Graphic Operation Method for low disk space

I. Hard disk formatting
The word "format" should never be unfamiliar to a computer user. When we perform a completely new Windows installation or "clean" processing all the data on a hard disk, we often offer the "formatting" option ", to completely clear data in each partition of the hard disk. "Hard disk formatting can be performed in two different environments: Windows and DOS. Generally, when operating systems are completely installed, the "format" command under DOS is used to format the system disk. When formatting partitions other than the system disk is performed separately, in Windows, the operation is easier. You only need to right-click the hard disk to be formatted and select the format option, select quick format, and the time required is shorter.
Although the operation method and the time required for formatting are different. However, they all perform the same operation on the hard disk, that is, clearing the data on the hard disk, generating boot information, initializing the fat table, and marking the logical Bad Sectors. These operations are collectively referred to as "Advanced formatting ".
After learning about the "advanced formatting" of the hard disk, let's take a look at the process of downgrading the hard disk. Low-level formatting refers to dividing a blank disk into a cylindrical and track, and then dividing the track into several sectors, each sector is divided into the ID, Gap, and data of the identification part. Low-level formatting of hard disks is a task before advanced formatting. Currently, all hard disk manufacturers have performed low-level processing on hard disks before leaving the factory, therefore, when installing the system, we only need to initialize the fat table and perform partitioning during the advanced formatting process.
Unlike the advanced formatting operation, the low-level formatting process of the hard disk can only be completed in the DOS environment. The process of fully formatting a floppy disk under DOS can be seen as a low-level formatting of a floppy disk. It should be noted that the low-level formatting process of the hard disk is a kind of consumable operation, which will have a negative effect on the service life of the hard disk. Therefore, unless a large error occurs on the hard disk, such as a bad track on the hard disk, you must carefully perform low-level formatting. When a hard disk is affected by an external strong magnetic body or a strong magnetic field, or due to long-term use, the disk is missing from the disk segment in the format of low-level formatting, resulting in a large number of "Bad Sectors, you can use low-level formatting to re-divide the "slice ". However, the premise is that the disk is not physically scratched.
I believe that low-level formatting can be used only when multiple partitions on the hard disk fail or a large number of "bad channels" are found in advanced formatting. Hard drive damage, such as physical Bad Sectors, cannot be repaired through low-level formatting. I can imagine if the surface of a floppy disk is scratched, can it be repaired?
Ii. Low-Level formattingHard DiskOperations
Some may ask, what operations have been done to the hard disk during the hard disk downgrading process? Because the low-level formatting process of the hard disk is implemented by third-party software, the operations of different software on the hard disk are also different. To sum up, the hard disk's low-level formatting process mainly involves the following work on the hard disk.
1. Clear the slice and override the check value. In the low-level process, all the bytes in each sector are set to zero, and the check value of each sector is also written back to the initial value. This can correct some defects. For example, because the sector data does not correspond to the validation value of this sector, an ECC error is usually reported ). If it is not due to magnetic medium damage, it is very likely that the sector data will be re-matched with the validation value of the sector after being cleared, to achieve the effect of "repairing" the sector. This is the most basic operation content for each type of low-level tool and each type of hard disk, and it is also the basic reason why the low-level tool can "repair a large number of bad channels. In addition, the zero fill (zeroing) operation in DM has the same effect as the erase operation in the ibm dft tool.
2. Perform read/write checks on the slice and try to replace the defective slice. Some low-level tools perform read/write checks on each slice. If an error occurs during the reading or writing process, the slice is considered as a defective slice. Then, call the general automatic sector replacement command to try to replace the sector, which can also achieve the "Repair" effect.
3. Rewrite the ID information of the slice. Old hard disks used many years ago (such as hard disks using the st506 Interface) need to re-write the ID information of each sector and some other information that retains the track in the low-case process, at that time, non-standard tools must have such features. However, the current hard disk structure is quite different. If you use the tool for low-level storage many years ago, it will lead to many painful accidents. It's no wonder that people often shout in pain: "dangerous! Do not uncompress the hard drive! My hard drive has been broken down !"
4. Re-number all physical sectors. The number is based on the record and segment allocation parameters in the p-List (this parameter determines the number of sectors of each track, each slice is allocated with a specific ID ). When the number is specified, the system automatically skips the defective sectors recorded in the p-list so that users cannot access those defective sectors (users do not have to care about the quality of the defective sectors that will never be used ). If this process is abandoned halfway, some or even all sectors may be reported as being identified incorrectly (Sector id not found, idnf ). Note that this numbering process is based on real physical parameters. If some low-CASE tools perform low-case calculation based on logical parameters (16 Heads 63sector is the most typical, it is impossible to perform such operations.
5. Write the track servo information and re-number all tracks. Some hard disks allow you to overwrite the servo information of each track and re-assign a number to the track. The number skips the defect track based on the p-list or TS record, making it inaccessible to the user (that is, it never needs to be used. This operation is based on real physical parameters.
6. Write status parameters and modify specific parameters. Some hard disks have a status parameter that records whether the low-level process ends normally. If the low-level process is not completed normally, the entire hard disk will reject read/write operations, this parameter is typical of Fujitsu IDE hard disk and Seagate SCSI hard disk. Some hard disks may also modify some parameters based on records in the low-case process.
We often use the low-level format command in DM to perform low-level formatting, mainly for 1st and 3rd operations. It is faster and rarely damages the hard disk, but the repair effect is not obvious. In addition, the first three operations are performed in the lformat tool. Because the read/write check is performed at the same time, the operation speed is slow and some defective sectors can be replaced.
Next, we will introduce the two frequently used formatting tools in detail.
Iii. Simple formatting
First, let's introduce the DM operation.
By default, low-level formatting is not allowed when DM is started. You need to open the advanced menu of DM. You can add the parameter "dm/M" at startup or press "Alt + M" on the main interface of DM to switch to the advanced menu.

Select (m) aintenance options in the menu to go to the advanced menu.

Then select "(u) tilities" to enter the low-level formatting interface.

Next, select a hard disk that requires low-level formatting. If you only have one hard disk, press Enter. If you have multiple hard disks, select them.

Select the hard disk to be formatted, and then select "low level format" for low-level formatting.

The system will pop up a warning window, and press "Alt + C" to confirm.

Next, the system prompts you to confirm again, asking the user to confirm again. Select "yes" here ". If you want to terminate the operation at this time, you only need to select "no" to terminate the low-level formatting operation.

The system starts the hard disk low-level formatting operation, where the progress is displayed in percentage. This process will be based on the disk capacity and damage to the hard disk, the progress is very time-consuming, so you still need to wait patiently. After the progress bar reaches 100%, the hard disk's low-level formatting process ends.
Next, let's take a look at the lformat tool for low-level hard disk formatting.
Step 1: Create a boot disk in windows, copy the lformat to the boot disk, restart the computer, insert the floppy disk into the floppy disk, and start the computer from the floppy disk.
Step 2: After the system is started, enter the command lformat.exe and press the Enter key to open the main screen window of lformat. Press "Y" to start the program. If you press another key, exit the program.

Step 3: after entering the main interface window of the Low-format program, three options will appear: Select device (select drive disk), low level Current Device (low-level current drive) and exit (exit) options, use the direction key to select the first item, and then press the Enter key.

Select Disk

Disk selection Error

Step 4 after correctly selecting the disk information appears, open the drive selection dialog box, there is a red dialog box in the middle of the screen, and "which device do you want to select?" appears ?" Prompt, this prompt is to ask to select the hard disk ). The options provided here are (0, 1, 2, 3). How can we determine the drive we want to use? You can select these four numeric keys. We know that there are generally two ide interfaces on the motherboard, and a maximum of four hard disks can be connected. The simplest way to determine the disk number of our current hard disk is to open the CMOS menu, then, check the hard disk connection in the first menu. In general, one of our ide interfaces is connected to the hard disk, and the other ide interface is connected to the optical drive. At this time, record the serial number of the hard disk connection. Here we select the number key 1, and the current hard disk parameters will be displayed on the screen. If no parameter is found, the selected number is incorrect. You can press ESC to reselect it. Then we can find the hard disk information displayed on the screen, including the disk capacity, cache, number of turns, and other information.

Step 5: Start formatting. After selecting the hard disk, you can start formatting the hard disk. Select the "low level Current Device" command in the main menu and press the Enter key, "Do you want to use LBA mode (if not sure press (y/n )?" If you are sure, Press Y. Otherwise, press n. If your hard disk is larger than 540 MB, You Need To format it in LBA mode. Otherwise, the entire disk can only use MB space. Press Y to start. 3. Then the system displays a warning message indicating that all data will be lost. If you are sure to format the data, Press Y. Otherwise, press n. During the low-case process, you can press ESC to stop at any time.
After completing the formatting process, you can press ESC to return to the main menu, select the third exit, press enter to exit, and restart, and then you can start partitioning, and perform advanced formatting and installation of the operating system.