Opened 10 years ago
Closed 8 years ago
#12855 closed enhancement (obsolete)
Change to using raw disk access by default for USB mass storage devices
| Reported by: | Pedro Côrte-Real | Owned by: | |
|---|---|---|---|
| Component: | virtual disk | Version: | VirtualBox 4.3.8 |
| Keywords: | Cc: | ||
| Guest type: | other | Host type: | other |
Description
USB 2.0 support tends to be buggy and USB 3.0 doesn't exist yet. For mass storage devices a better option is to let the host device handle the USB side and then pass on the raw block device. Today when attaching a USB drive on a Windows 7 host to a Ubuntu 12.04 guest I got (on the guest):
$ sudo hdparm -t /dev/sdb
/dev/sdb:
Timing buffered disk reads: 10 MB in 3.46 seconds = 2.89 MB/sec
After fiddling with the command line and instead letting the Windows host do the USB and passing the raw disk to Ubuntu:
$ sudo hdparm -t /dev/sdb
/dev/sdb:
Timing buffered disk reads: 92 MB in 3.03 seconds = 30.41 MB/sec
This is the USB2.0 maximum. If the port supported USB3 (like the disk did) I'd get even higher speed.
This would make a much better default mode of operation if the GUI supported this mode natively and if VBox handled the plug/unplug gracefully. As it stands if you unplug the device the Linux guest just sees SATA errors and you need to reboot it to get the device back. It would make sense to make the virtual SATA controller support hotplug properly and use this for all USB mass storage devices.
Change History (2)
comment:1 by , 10 years ago
comment:2 by , 8 years ago
| Resolution: | → obsolete |
|---|---|
| Status: | new → closed |
USB 3 is supported since some time now and offers good performance for USB mass storage devices, closing as obsolete.
I know that the USB2 performance is still a problem. Working is going on to change that. as for SATA hotplug: This should actually work if you tell the guest to detach the medium. Use 'VBoxManage storageattach' for this.