Cut'n'paste from a tutorial I'm writing right now:
Check with lsof if there are any very large files that are already deleted but are still open by some processes.
# df -h . Filesystem Size Used Avail Use% Mounted on /dev/md0 194M 32M 153M 18% /boot # dd if=/dev/zero of=testfile bs=1024000 count=50 50+0 records in 50+0 records out 51200000 bytes (51 MB) copied, 0.370919 s, 138 MB/s # df -h . Filesystem Size Used Avail Use% Mounted on /dev/md0 194M 81M 104M 44% /boot # vi testfile
<wait till vi comes up, then crtl-z and bg the process>
# rm testfile # df -h . Filesystem Size Used Avail Use% Mounted on /dev/md0 194M 81M 104M 44% /boot
< quit vi>
# df -h . Filesystem Size Used Avail Use% Mounted on /dev/md0 194M 32M 153M 18% /boot
Also verify that your fs doesn't have a insane root reserved space set. # df -h . Filesystem Size Used Avail Use% Mounted on /dev/md0 194M 32M 153M 18% /boot # tune2fs -m 50 /dev/md0 tune2fs 1.41.4 (27-Jan-2009) Setting reserved blocks percentage to 50% (102368 blocks) # df -h . Filesystem Size Used Avail Use% Mounted on /dev/md0 194M 32M 63M 34% /boot
THere are of course other reasons but those two are a common problem.
Peter.
On Wednesday 30 September 2009 16:59:25 Ryan Pugatch wrote:
Hi all,
Curious issue.. looking in to how much disk space is being used on a machine (CentOS 5.3). When I compare the output of du vs df, I am seeing a 12GB difference with du saying 8G used and df saying 20G used.
# du -hcx / 8.0G total
# df -h / Filesystem Size Used Avail Use% Mounted on /dev/xvda3 22G 20G 637M 97% /
I recognize that in most cases du and df are not going to report the same but I am concerned about having a 12GB disparity. Does anyone have any thoughts about this or reason as to why there is a big difference? I have read a few articles online about it and none have really shown such a large difference.
Thanks
Ryan Pugatch Systems Administrator, TripAdvisor _______________________________________________ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos