Ticket #5169 (closed defect: fixed)
Bandwith from Host to Guest limited by the real ethernet mounted on host.
Reported by: | gionn | Owned by: | |
---|---|---|---|
Priority: | major | Component: | network |
Version: | VirtualBox 3.0.6 | Keywords: | |
Cc: | Guest type: | Linux | |
Host type: | Linux |
Description (last modified by frank) (diff)
virtualbox-ose 3.0.6-dfsg-1~bpo50+1 (debian lenny-backports)
I caught a behavior that I wasn't expecting
I have a Debian Lenny amd64 host with a gigabit network card but, unfortunately, attached to a 10/100 switch: 02:00.0 Ethernet controller: Attansic Technology Corp. L1 Gigabit Ethernet Adapter (rev b0)
I setup a Debian Lenny i386 guest with a gigabit network card: 00:11.0 Ethernet controller: Intel Corporation 82545EM Gigabit Ethernet Controller (Copper) (rev 02)
I was hoping that between host and guest, i will get full gigabit speed, but instead, I've host outgoing bandwidth limited by *real* speed.
Here the output of two iperf sessions:
Host -> Guest
[ 4] local 192.168.1.2 port 5001 connected with 192.168.1.10 port 54853 [ ID] Interval Transfer Bandwidth [ 4] 0.0-10.1 sec 114 MBytes 94.1 Mbits/sec [ 5] local 192.168.1.2 port 5001 connected with 192.168.1.10 port 54854 [ 5] 0.0-10.2 sec 114 MBytes 94.1 Mbits/sec [ 4] local 192.168.1.2 port 5001 connected with 192.168.1.10 port 54856 [ 4] 0.0-10.2 sec 114 MBytes 94.1 Mbits/sec
Guest -> Host
[ 4] local 192.168.1.10 port 5001 connected with 192.168.1.2 port 46946 [ ID] Interval Transfer Bandwidth [ 4] 0.0-10.0 sec 412 MBytes 345 Mbits/sec [ 5] local 192.168.1.10 port 5001 connected with 192.168.1.2 port 46947 [ 5] 0.0-10.0 sec 402 MBytes 337 Mbits/sec [ 4] local 192.168.1.10 port 5001 connected with 192.168.1.2 port 46948 [ 4] 0.0-10.0 sec 382 MBytes 320 Mbits/sec
So, it's the outgoing data from host to guest passed to the wire before getting into the guest? Is this an expected behaviour? Should I use a host-only network for having full transfer speeds?
What kind of network did you use to check this speed? Bridged? And which ethernet device emulation did you use for the guest? PCNet is probably a bit slower than E1000. Indeed you could try if host-only networking makes a difference.
Apart from this I can assure you that the network speed between guest and host is not limited by VBox nor by the network the host is attached.