I have narrowed down a performance problem in my Ubuntu guest on a Win7 VirtualBox host to the network, after comparing and equalising everything else to do with my slow-running Java app with a colleague who runs the same app under Win7.
I set up Ubuntu 12.04 in VirtualBox on the Win7 machine I was allocated on my new project. I am running Java, Eclipse, Tomcat to develop a large data-intensive application and this app literally runs at half the speed of my colleague's identical machine.
Is there a ping test I can do or some other network diagnostic test to flag up any problems? I will accept any answer that will just get me moving forward - I don't expect anyone to come up with a blinding solution for the issue.
To give some background, the network performance is confusing.
Running a network speed test to my colleague's machine with iperf shows speeds of 6 Mb/s from my Ubuntu guest, and 90 Mb/s from the win7 host.
Large downloads, e.g. the Java SDK, come down at about 1.2 MB/s on both the guest and the host.
Pings are sub-1ms on the host, but 1.5ms on the guest.
I also did a broadband speed test, and got 10Mb/s download speed on both, but the host has an upload speed of 10Mb/s but the guest only uploads at 3Mb/s.
I've been trying to diagnose any MTU problems with ping -M do to identify any kind of packet fragmentation problem but it's progressing very slow because I don't have much experience in this area.
From what I read on other people's networking issues with VB and Linux guests on Win7 hosts, I should be able to get the speed on the guest up to the same level as the host.
I installed a fresh VM with Ubuntu again to see if I'd foobar'd it somehow, but I'm getting the same readings with iperf on the virgin installation.
My setup is:
Adapter 1: Intel PRO/1000 MT Desktop (NAT)
Adapter 2: ditto (host-only adapter)
eth0 Link encap:Ethernet HWaddr 08:00:27:0b:76:bf inet addr:10.0.2.15 Bcast:10.0.2.255 Mask:255.255.255.0 inet6 addr: fe80::a00:27ff:fe0b:76bf/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:86236 errors:0 dropped:0 overruns:0 frame:0 TX packets:49369 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:69163946 (69.1 MB) TX bytes:3530535 (3.5 MB) eth2 Link encap:Ethernet HWaddr 08:00:27:a3:26:b8 inet addr:192.168.56.101 Bcast:192.168.56.255 Mask:255.255.255.0 inet6 addr: fe80::a00:27ff:fea3:26b8/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:59 errors:0 dropped:0 overruns:0 frame:0 TX packets:57 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:9148 (9.1 KB) TX bytes:7648 (7.6 KB) lo Link encap:Local Loopback inet addr:127.0.0.1 Mask:255.0.0.0 inet6 addr: ::1/128 Scope:Host UP LOOPBACK RUNNING MTU:16436 Metric:1 RX packets:701 errors:0 dropped:0 overruns:0 frame:0 TX packets:701 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:66321 (66.3 KB) TX bytes:66321 (66.3 KB)