Small knowledge, big challenge! This article is participating in the creation activity of “Essential Tips for Programmers”.
Irrelevant content
Haven’t on the operating system for a long time this week and began to go up, this week seems to be quite a lot of things, took an examination of mandarin and algorithm of the exam, next week to take an examination of soft, hope soft test can lead!
lead
Partition management divides memory into regions of different sizes, which are shared by concurrent processes in multi-channel environments except for one region occupied by the operating system. Partition management is one of the simplest storage management methods to satisfy multi – channel programming.
Basic principles of partition management
The basic principle of partition management is to divide each process in memory into an appropriately sized storage area to store the programs and data of each process continuously, so that each process can execute concurrently.
There are two ways to manage partitions
According to the timing of partitions, partition management can be divided into fixed partition management and dynamic partition management.
Fixed partition
Textbook definition
Fixed partition is a fixed partition of memory into several regions of varying sizes. The characteristic is that the size of the partition is fixed and the number of the partition is fixed.
For example, class
We will of the image of the fixed partition management as our class teaching building, then each classroom in our school building is a partition, the buildings before we go into class, the classroom differentiate had already finished, can’t change, the number of fixed, a classroom is how big is how much, how many of the classroom is how much that will not change.
Fixed partition features
We from vividly metaphor to explore the characteristics of the fixed partition, take, for instance, the classroom in our class, the classroom is always have a lot of empty seats are not used, and this is the waste of space, a job in the actual fixed partition always fill a fixed partition, it can form a lot of “fragments”, cause waste of space. On the other hand, we consider that if several classes are taught together, the classroom is not enough for us to enter the classroom, which corresponds to another problem of fixed partition that is unable to run large assignments.
advantages
Simple and easy
disadvantages
- Waste of space
- Unable to run large jobs