ode learning management system

[Django] design of the user permission Learning Series Self-owned permission management system design idea, django permission management system If you encounter permission operation problems when reading this article, please refer to the first two chapters of this series! By

18.3 "Linux learning is not difficult"File System Management (3): InLinuxcreating a file system in the systemuse the MKFS command to create various file systems on a partition. the MKFS command itself does not perform the work of establishing the file system, but rather call

a data tableRight-click on the appropriate database to create a new tableEnter the data table name, stare, the following fields, you need to first click "Join?" button to add? field, first Field "userid", data type set to bigint, click Default Value column, where you can set your own active numberSave data table, prompt for no primary keySet the primary key, right-click on the UserID field row, create a new index PRIMARY, create the Index management

and CPU The primary way to transfer data between device drivers : I/O device drivers are software modules that deal directly with hardware. " interrupt handlers and device drivers are typically completed by the hardware developer " device independent layer : i/o software except for device drivers User-level software : The user uses the device's system call or API. The usual I/O is called by the library

point in time only one process access to resources, such as memory resources access: for the entire memory resources are parallel access, However, it is mutually exclusive access for a memory unit of the smallest granularity in memory.Virtualization (leveraging multi-channel program design techniques to make each user (process/program) feel that the computer is acting as if it were a separate service)Async (The execution of the program is not consistent, but a walk-stop, forward speed is unpred

can hold is 16GB, which is consistent with the file restriction table results. However, this method is not applicable when the block size is 2KB or 4KB, because the block larger than 2KB will be limited by the EXT2 file system itself, and the calculation results and the restriction table.(3) Super blockwhere this block records information about the entire file system, the main records are:Block and the tot

Operating System Concepts Learning Note 5 Operating System Management brief process managementA program that is in execution is called a process.The process requires a certain amount of resources (including CPU time, memory, files, I/O devices) to complete the task. These resources can be assigned to a process when the

system continuously provides fast response times. 3 . ScalabilityXFS is a full 64-bit file system that can support up to million T bytes of storage space. Support for oversized files and small file sizes is outstanding and supports a large number of directories. XFS uses a high table structure to ensure that the file system can be quickly searched and quickly al

15:02 F084B8A6-C9AB-425B-99DA-B64CB35E4FC2. /.. /sda5// Disk Partitioning /dev/sda5 of the UUID is a F084B8A6-C9AB-425B-99DA-B64CB35E4FC2then edit /etc/fstab file , Add the following at the end of the file. uuid= f084b8a6-c9ab-425b-99da-b64cb35e4fc2/mnt/www XFS Defaults 1 2This article extracts from "Linux Learning is not difficult" textbook, which is one of the most practical, theoretical and practical Linux Introductory materials. To read the ent

MySQL learning notes _ overview of MySQL database management system, learning notes _ learn MySQLZookeeper 1. MySQL Architecture C/S: client/server Architecture MySQL DBMS (Data Bank Management System): Database

Large enterprises spend nearly millions of dollars each year training employees, business partners and providers. Learning management systems are becoming increasingly complex, not only to meet physical equipment and web-based training delivery needs, but also to meet the needs of planning and scheduling activities. The implementation of the learning

How messages are delivered Two primitives for communication between processes Send (Destination,message) Receive (Sourse,message) Synchronization of Message Delivery Three modes of synchronization Blocking receive Addressing in message delivery Indirect addressi

Operating system learning notes-memory management The content of this article is as follows: 1. Purpose of Memory Management 2. core tasks of Memory Management 3. Various memory management methods: 3.1 partition

increase the additional overhead of the system　　　　　　Hardware methodsControl synchronization and mutual exclusion by shielding interrupts or by using specialized machine directivesReduces system overhead, requires too strong hardware constraints, and can cause process starvation and deadlock, without becoming a common solution　　　　　　Signal Volume method (emphasis)Special support by the operating

Operating System Concepts Learning note 15 memory management (i) backgroundMemory is the center of modern computer operation. Memory has a very big group of words or bytes, and each word or byte has its own address. The CPU extracts instructions from memory based on the value of the program counter (PC), which can cause further reads and writes to a specific memo

line to the file headerCtrl+d: Turn half screen at the end of the fileCtrl+u: Turn half screen to file headerString search:/keyword: From the file header to the tailKeyword: from the tail of the file to the headerN: Shows the next foundN: Displays the last foundExit Esc+q4, Info Command, there is a hyperlink document, info is the information page, provide the author, version, when the release of more detailed information, man manual is to tell you how to use,5, README; most programs have a corr

read the time of the last Anacron execution in/var/spool/anacron/cron.daily.(2) compared with the current time, if two times difference is more than one day, perform cron.daily work.(3) Performing this work is only between 03:00-22:00.(4) The forced delay time is 5 minutes when performing the work, and then a random delay of 0-45 minutes(5) Use the Nice command to specify the default priority and use the Run-parts script to execute all executables in the/etc/cron.daily directory.Note: Anacron w

" - Represents a continuous time range. such as "0 5 * * 1-6 command", which represents the execution of commands from Monday to Saturday 5:0 A.M. */n Represents how often it is executed. Like "*/10 * * * * * * * * * * * * * * * * * * * * * * * * * * * command" time meaning TD valign= "Top" width= "196" > Execute command at 22:45 45 22 * * * command 0 17 * * * 1 command