0
brain:/# df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/xvda1            9.2G  8.6G  151M  99% /
tmpfs                 136M     0  136M   0% /lib/init/rw
udev                   10M  560K  9.5M   6% /dev
tmpfs                 136M     0  136M   0% /dev/shm
/dev/mapper/bkp       5.8G  140M  5.4G   3% /mnt/bkp
brain:/# du -sh
du: cannot access `./proc/31128/task/31128/fd/4': No such file or directory
du: cannot access `./proc/31128/task/31128/fdinfo/4': No such file or directory
du: cannot access `./proc/31128/fd/4': No such file or directory
du: cannot access `./proc/31128/fdinfo/4': No such file or directory
2.6G    .

What gives? Why is only 151 mb available when only 2.6 out of 9.2 gigs are used? And why does it say 8.6 gigs are used when only 2.6 gigs are? 

(.virtualenv)user@brain:~$ cat /proc/version
Linux version 2.6.26-2-686-bigmem (Debian 2.6.26-26lenny1) (dannf@debian.org) (gcc version 4.1.3 20080704 (prerelease) (Debian 4.1.2-25)) #1 SMP Thu Nov 25 01:59:22 UTC 2010

running on Xen virtualization software.

Claudiu
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    See also http://serverfault.com/questions/132998/no-free-disk-space , including the surprise twist at the end (mounted another drive over the top of a directory that had files in it) – DerfK Mar 23 '11 at 18:47
  • @DerfK, this should definitely be an answer! :) – Andrew M. Mar 23 '11 at 18:55
  • ah nice, though the answers there dont apply (no NFS, and lsof doesnt show 6 gigs being used) – Claudiu Mar 23 '11 at 22:15

1 Answers1

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By default, 5% of the disk is reserved for root, this 5% is perhaps free but not available. You can verify that you have blocks reseved with tune2fs -l /dev/xvda1 ; you can change the amount reseved with tune2fs's -r, (see the tune2fs manpage)

stew
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