df bigger than ls?

[Brian Candler]

On Wed, Mar 07, 2012 at 03:54:39PM +0000, Brian Candler wrote:
> core.size = 1085407232
> core.nblocks = 262370

core.nblocks is correct here: space used = 262370 * 4 = 1049480 KB

(If I add up all the non-hole extents I get 2098944 blocks = 1049472 KB
so there are two extra blocks of something)

This begs the question of where stat() is getting its info from?

Ah... but I've found that after unmounting and remounting the filesystem
(which I had to do for xfs_db), du and stat report the correct info.

In fact, dropping the inode caches is sufficient to fix the problem:

root at storage1:~# du -h /disk*/scratch2/work/PRSRA1/PRSRA1.1.0.bff
2.0G	/disk10/scratch2/work/PRSRA1/PRSRA1.1.0.bff
2.0G	/disk11/scratch2/work/PRSRA1/PRSRA1.1.0.bff
2.0G	/disk12/scratch2/work/PRSRA1/PRSRA1.1.0.bff
1.1G	/disk1/scratch2/work/PRSRA1/PRSRA1.1.0.bff
1.1G	/disk2/scratch2/work/PRSRA1/PRSRA1.1.0.bff
2.0G	/disk3/scratch2/work/PRSRA1/PRSRA1.1.0.bff
2.0G	/disk4/scratch2/work/PRSRA1/PRSRA1.1.0.bff
2.0G	/disk5/scratch2/work/PRSRA1/PRSRA1.1.0.bff
2.0G	/disk6/scratch2/work/PRSRA1/PRSRA1.1.0.bff
2.0G	/disk7/scratch2/work/PRSRA1/PRSRA1.1.0.bff
2.0G	/disk8/scratch2/work/PRSRA1/PRSRA1.1.0.bff
2.0G	/disk9/scratch2/work/PRSRA1/PRSRA1.1.0.bff
root at storage1:~# echo 3 >/proc/sys/vm/drop_caches 
root at storage1:~# du -h /disk*/scratch2/work/PRSRA1/PRSRA1.1.0.bff
1.1G	/disk10/scratch2/work/PRSRA1/PRSRA1.1.0.bff
1.1G	/disk11/scratch2/work/PRSRA1/PRSRA1.1.0.bff
1.1G	/disk12/scratch2/work/PRSRA1/PRSRA1.1.0.bff
1.1G	/disk1/scratch2/work/PRSRA1/PRSRA1.1.0.bff
1.1G	/disk2/scratch2/work/PRSRA1/PRSRA1.1.0.bff
1.1G	/disk3/scratch2/work/PRSRA1/PRSRA1.1.0.bff
1.1G	/disk4/scratch2/work/PRSRA1/PRSRA1.1.0.bff
1.1G	/disk5/scratch2/work/PRSRA1/PRSRA1.1.0.bff
1.1G	/disk6/scratch2/work/PRSRA1/PRSRA1.1.0.bff
1.1G	/disk7/scratch2/work/PRSRA1/PRSRA1.1.0.bff
1.1G	/disk8/scratch2/work/PRSRA1/PRSRA1.1.0.bff
1.1G	/disk9/scratch2/work/PRSRA1/PRSRA1.1.0.bff
root at storage1:~# 

Very odd, but not really a major problem other than the confusion it causes.

Regards,

Brian.