Detect block size for quota in Linux
- by Chen Levy
The limit placed on disk quota in Linux is counted in blocks. However, I found no reliable way to determine the block size. Tutorials I found refer to block size as 512 bytes, and sometimes as 1024 bytes.
I got confused reading a post on LinuxForum.org for what a block size really means. So I tried to find that meaning in the context of quota.
I found a "Determine the block size on hard disk filesystem for disk quota" tip on NixCraft, that suggested the command:
dumpe2fs /dev/sdXN | grep -i 'Block size'
or
blockdev --getbsz /dev/sdXN
But on my system those commands returned 4096, and when I checked the real quota block size on the same system, I got a block size of 1024 bytes.
Is there a scriptable way to determine the quota block size on a device, short of creating a known sized file, and checking it's quota usage?