vivid: ext4 over LVM over mdadm RAID6 files do not get removed immediately

hi,

I run vdr with video directory on a separate partition with ext4, over LVM, over mdadm RAID6. The same partition is also exported via NFS

A couple of nights ago, space run out of the partition, and VDR deleted a recording. The space was not freed, so VDR removed the next recording, and so on. The disk was not freed until a reboot the next morning.

The questions:
- Are there any parameters on the FS, LVM, or RAID level, that has an effect here?
- Is NFS server reserving the deleted files (reference counting preventing the deletion); is there an option for that, or would that be something that happens during an error with NFS-server-client communication?

Some parameters:

dumpe2fs 1.42.12 (29-Aug-2014)
Filesystem volume name: <none>
Last mounted on: /srv/vdr/video.00
Filesystem UUID: 0a8f2b37-4a27-4a06-b236-971af0cf1907
Filesystem magic number: 0xEF53
Filesystem revision #: 1 (dynamic)
Filesystem features: has_journal ext_attr resize_inode dir_index filetype needs_recovery extent sparse_super large_file uninit_bg
Filesystem flags: signed_directory_hash
Default mount options: (none)
Filesystem state: clean
Errors behavior: Continue
Filesystem OS type: Linux
Inode count: 256114688
Block count: 1024458752
Reserved block count: 51222927
Free blocks: 916436860
Free inodes: 256101715
First block: 0
Block size: 4096
Fragment size: 4096
Reserved GDT blocks: 779
Blocks per group: 32768
Fragments per group: 32768
Inodes per group: 8192
Inode blocks per group: 512
RAID stride: 128
RAID stripe width: 384
Filesystem created: Mon Sep 21 21:47:18 2009
Last mount time: Sun May 3 14:06:40 2015
Last write time: Sun May 3 14:06:40 2015
Mount count: 49
Maximum mount count: 200
Last checked: Thu Apr 16 06:08:46 2015
Check interval: 17280000 (6 months, 2 weeks, 6 days)
Next check after: Mon Nov 2 05:08:46 2015
Lifetime writes: 14 TB
Reserved blocks uid: 0 (user root)
Reserved blocks gid: 0 (group root)
First inode: 11
Inode size: 256
Required extra isize: 28
Desired extra isize: 28
Journal inode: 8
Default directory hash: half_md4
Directory Hash Seed: ef0f022c-b41f-4a14-9957-e0f69e74987b
Journal backup: inode blocks
Journal features: journal_incompat_revoke
Journal size: 128M
Journal length: 32768
Journal sequence: 0x00d04442
Journal start: 8264

lvdisplay /dev/mapper/xpcvg-video
  --- Logical volume ---
  LV Path /dev/xpcvg/video
  LV Name video
  VG Name xpcvg
  LV UUID 5Rta2B-ErNZ-WQQU-6K6m-2sVO-p1xl-GBTTN2
  LV Write Access read/write
  LV Creation host, time ,
  LV Status available
  # open 1
  LV Size 3,82 TiB
  Current LE 1000448
  Segments 2
  Allocation inherit
  Read ahead sectors auto
  - currently set to 6144
  Block device 252:1

cat /proc/fs/ext4/dm-2/options
rw
block_validity
delalloc
barrier
user_xattr
acl
resuid=0
resgid=0
errors=continue
commit=5
min_batch_time=0
max_batch_time=15000
stripe=384
data=ordered
inode_readahead_blks=32
init_itable=10
max_dir_size_kb=0