T: Lists data for TCP network packets;
-U: Lists data for UDP network packets;
-N: The service name of the process is not listed and is displayed as a port number;
-L: List the services currently being monitored by the network;
-P: Lists the process PID for the Network service.

Vmstat [A] [latency [total number of detections]]:cpu memory and other resource changes
Vmstat [-fs] [-S unit] [-d] [-P partition]: detects system resource changes.
Parameters:
-A: Use Inactive/active (active or not) to replace buffer/cache memory output information;
-F: Lists the number of processes in the system fork so far;
-S: A description of the list of memory changes caused by some events (booting up to date);
-S: The rear can be connected to units, such as M, K, etc.;
-D: Lists the total read and write statistics of the disk;
-P: The partitions are listed later to show the total read and write statistics for this partition.

fuser [-UMV] [-K [i] [-signal] File/dir: Locate the program that is using the file through the file.
Parameters:
-U: In addition to the PID of the process, the owner of the process is also listed;
-M: The file name next to it will take the initiative to mention the top level of the filesystem;
-V: You can list the full relevance of each file to the program and the command;
-K: Find the PID using the file/directory, and try to give this PID by Sigkill this signal;
-I: Must be combined with-K to ask the user before removing the PID;
-signal: Specifies the type of signal given.

lsof [-auu] [+d]: Lists the file names that were opened by the process.
Parameters:
No parameters: Lists all files or devices on the system that have been opened;
-A: Multiple data needs to be "set up at the same time" to display the results;
-U: Lists only the socket file types of the Unix like system;
-u: followed by username, which lists the files opened by the user-related process;
+d: Follow the directory, and find the file that is already open under a directory.

pidof [-SX] program_name: Find the PID of a process that is executing.
Parameters:
-S: Lists only one PID and not all PID;
-X: Also lists the PID of the program_name possible ppid that process.