Let's have a look why these limitations exist. The arrangement of logical sectors which constitute storage devices is described by a scheme called LBA Logical Block Addressing. One label represent per sector, LBA0 stands for the first logical sector on the disk and the last LBA represent the last logical sector.
The capacity of hard drive can be calculated by multiplying the number of logical number by the size of each sector. Currently the standard size of logical sector is bytes. Thus, a 2TB hard drive will contain 3,,, byte sectors. But computer system requires 32 bit of information to represent this large number. In other words, if the disk's capacity is larger then what can be described by using 32 bits, it would require an additional bit, 33bits.
The MBR scheme sets a limit of 32 for the number of bits that can represent the number of logical sectors. The maximum number that can be addressed by 32 bit is 4,,, which is 2. That means a capacity exceed 2. In MBR partitioning scheme, the partition table takes totally 64 byte space for identify partition type, location, etc. It takes 16 bytes to record a partition's information.
Therefore, MBR partition table can hold four partitions information, which means you can create only 4 partitions on a hard drive. If you've created 4 primary partitions and there is still unallocated space, the free space will be unusable. To overcome the barrier, you can create an extend partition, a special kind of primary partition, and then create multiple logical partition in the extended partition.
Compatibility itself is divided into two cases: data compatible and system compatible. Data compatibility and system compatibility is not the same thing. All Windows versions, both 32bit and 64bit, including the latest Windows 10, are compatible with MBR in data and system compatibility. Just go head to check whether your motherboard is in BIOS mode. If your computer is brand new and it is likely to use GPT partitioning scheme. GPT is much more complicated and this part will dig a little about it.
If you are not into technical details you can skip this part to read its main features. This graph above explains disk structure of GPT partitioning scheme. LAB 0 means the first sector whose physical number is 0 and LBA represents the second sector whose physical serial number is 1.
Reserve MBR. This MBR here does not have actual function and it exists only due to the consideration of software compatibility. The GPT header defines partition number.
Basically, you can deem that there is no limitation on partition number of GPT disk. In fact, the third sector is the beginning of the actual partition table. Please note that each sector can store 4 partitions' information, which means every partition needs bytes to store partition information.
According to 3 we can calculate that each partition' information occupies a quarter of a sector, which is bytes. In contrast, the partition information is 16 bytes in MBR disk, and thus GPT partitioning method has enough space to store beginning location, total capacity and other data.
There is no need to worry about partition number or capacity. Still drawing from 3, on GPT disk all partitions' information is stored on partition table.
However, in fact, if your computer is running Windows, GPT partition table usually occupies 32 sectors which are able to save information for partitions. The rest space is reserved. In general, there won't be that many partitions on our computer, thus most space in partition table is not used.
So much about GPT scheme and it is not that complicated. As to average users, the basic thing about GPT they should keep in mind is that it supports hard drives lager than 2TB and it is the major advantage over MBR. Anything larger than that, and the extra disk space is marked as unallocated and unusable. GPT allows for 64 bits, which means that the storage limitation is 9. That's a zettabyte, which is one sextillion bytes or a trillion gigabytes.
In practice, what it really means is that GPT has no real-world limit. You can buy any capacity drive, and GPT will be able to use all of the space. MBR stores all the partition and boot data in a single place. This means that if anything gets corrupted, you'll run into a problem. If any data gets corrupted with MBR, chances are you'll only find out when your system fails to boot.
Recovery from MBR is possible but not always successful. GPT is far superior in that it stores multiple copies of the boot data across several partitions at the beginning and end of the table headers. If one partition gets corrupted, it can use the other partitions to recover. Additionally, GPT has error-detecting code that will assess the partition tables on boot and see if there's anything wrong with them.
If it detects errors, GPT can try to repair itself. While they both serve the same purpose, they are different. As a big fan of Apple products, she mainly focuses on iOS data transfer and iOS troubleshooting tips. Meanwhile, she is expanding her knowledge and skills in other fields like data recovery and disk management.
Myra is open-minded and likes both extensive and intensive reading. Other than reading and writing, she is also fond of mobile games and K-pop stars. It makes it way easier to play out what will happen after you've made all the changes. I also think the overall look and feel of EaseUS Partition Master Free makes whatever you're doing with your computer's partitions easy.
Partition Master Free can Resize, Move, Merge, Migrate, and Copy disks or partitions; convert to local, change label, defragment, check and explore partition; and much more. A premium upgrade adds free tech support and the ability to resize dynamic volumes. It won't hot image your drives or align them, but since it's coupled with a partition manager, it allows you do perform many tasks at once, instead of just cloning drives. You can move partitions around, resize them, defragment, and more, along with the other tools you'd expect from a cloning tool.
Let it manage your storage drive: resize, format, delete, clone, convert, etc. Store Download Support Live Chat. Was This Page Helpful? Read full bio. Free Download. The GUID consists of details on drives, partitions, storage sizes, boot information, and other essential data related to boot and functionality.
GPT has no partition limit , so you can have ten partitions if you want. Another difference is MBR stores all information in one place, which could get corrupted and fail.
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