A question about showing disk space

thomas2004ch · 10-16-2009, 02:19 AM

I use df -h to list the used disk and get followings:

Code:

[root@s003ap02-test ~]# df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/mapper/vg_root-lv_root
                      3.0G  2.3G  599M  80% /
/dev/sda1              99M   15M   80M  16% /boot
none                  3.0G     0  3.0G   0% /dev/shm
/dev/mapper/vg_root-lv_home
                      496M  381M   90M  81% /home
/dev/mapper/vg_root-lv_opt
                      7.9G  3.3G  4.3G  44% /opt
/dev/mapper/vg_root-lv_tmp
                      496M   73M  398M  16% /tmp
/dev/mapper/vg_root-lv_var
                      2.0G  1.1G  826M  57% /var
[root@s003ap02-test ~]#

One can see the /home uses 381 MB space.

As I try to list the detail I get followings:

Code:

[root@s003ap02-test ~]# du -sh /home/*
8.0K    /home/a5xcn81
8.0K    /home/a5xd8t0
8.0K    /home/a5xdea1
8.0K    /home/a5xjkh0
8.0K    /home/a5xkb41
8.0K    /home/a5xnhp0
8.0K    /home/a5xoy41
194M    /home/a5xsuuser
8.0K    /home/a5xx2u1
371K    /home/documaker
5.0K    /home/idcext2
12K     /home/lost+found
[root@s003ap02-test ~]#

I can't see the summe is 381 MB.

Someone knows why?

rizhun · 10-16-2009, 03:52 AM

Hi thomas2004ch,

Try the command:

Code:

$ du -shc /home

The glob might be causing you problems.

xeleema · 10-16-2009, 03:52 AM

Okay, you're "Reserved Blocks Percentage" might be a wee bit too high on that filesystem.
Back in the days of old, when disks were smaller, the default behavior for mkfs.ext2 and mkfs.ext3 was to set a "Reserved Blocks Percentage" to 5%.

Traditionally, this is so root-owned processes can still write space when bad little users processes max-out filesystems.

To see how many blocks are currently marked as reserved on an ext2 or ext3 filesystem, run the following command;

dumpe2fs /dev/mapper/vg00-lv_home | grep -i "reserved block count"

That'll show you how many blocks are restricted. Multiply that by how big your actual blocks are, and you'll know what percentage of your filesystem is restricted to root.

Keep in mind, your block size can be set when you initially use mkfs.ext2 and mkfs.ext3 to create a filesystem, as can the "reserved block count".

To change the "Reserved Block Count" on an existing ext2 and ext3, run the following command;

tune2fs -m 1 /dev/mapper/vg00-lv_home

Then do a "df -h" and see if that straightens things out.

thomas2004ch · 10-20-2009, 03:30 AM

Quote:

Originally Posted by rizhun

Hi thomas2004ch,

Try the command:

Code:

$ du -shc /home

The glob might be causing you problems.

This doesn't help a lot.