The volume of a flash drive is 8 GB, does the computer see 7.20 GB?

Question

Iron

Explain to me clearly why the volume of the flash drive is less than stated? I know that the manufacturer considers 1 GB = 1000 MB, and the machine considers 1 GB = 1024 MB. So what? if the machine thinks so, then it should not be 8 GB, but 8192 is actually less than 8. Explain intelligibly why this happens?

Answer 1

I'll just take the answer out of the discussions.
The capacity of mechanical disks and SSDs is unformatted available to the user in decimal units. For them, you need to subtract:
• the conversion factor from decimal gigabytes to more familiar binary gigabytes (or gi bi bytes, as they were recently called);
• main boot sector;
• partition table, partition boot sectors, hidden partitions, unpartitioned space;
• technical fields of the file system.
The technical fields of the screw/SSD are hidden and do not need to be subtracted from the nominal capacity.
The capacity of flash drives is the total capacity of the memory chips in binary units. For flash drives, subtract:
• technical fields of the flash drive itself (they contain at least a table of bad sectors, hard-coded at the factory);
• main boot sector;
• partition table, partition boot sectors, hidden partitions, unpartitioned space (if any; more often flash drives are formatted into a single partition);
• technical fields of the file system.
Due to the peculiarities of addressing, it does not make sense to make non -binary size semiconductor memory chips. It's just that a flash drive has one or two chips, an SSD has a whole battery, and so that wear and tear, the constant companion of the system partition, does not make a hole in the SSD, there are complex mechanisms for sector reservation and wear balancing. Therefore, in the SSD, the principle is a hard drive, not a flash drive.
A "decimal round" figure is a good estimate of how much will fit on a flash drive. The figure is not exact, because depends on the model of the flash drive and the file system on it, but very close to reality. And on the hard drive so much is guaranteed not to fit.
www.ixbt.com/storage/flashdrives/svodka/size.shtml
Here at this link we see that in Windows both a little more than 4 billion can be available, and a little less. And if we take the unformatted capacity of the first flash drive that came across, I got 4039114752 bytes, round plus 1%. For comparison: the unformatted capacity of my hitachi will be 2000395698176 bytes - round plus 0.02%. Here's the difference between a flash drive and a hard drive.
PS I have only mechanical disks for the sake of economy, tomorrow at work I will check the capacity of the SSD.
UPD.Looked. "SamSun" unformatted volume of 256.052.822.016 bytes. Formatted into one partition with a volume of 255.466.663.936. So here it is clearly in a hard drive, with a backlog of 0.02%.
PPS Let's take a real Verbatim flash drive on 8G = 8589934592.
If we subtract the technical fields, we get the unformatted size, which is 7640M = 8011120640. 579 million bytes eaten.
The boot sector and partition table are minuscule.
The technical fields of the file system are much more occupied. Since 8010067968 bytes are available on the disk, only 1.05 million are eaten. But this is NTFS, there probably is no file allocation table, which always occupies certain sectors.
Indeed, formatting in FAT gave a size of 7993294848 bytes, i.e. FAT technical fields took 17.8 million.

Answer 2

For the volume is written in gigabytes .
1 gigabyte - 1000 megabytes .
And file systems show the volume in gigibytes .
1 gig and byte = 1024 meb and bytes.
The fact is that our inadequate government does not understand anything in IT.
https://ru.wikipedia.org/wiki/%D0%93%D0%B8%D0%B3%D...
// EDIT
On the territory of the Russian Federation, the term GB must be used to denote 230 = 1,073,741,824 bytes, according to the Decree of the Government of the Russian Federation adopted in 2009:
Although, GBtyte = Gigabyte, GiByte = Gigabyte.

Answer 3

this is how my brother died