Is Linux written in assembly language?

Tochecksysteminformation,usebuilt-intoolsdependingonyourOS:1.OnWindows,pressWin R,typemsinfo32fordetailedspecs,checkSettings>System>Aboutforbasics,oruseTaskManager’sPerformancetabforlivedata.2.OnmacOS,clicktheApplemenu>AboutThisMacforcoredet

Swappiness is a kernel parameter that controls the priority of memory and swap space in Linux systems. It takes values ​​0-100. The higher the value, the more it tends to use swap. 1. You can view the current value through cat/proc/sys/vm/swappiness; 2. Use sudosysctlvm.swappiness=X to temporarily modify it immediately but restart fails; 3. Permanent modification requires editing /etc/sysctl.conf to add or modify vm.swappiness=X and execute sudosysctl-p application; Recommended settings: Notebook/desktop (large memory) set 10 or lower, server (SSD large amount of memory) 10~30, VPS or small memory

The core of configuring service resource limitations is to prevent a service from occupying too many system resources, thereby affecting other services or causing system instability. The reason for setting resource limits is that many services have no upper limit by default, especially in containerized or microservice architectures, resource abuse of a single service may cause the entire node to crash; at the same time, in a multi-tenant environment, resource limits ensure fairness and service quality. The methods to set resource restrictions in Linux systems include: 1. Use the ulimit command to temporarily set, such as ulimit-n2048 to set the maximum number of open files; 2. Modify /etc/security/limits.conf to achieve persistent configuration; 3. For the service managed by systemd, in the service file

The slow network speed may be because the network card speed does not meet expectations. Linux users can use ethtool to view the network card speed; if it is in a low speed state, you need to check the network cable or switch port. Windows users can view the connection speed through Task Manager, but the information is limited and driver problems may be required. Secondly, confirm whether the negotiation mode between the network card and the switch is consistent. It is recommended to set it to Auto-negotiation or manually unified configuration. In addition, the network cable type affects the speed. Cat5e supports gigabit, Cat6a or above only supports 10Gbps. Old or inferior network cables will cause a speed drop. Finally, switch port performance may also become a bottleneck, and it is recommended to replace high-quality network cables or access higher-spec switches to troubleshoot problems.

Ansible is a client-free, SSH-based automated configuration management tool suitable for deployment, configuration and application orchestration. 1. Install Ansible and configure the basic environment: Use package manager to install on Ubuntu or CentOS, configure SSH password-free login and edit /etc/ansible/hosts to define host grouping; 2. Use Ad-hoc command to quickly execute tasks: such as performing one-time operations with modules such as ping, copy, service; 3. Write Playbook to implement automated processes: define task processes through YAML format, support multi-step operations such as installation and startup services, and can be reused and versioned; 4. Use variables and roles to improve flexibility:

The easiest and most reliable way to check whether the directory exists in Bash is to use the conditional test with the -d option. The specific method is to judge by if[-d"/path/to/dir"], and if the path exists and is a directory, it returns true; this method will follow the symbolic link, and if the path is a symbolic link linked to the directory, it will also return true; combined with variables, dynamic path checking can be implemented, and variables (such as "$MY_DIR") should be wrapped in quotes to safely handle paths with spaces or special characters; xargs can also be used to remove unnecessary white spaces in the path; if the influence of symbolic links needs to be excluded, you can first use -L to detect whether the path is a symbolic link, and then use -d to confirm whether it is

To find processes by name in Linux, the most common method is to use the ps command combined with grep. First execute psaux to list all processes, and then filter the target name through grep. For example, psaux|grepnginx can view nginx process information, where the first line shows the running process details, and the second behavior grep's own process needs to be ignored; if you are not sure about the name case, psaux|grep-inginx can ignore case queries. If you only need to check whether the process exists and get the PID, it is recommended to use pgrepnginx, which is simple and only the process ID. Adding the -l parameter can display the name pgrep-lnginx at the same time. -i also supports ignoring upper and lower case. for

dig is a command line tool for quickly querying DNS information. 1. Query basic records: Use digexample.com to check A records, digMXexample.com to check mail server, digCNAMEwww.example.com to check alias records, and the result is ANSWERSECTION. 2. Specify the DNS server: dig@8.8.8.8 example.com can bypass local DNS. 3. Simplified output: Adding short parameters only displays key information, such as digestample.com short. 4. Reverse query: dig-x93.184.216.34 can check domain names through IP, and be used for mail verification and other scenarios.