Ticket #4651 (closed defect: duplicate)
DISK emulation ignore the flush() request for performance
|Reported by:||javaboyuk||Owned by:|
The VB disk emulations ignore the flush() request to the drives both RAW and file based.
This needs to be documented in the virtual disk section. A work arround for IDE seems to be available but is not documented:
VBoxManage setextradata VMNAME "VBoxInternal/Devices/piix3ide/0/LUN#[x]/Config/IgnoreFlush" 0
I don't see away to allow do this for SATA etc. and the options for IDE were talked about in the referenced link below.
This could lead to DATA LOSS (and filesystem loss) this is espically dangerous for Filesystems that are transcationally based eg ZFS. For the discusion on ZFS you might look at this http://www.opensolaris.org/jive/thread.jspa?threadID=108213&tstart=0 and this for the IDE discusion: http://forums.virtualbox.org/viewtopic.php?f=8&t=13661&start=0
(the IDE emulation also does this but, I believe, can have it disbaled with:VBoxManage setextradata VMNAME "VBoxInternal/Devices/piix3ide/0/LUN#[x]/Config/IgnoreFlush" 0 )