Shulou(Shulou.com)06/02 Report--

At present, the disk partition scheme widely used under Windows is still MBR partition structure, but there is no doubt that GPT is the trend in the future. We can simply represent the MBR disk partition structure with the following figure (basic disk under Windows, 4 primary partitions):

MBR partition structure

In order to facilitate the computer to access the hard disk, the space on the hard disk is divided into many blocks (called sectors in English, that is, sectors), and each block is assigned an address, called logical block address (LBA).

The boot code and the hard disk partition table are stored in the first sector of the MBR disk. The function of the boot code is to instruct the computer to boot the operating system from the active partition (how to boot the operating system under BIOS); the function of the partition table is to record the partition information of the hard disk. In MBR, the size of the partition table is fixed and can hold a total of four primary partition information. Logical block addresses in the MBR partition table are represented by 32-bit binary numbers, so a total of 2 ^ 32 (2 to the 32) logical block addresses can be represented. If the size of a sector is 512 bytes, the maximum partition capacity of the hard disk is only 2TB.

The partition structure of GPT disk can be simply represented by the following figure (basic disk under Windows):

GPT partition structure

As you can see, in the first block of the GTP disk, there is also a tag similar to MBR (master boot record) called PMBR. The purpose of PMBR is that when using a partitioning tool that does not support GPT, the entire hard disk will appear as a protected partition to prevent the partition table and hard disk data from being corrupted. UEFI does not get partition information for GPT disks from PMBR. It has its own partition table, the GPT partition table.

The reason why GPT's partitioning scheme is more advanced than MBR is that the maximum number of partitions that can be customized in the GPT partition header means that the size of the GPT partition table is not fixed. In Windows, Microsoft sets the maximum number of partitions for GPT disks to 128. In addition, the logical block address (LBA) in the GPT partition scheme is represented by 64-bit binary numbers, so we can calculate how huge 2 ^ 64 is. According to our requirements, there is every reason to think that this size is about infinite. In addition, the GPT partition scheme also has a backup partition table at the end of the hard disk, which ensures that the partition information is not easily lost.

Support of GPT disk by Windows operating system

Because BIOS does not recognize GPT partitions, GPT disks under BIOS cannot be used to boot the operating system, but can be used for data storage if the operating system provides support.

UEFI can recognize both MBR and GPT partitions, so both MBR and GPT disks can be used to boot the operating system and data storage under UEFI. However, Microsoft restricts that the operating system can only be installed on GPT disk under UEFI using the Windows installer.

The following table lists the extent to which each version of the Windows operating system supports GPT disks:

32-bit Windows support for GPT partitions 64-bit Windows support for GPT partitions

Use the partition created by default by Windows installer

When we install Windows8/7 in GPT and use the Windows installer to repartition the hard drive, several partitions shown in the following table will be created by default.

Partition size type file system recovery partition (WinRE) 300MB primary partition NTFSEFI system partition 100MBEFIFAT32MSR reserved partition 128MBMSR

Windows installation partition user-specified size primary partition NTFS

Let's briefly talk about the role of these partitions:

The first recovery partition is the partition that holds the WinRE image, which is created by default only when you install Windows 8. WinRE is the abbreviation of Windows recovery environment, including system restore of origin, system image recovery (as far as we know, this function will be removed in Windows 8.1), system refresh, system reset and so on. It also automatically fails over to WinRE when the Windows 8 system fails to boot properly.

In Windows7, the WinRE and Windows installation partitions are in the same partition and are not taken out separately. In Win8, Microsoft separates WinRE and Windows installation partitions by default, and the purpose should be to maximize the reliability of WinRE. When you install Windows 8 on a MBR hard drive, you will find that the size of the reserved partition of the system has expanded from 100MB when Win7 to 350MB, and the extra space is used to hold the WinRE image.

The second partition is the partition that holds the system boot files, which is necessary to implement UEFI boot.

The third MSR partition, which is reserved by Microsoft, is not clear. It is known that converting a basic disk to a dynamic disk is the partition that will play a role.

The fourth is that we install the system is to choose the target partition. Its actual capacity = the capacity you specify-the capacity of the first few partitions.

If only the normal startup of the system is considered, then two partitions, the EFI system partition (the second) and the Windows installation partition (the fourth partition), are necessary.

Default partition of brand machines pre-installed with Windows 8 (take a Lenovo model as an example)

You will also see the partitions shown in the above table on brand machines that are pre-installed with Win8, but their sizes may vary, and you may also see other hidden partitions. The following table shows the default partition of a Lenovo pre-installed Win8 computer.

Partition size type file system recovery partition (WinRE) 1000MB primary partition NTFSEFI system partition 260MBEFIFat32MSR reserved partition 128MBMSR

OEM partition 1000MB

Windows installation partition user-specified size primary partition NTFS recovery partition (system backup) 20000MB

Compared with the partitions in the first table, the extra partitions in the second table are used for one-click recovery of the brand machine. The OEM partition is used by the brand machine to store the one-click recovery tool, while the larger recovery partition is used to store the system backup image.

This is a simple explanation of the role of some special partitions on the disk used to boot Windows's GPT partition structure, followed by a more detailed explanation of GPT, UEFI, and UEFI+GPT booting.

At present, almost all personal computers that support UEFI are 64-bit UEFI systems, which only support 64-bit Vista, 64-bit Win7 and 64-bit Win8/8.1. So you can only choose from these operating systems. Keep in mind that only the original image supports CD-ROM UEFI startup, be sure to choose to download the original Microsoft system! Recommended version: whether it is Win7, Win8 or Win8.1, professional version is recommended; KMS activation mode is recommended for activation.

Tip: friends who have downloaded the Win7 flagship version of the image, such as using a USB drive to install or boot the installation from the hard drive (described later), after preparing the installation media, you only need to delete the ei.cfg file under the sources folder to choose to install any version except the enterprise version, including the professional version.

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