Limits the capacity of the hard disk

Is a hard disk

Hard disk, a temporary or permanent preservation programs and user data, to keep a large amount of memory is
In a typical file access latency high-capacity, despite the fact that usually, but sometimes as an external storage device, magnetic tape used sequential data file access structure itself must be long, however, only hard disk, the disk arm control file access during standby time was short, because the most common external storage devices




Comparison

Round reputation of rotating media disk (disk), the etymology of the means, divided into the type of floppy and hard disk in the computer floppy disk magnetic media if the soft coated plastic resin magnetic material to be coated in a low rotational speed easy control of the disk arm is wide and the width of the track work, has achieved a very small metallic disk coated with a magnetic material, and coating that works in a high-speed rotation and the width of the track designed for high capacity hard disk, however, the metallic of the disk is usually fixed, and requires a very fine-grained control on the disk cancer
CDROM as built-in, fixed disk, which is to replace the disk in the drive, but if you can write fine-grained control to track because the track width wide format




The model of the disk

Rotation to the physical structure of the disk storage media means that
Defined as the circumference of the track and rotate the disk arm tracks divide the circumference capacity within sectors are defined, with multiple discs to rotate the disk arm to install the head corresponding to each of the disk surface, the disk arm to control the lifting less effort and capacity can increase the number of the surface of the disk, or the number of head of Special track approach, where access to the same number of tracks as one of the number of heads in the disk arm cylinder is defined as
CHS cylinder (Cylinder), head (Head), sector (Sector) refers to this approach as the number three structure models
LBA model: Linear Block Addressing This law is in three parts, shown with one integer to convert CHS address of the internal disk addressing
Compartment and the number of RAM blocks used to access bank (bank) number of SSD's internal memory is configured to convert the LBA address to the interface will work in conjunction




Logical address

Large amounts of disk addressing of the disk to fit the configuration of the disk, but if you pass the actual address of the driver, if the logical configuration of the disk to another disk to the system and the actual configuration and can be used, depending on the need
Usually, the use of the logical address as the LBA is to use a sequential sector number
The logical address access and use of the disk drive system, so it is advantageous to use




BIOS (BIOS) of the limit

Usually, the CHS based on the disk access is possible if you pass three digits
Early 1024 cylinders, 16 heads 63 sectors as there was a limit of 504 MB of approach
Then 1024 cylinders, 255 heads, 63 sectors as it had limited access to approximately 7.84 GB of 8,032.5 MB
This 16-bit limit in the course of the argument is passed as a register in the bios, but the limitations of the hardware design is revealed while using multimedia, data processing, document processing and in the design of very large capacity because the limit is
In this case, a large amount of hard disk, even because of BIOS limitations have not been able to use the capacity of




The hierarchy of the file system limits

Once the hard disk, the mass should be
Then, the hardware should be able to access large amounts of the control
Then, in the BIOS (if not direct control) in a high-volume approach should be accessible to
MBR / GPT table this large parcel, and must support
Block management capacity for the last available file systems must be formatted as
Constraints should all approach the capacity of the structure mass (can be used)




Initial LBA

LBA basically three integers from the address is converted to an integer one, usually as a 32-bit address space on the disk, but actually only 28-bit access of the hardware is available, because there is a limit of 128 GB (LBA28 by the specification of the initial point does not call)




Extended LBA

Have had reusing a port, the port used for the CHS model of the hardware used in LBA addressing limit of 28-bit However, if you added port LBA48 to access is available to 48-bit linear sector of space called the 128 PB = 131,072 TB = 134,217,728 GB of mass can be accessed This varies depending on the system, the system need to patch rosseodo easy upgrade is possible. Therefore, the approach of the current, hardware capacity limits are not so worried about the possibility of




Extended BIOS

BIOS ROM access to a large amount of disk alone is possible, in this case, the disk LBA address and work to create the packet as an argument passed to the BIOS and works, 64-bit LBA address 8 ZB = 8,192 EB be accessible, but actually use hardware port access to the LBA, the LBA LBA48 or are constrained