Foreword: This blog is mainly for the notes of the online class of MOOC. Partition and formatting of the system partition. Thanks to the teacher for explaining the
A few days when I was in the middle of a computer, I also encountered a problem about partitioning: the difference between the primary partition and the logical partition was recorded in this blog.
1. The concept of partition
First, what is the partition? Partitioning is actually that our hard disk needs to be divided into several small areas to store different files. Of course, this different file is only logical. If you want to fill all the small movies in C, D and E, you will not taste it. No, but in general, we need the C drive as the system drive, and each of the other drives also has its own role, so that we can use it very conveniently, especially for easy file search.
分区 is mainly divided into main partition, extended partition and logical partition;
here to talk about the difference between the primary partition and the extended partition:
主分区 is generally the boot partition of the system, also Call the boot partition , generally we turn it into a C drive as a system disk, in order to boot the computer boot. The
extension partition is the rest of the main partition, but the extension partition cannot be used directly. We need to divide it into smaller logical partitions such as D drive, E drive and the like.
注意: The capacity between the main partition and the extended partition is independent , in the disk management of the window, even if there is still unallocated hard disk space in the extended partition, even this hard disk The space is on the right side of the primary partition, and you cannot extend it to the primary partition using the Expand Volume feature!
ps: DiskGenius can be used to adjust the primary partition and extended partition.
The main partition has a limit, can only have 4 main partitions
Why can there be only 4 main partitions?
This is determined by the structure of the hard disk. The hard disk divides itself into sectors of equal size, each sector is 512 bytes, of which 446 bytes are used to record the startup information, and the remaining 64 bytes are used for partition representation. Each of the 64 bytes represents one partition, so a maximum of 4 partitions.
In order to break through the limitations of 4 partitions, we can take one of the primary partitions as an extended partition (at most, there can only be one extended partition)
Format is not To clear the data, clearing the data is just an additional function. The purpose of formatting is to write to the file system.
Format mainly did two jobs:
- split the entire partition into blocks of equal size, each block is 4kb by default (this can be changed), this is our storage file The smallest space. (If a data size is 10kb, it needs to occupy three data blocks, even if one of the data blocks still has 2kb remaining, you can't put any other data.)
- Do a partition list (node). The ID, modification time, authority, data save address, etc. of the file are recorded on the table. When the file is taken, the list is read first, and then the specific file is extracted according to the information provided by the list.