On Thu, 2004-12-09 at 03:42 -0500, Gene Heskett wrote: > Greetings; > > I need a bit of help from the ext3 filesystem folks I think. I'm > haveing a comprehension problem here. A snip from a df report: > > /dev/hdd3 176100712 165509176 26340 100.3% /amandatapes > > >From the above, there is about 10GB on the missing list! Amanda just > bailed out early because the disk was full, while the 2 figures on > the left claimed there should have been somewhere between 10GB and > 11GB of space left, not the 26 megs shown above. > > The output of a du . on that partition, before I ran the amflush, was > 165509176 bytes total used out of 176100712 that df claimed it has > for a total, both in 1024 byte kilobytes. > > So my question is: Where is the math broken? Both du and df, or my > head? > > Surely there cannot be 10+GB tied up in inodes and journals? > Math is not broken. The system automatically reserves a portion of the partition that is usable only by root, and any user space application will see the partition as 100% when it reaches this level. Without this reserved space, when a partition becomes 100% full it would not even accessible by root and thus the partition data could be lost completely. IIRC the number used to be 10% reserved, 90% user back when drives were a lot smaller. That may have changed but I do not know the actual number now. The available above and the difference in numbers indicate it still might be the original 10% reserved space that got you.
