Bug 1001453

Truncating a file to a larger size and writing to it is a common used for image files used as a VM or additional disk, we should not be violating quota during such scenarios.

Also, one can create a sparse file of size more than the quota limit set on the directory. 
Problem happens, that in case of continuous append operation one can cross the quota limits. As the file size keeps goes beyond quota limit set.

eg.
1. set a quota limit of 1GB on a directory
2. create sparse file of size 2GB with this command,
   time dd if=/dev/zero of=f.1 bs=1 count=1 seek=2097152k
3. then try to append data to it, using the command,
   while [ 1 ]; do cmd=`echo "hello" >> f.1`; if [ "$(echo $cmd | awk '/Disk quota exceeded/')" ]; then    echo "quota limit reached"; fi


result is the file size goes beyond 1GB

and in the present case it is,
[root@rhsauto005 dir1-data]# ls -l /mnt/nfs-test/sparse-file-dir/
total 264
-rw-r--r--. 1 root root 2147749299 Oct 25 08:01 f.1

i.e. around 2GB

Moving the known issues to Doc team, to be documented in release notes for U1

Moving the known issues to Doc team, to be documented in release notes for U1

Moving the known issues to Doc team, to be documented in release notes for U1

I;ve documented this as a known issue in the Big Bend Update 1 Release Notes. Here is the link:

http://documentation-devel.engineering.redhat.com/docs/en-US/Red_Hat_Storage/2.1/html/2.1_Update_1_Release_Notes/chap-Documentation-2.1_Update_1_Release_Notes-Known_Issues.html

'ls -l can report the size of the sparse file which is pre-allocated'
To get the actual disk size of the file, please use 'du -ksh filename'

Closing as NOTABUG

In gluster version 'glusterfs 3.4rhs' du command gives the actual disk spaces used.

Here is the test output:

root@rh1:/mnt # gluster --version
glusterfs 3.4rhs built on Jan 13 2015 17:25:03
Repository revision: git://git.gluster.com/glusterfs.git
Copyright (c) 2006-2011 Gluster Inc. <http://www.gluster.com>
GlusterFS comes with ABSOLUTELY NO WARRANTY.
You may redistribute copies of GlusterFS under the terms of the GNU General Public License.

Testcase-2:

root@rh1:/mnt # g v quota vol1 limit-usage / 10MB
volume quota : success

root@rh1:/mnt # g v quota vol1 hard-timeout 0
volume quota : success

root@rh1:/mnt # g v quota vol1 soft-timeout 0
volume quota : success

root@rh1:/mnt # dd if=/dev/zero of=1 bs=1024k count=10
10+0 records in
10+0 records out
10485760 bytes (10 MB) copied, 0.110432 s, 95.0 MB/s

root@rh1:/mnt # gluster v quota vol1 list
                  Path                   Hard-limit Soft-limit   Used  Available  Soft-limit exceeded? Hard-limit exceeded?
---------------------------------------------------------------------------------------------------------------------------
/                                         10.0MB       80%      10.0MB  0Bytes             Yes                  Yes


root@rh1:/mnt # truncate --size 10GB 1

root@rh1:/mnt # for i in {1..100}; do cat /var/log/messages >> 1 ; done
cat: write error: Disk quota exceeded
cat: write error: Disk quota exceeded
cat: write error: Disk quota exceeded


root@rh1:/mnt # ls -l 1
-rw-r--r--. 1 root root 10000000000 Jan 13 17:30 1

root@rh1:/mnt # du -ks 1
10244	1




Testcase-2:
root@rh1:/mnt # time dd if=/dev/zero of=1 bs=1 count=1 seek=2097152k
1+0 records in
1+0 records out
1 byte (1 B) copied, 0.00551734 s, 0.2 kB/s

real	0m0.096s
user	0m0.002s
sys	0m0.004s

root@rh1:/mnt # ls -l 1
-rw-r--r--. 1 root root 2147483649 Jan 13 17:33 1

root@rh1:/mnt # du -sh 1
8.0K	1