Re: FAT32 partition size limit is 2 Terabytes

Jafadmin · Post by **Jafadmin** » Sat Oct 10, 2020 8:13 pm

NOT 4GB!!!

lizardidi · Post by **lizardidi** » Sat Oct 10, 2020 10:19 pm

wow, glad to know that!!!

taersh · Post by **taersh** » Sat Oct 10, 2020 11:01 pm

Jafadmin wrote: ↑Sat Oct 10, 2020 8:13 pm NOT 4GB!!!

Ever bought a 16GB USB flash drive?
It's formatted to FAT32 by default.

I have an old Seagte USB hard drive that has 250GB.
It was and still is also formatted to FAT32 by default.

Post by **mikewalsh** » Sat Oct 10, 2020 11:22 pm

4GB is the individual FAT32 file 'size-limit', of course.....

Mike.

m1k3 · Post by **m1k3** » Wed Oct 28, 2020 1:30 am

Newer flash drives come with exfat now, right?

Post by **bigpup** » Wed Oct 28, 2020 5:43 pm

Have you gotten a new one that is?

All I have gotten are still fat32 format.

m1k3 · Post by **m1k3** » Wed Oct 28, 2020 8:48 pm

bigpup wrote: ↑Wed Oct 28, 2020 5:43 pm Have you gotten a new one that is?

Yeah I just got a 128 GB Samsung FIT recently that was exfat. I ended up creating 3 partitions on it and kept one of them exfat.

Uten · Post by **Uten** » Sat Dec 05, 2020 3:30 am

2TB+ ssd is tempting. I do not think I will have fat32 on the entire disk.

s243a · Post by **s243a** » Sat Dec 05, 2020 5:48 am

There seems to be a caveat:

To maintain the greatest compatibility possible with existing programs, networks, and device drivers, FAT32 was implemented with as little change as possible to the existing Windows architecture, internal data structures, Application Programming Interfaces (APIs), and on-disk format.
...
Most programs will be unaffected by these changes. Existing tools and drivers should continue to work on FAT32 drives. However, MS-DOS block device drivers (for example, Aspidisk.sys) and disk tools will need to be revised to support FAT32 drives.
...
NOTE: Although the FAT32 file system supports hard disks up to 2 terabytes in size, some hard disks may not be able to contain bootable partitions that are larger than 7.8 GB because of limitations in your computer's basic input/output system (BIOS) INT13 interface. Please contact your hardware manufacturer to determine if your computer's BIOS supports the updated INT13 extensions.

https://support.microsoft.com/en-ca/hel ... ile-system

s243a · Post by **s243a** » Sat Dec 05, 2020 6:04 am

This also seems relevant:

The optimum cluster size for a large FAT32 partition depends on the number of clusters required to fill the entire partition. By definition, larger FAT32 partitions can handle larger cluster sizes, but note that the larger the cluster size the more space is wasted. If your FAT32 partition has a cluster size of 32KB, a file with a logical size of just 1 byte will still have a physical size of 32KB, effectively wasting 31KB of storage space. Similarly, a file with a logical size of 33KB -- 1 byte more than the cluster size -- will have a physical size of 64KB.

https://www.techwalla.com/articles/what ... partitions

The FAT32 boot sector uses a 32-bit field for the sector count, limiting the maximal FAT32 volume size to 2 tebibytes (approximately 2.2 terabytes) with a sector size of 512 bytes. The maximum FAT32 volume size is 16 TiB (approximately 17.6 TB) with a sector size of 4,096 bytes.[38][39] Windows operating systems through Windows 10 create new FAT32 volumes only up to 32 GB in size, however.

https://en.wikipedia.org/w/index.php?ti ... imal_Sizes

A cluster is made up of one or more sectors so a cluster can't be smaller than a sector. That means on a 2.2 terabyte drive each file will take at least 512 bytes:

Optimum cluster size depends on the partition size. ... Under the FAT32 file system, each partition is divided in clusters, each identified by a 32-bit number, or a series of 32 binary digits, or "bits." Each cluster consists of one or more smaller units, known as sectors, depending on the size of the partition.

https://www.techwalla.com/articles/what ... partitions

If one is doing cloud computing this is typically less relevant as cloud computing typically uses larger files. A workaround might be to use some kind of virtual file system where a file appears as a directory.

mistfire · Post by **mistfire** » Fri Dec 31, 2021 10:22 am

According to Dave Plummer one of the former devs of Microsoft. 32Gb is the max partition size for FAT32 and he set it as max partition limit.

Also FAT32 has huge cluster slack for larger drives. The drive space was underutilized due to cluster slacks.

More details on his YouTube Channel: Dave's Garage

Puppy Linux Discussion Forum