Course Intermediate  11360

Course Introduction："Self-study IT Network Linux Load Balancing Video Tutorial" mainly implements Linux load balancing by performing script operations on web, lvs and Linux under nagin.

Course Advanced  17663

Course Introduction："Shangxuetang MySQL Video Tutorial" introduces you to the process from installing to using the MySQL database, and introduces the specific operations of each link in detail.

Course Advanced  11379

Course Introduction："Brothers Band Front-end Example Display Video Tutorial" introduces examples of HTML5 and CSS3 technologies to everyone, so that everyone can become more proficient in using HTML5 and CSS3.

Course Introduction：Disk scheduling algorithms include: 1. First come, first served algorithm, which schedules according to the order in which processes request access to the disk; 2. Shortest search time priority algorithm, which selects the track for scheduling processing that is closest to the track where the current head is located, so that Each search time is the shortest; 3. Scanning algorithm; 4. Loop scanning algorithm.

2021-04-16 comment 0  15249

Course Introduction：Common disk scheduling algorithms include first come, first served, shortest seek time first, scan algorithm, loop scan algorithm, simple elevator algorithm and loop LOOK algorithm. Detailed introduction: 1. First come, first served, the advantage is that it is simple to implement, but the disadvantage is that it may cause uneven disk access time, causing some requests to wait for too long; 2. The shortest seek time is given priority, and the advantage is that it can improve the disk access efficiency , but the disadvantage is that starvation problems may occur; 3. Scanning algorithm, the advantage is that it can ensure that every request will be satisfied, but the disadvantage is that the waiting time for intermediate requests is too long, etc.

2023-08-21 comment 0  3509

Course Introduction：The Linux kernel contains four types of IO schedulers, namely NoopIOscheduler, AnticipatoryIOscheduler, DeadlineIOscheduler and CFQIOscheduler. Typically, disk read and write latency is caused by the head moving to the cylinder. In order to solve this delay, the kernel mainly adopts two strategies: caching and IO scheduling algorithms. Scheduling Algorithm Concepts When a block of data is written to or read from a device, the request is placed in a queue waiting for completion. Each block device has its own queue. The I/O scheduler is responsible for maintaining the order of these queues to utilize the media more efficiently. The I/O scheduler will unordered I/O

2024-02-14 comment 0  1281

Course Introduction：Disk scheduling algorithms include: 1. First come, first served algorithm, which schedules according to the order in which processes request access to the disk; 2. Shortest search time priority algorithm, which selects the track for scheduling processing that is closest to the track where the current head is located, so that The search time is the shortest each time; 3. Scanning algorithm, in the current moving direction of the magnetic head, selects the request closest to the track where the current magnetic head is located as the next service object; 4. Cyclic scanning algorithm, based on the scanning algorithm, the magnetic head unit is specified Provide services to the mobile server, and when returning, move directly to the origin quickly without serving any requests.

2022-07-21 comment 0  8256