Hi, Alex King wrote: > I've installed a large disk in a new machine and loaded Debian (bookworm) on > it, but it's showing as limited to 2TB when the disk should be larger.
> root@fj2:/home/installer# smartctl -i /dev/sdb > [...] > User Capacity: 8,001,563,222,016 bytes [8.00 TB] > Sector Sizes: 512 bytes logical, 4096 bytes physical > root@fj2:/home/installer# cat /proc/partitions > major minor #blocks name > [...] > 8 16 2147483647 sdb Observation: 2147483647 = 2 exp 31 - 1 This could mean that the kernel bonks at a 31-bit limit. > root@fj2:/home/installer# cat /proc/version > Linux version 6.1.0-29-amd64 [...] But where would an amd64 kernel have such an ancient limitation ? > root@fj2:/home/installer# gdisk -l /dev/sdb > [...] > Disk /dev/sdb: 4294967294 sectors, 2.0 TiB > [...] > Sector size (logical/physical): 512/512 bytes This agrees to /proc/partitions. man proc_partitions says that it counts blocks of 1024 bytes. 4294967294 / 2 = 2147483647 Could there be confusion about the physical block size ? Probably not: The byte count resulting from block count multiplied by the physical block size 4096 as reported by smartctl does not match the reported "User Capacity" of smartctl: 2147483647 * 4096 = 8,796,093,018,112 That's higher than the smartctl value by nearly 10 percent, which makes it rather improbable as miscalculation suspect. So there remains only a simple 31-bit ceiling as suspect. It's not a 32-bit rollover where the result remainder of this division would have to be near to 0 , 1/2 or 1: 8001563222016 / 512 / 4294967296 = 7.277379356324673 Have a nice day :) Thomas
