/home user directory limit

[aleksnikolic]

Hi guys,

As I am new to Fedora I come across some weird things. During the installation I allocated 600GB logical volume to my /home. I created just one user whose folder /home/user is now showing 100% even though /home has plenty of space. No quota set up.

Here's my fstab file.

[root@aleks network-scripts]# cat /etc/fstab

#
# /etc/fstab
# Created by anaconda on Sat Oct 27 15:32:44 2012
#
# Accessible filesystems, by reference, are maintained under '/dev/disk'
# See man pages fstab(5), findfs(8), mount(8) and/or blkid(8) for more info
#
/dev/mapper/vg_aleks-lv_root / ext4 defaults 1 1
/dev/mapper/vg_aleks-lv_home /home ext4 defaults 1 2
/dev/mapper/vg_aleks-lv_therest /therest ext4 defaults 1 2
/dev/mapper/vg_aleks-lv_vmspace /vmspace ext4 defaults 1 2
/dev/mapper/vg_aleks-lv_swap swap swap defaults 0 0

[root@aleks network-scripts]# df -h
Filesystem Size Used Avail Use% Mounted on
rootfs 97G 13G 80G 14% /
devtmpfs 7.8G 0 7.8G 0% /dev
tmpfs 7.8G 804K 7.8G 1% /dev/shm
tmpfs 7.8G 1.9M 7.8G 1% /run
/dev/mapper/vg_aleks-lv_root 97G 13G 80G 14% /
tmpfs 7.8G 0 7.8G 0% /sys/fs/cgroup
tmpfs 7.8G 0 7.8G 0% /media
/dev/mapper/vg_aleks-lv_home 577G 851M 547G 1% /home
/dev/mapper/vg_aleks-lv_vmspace 145G 2.1G 135G 2% /vmspace
/dev/mapper/vg_aleks-lv_therest 95G 188M 90G 1% /therest

But when I run Disk Usage utility it says that my user home folder is full and now I have a problem for example syncing my dropbox folder which is by default installed in /home/user folder. Every installation is taking too long since its writing something in /home/user. Disk LED is flashing solid light every time I try to install something.

Is there any default setting that I should be aware of? I thought that my /home/user folder could consume all /home partition.

[jpollard]

How many files are there? (df -i)

full is a relative term - by default, root as a reserved 10% and this can be altered (tune2fs). But you can also be full if all the inodes are taken. This means that no new files can be created, but does mean pre-existing files can be extended (as long as there are available blocks) or replaced/overwritten.

[aleksnikolic]

No problems with number of inodes.

[root@aleks network-scripts]# df -i
Filesystem Inodes IUsed IFree IUse% Mounted on
rootfs 6406144 138548 6267596 3% /
devtmpfs 175582 556 175026 1% /dev
tmpfs 179985 11 179974 1% /dev/shm
tmpfs 179985 651 179334 1% /run
/dev/mapper/vg_aleks-lv_root 6406144 138548 6267596 3% /
tmpfs 179985 12 179973 1% /sys/fs/cgroup
tmpfs 179985 1 179984 1% /media
/dev/mapper/vg_aleks-lv_home 38404096 1872 38402224 1% /home
/dev/mapper/vg_aleks-lv_vmspace 9601024 13 9601011 1% /vmspace
/dev/mapper/vg_aleks-lv_therest 6307840 11 6307829 1% /therest

Still IO performance is really poor. Syncing my dropbox folder (500M) is taking more than 2 hours even though my broadband connection is good enough (usually download 500M takes couple of minutes).

[stevea]

Originally Posted by jpollard

How many files are there? (df -i)

full is a relative term - by default, root as a reserved 10%

Minor nit. Used to be 10%, but its 5% now. There is no reserved ratio in the mke2fs.conf and so the default is 5% (see 'man mkfs.ext4'). Still way too much on a modern partition IMO, and the root idea is more than a little dated.

Originally Posted by aleksnikolic

Hi guys,

As I am new to Fedora I come across some weird things. During the installation I allocated 600GB logical volume to my /home. I created just one user whose folder /home/user is now showing 100% even though /home has plenty of space. No quota set up.

I see your ~600GB /home alright. But you are misinterpreting the 100% figure.

When you use the disk usage analyzer ('baobab' is the tool), to analyze a folder (not a file system) then it always shows the folder as 100% and shows the various folder contents as a percentage of the folder size. IOW it is telling you what fraction of the folder is used for various dirs and files (and the top dir is always 100%). It is NOT telling you the folder is full or that you can't add more files.

So baobab does two different things - it analyzes filesystem usage and it also can analyze folders (directories) usage. Use the 'Analyzer' tab to select.
To analyze filesystems, use the 'Edit->Preferences' to select mount points, then use the 'Analyzer->Scan_File_System'. When you do analyze filesystems it still shows the filesystem content as 100%, and shows each dir and file as a percent of the usage, not a percent of the total filesystem size, but a percentage of that used.

My personal opinion is that baobab is a tool of limited value, and it's main use is to show you where your disk space is getting used up. It helps give a visual picture of file usage by size.

'df' is a much better tool for verifying filesystem usage, but even then it takes a little judgement to understand.

[stevea@crucibulum Desktop]$ df
Filesystem            1K-blocks      Used Available Use% Mounted on
rootfs                 20642428   8743144  11689604  43% /
devtmpfs                3973772         0   3973772   0% /dev
tmpfs                   3984884       108   3984776   1% /dev/shm
tmpfs                   3984884      7732   3977152   1% /run
/dev/sda3              20642428   8743144  11689604  43% /
tmpfs                   3984884         0   3984884   0% /sys/fs/cgroup
tmpfs                   3984884         0   3984884   0% /media
/dev/sda4              83886080   4598304  75543152   6% /home
/dev/sda4              83886080   4598304  75543152   6% /home/stevea
hypoxylon:/sohocommon 516061568 306579584 183267584  63% /home/common

You might note that root is shown twice (as rootfs and as /dev/sda3) and that the two btrfs subvolumes mounted at /home and /home/stevea show duplicate info. The network share mounted at /home/common is also shown.


'du' is used for analyzing on a file-oriented basis

[stevea@crucibulum Desktop]$ du -sh ~
du: cannot read directory `/home/stevea/.config/nautilus-actions': Permission denied
4.8G /home/stevea

The error is due to a Gnomic problem.

[aleksnikolic]

Thanks Stevea,

I assumed that 100% usage of my home dir represents what you just described. Seems that my troubleshooting why installations is taking too long is going the wrong side. For example. I have just started the installation of Eclipse through GUI tool Add/Remove Software and it took at least 40 minutes to install it with all dependencies. The strange thing when I searched for package, ticked the box and hit apply button it took at least three minutes to get a dialog box to enter my password. In the meantime my HDD was really busy. Didn't have that experience with ubuntu before.

And beside that my machine is brand new one with i7 Quad Core CPU and 16GB of RAM.


Any ideas or document I should follow to optimize disk IO?