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I have a Dell Precision 490 workstation computer which I installed the latest version of Ubuntu Linux on. It has 8GB RAM, and Dual Xenon CPUs, so a total of four cores.

The problem is I give my VM machine, which is a Windows 7 Ultimate 4GB RAM, and 3 CPUs, and I receive poor network performance.

I made this machine because I wanted a Linux machine, and a Windows 7 machine which I can SFTP to, do some Apache PHP stuff, and also RDP to Windows and have access basically everywhere.

When I RDP to my machine it accepts my connection pretty slowly, and when I finally get in, I can only do easy tasks: browsing network shares with thumbnails takes forever, and if I accidentally open a webpage it takes a long time to refresh it just once.

What really takes the cake is that if I open MSN I basically just lose the connection and it tries to reconnect all the times. When I reconnect, I can see the screen drawing then stopping and I lose the connection again.

I have another computer which runs Windows 7 Ultimate on the same network. I run RDP on a different forwarded port, which has absolutely no issues on network performance, so what can I do in order to enhance the performance?

Here is a dump of uptime and TOP + various other stats if anyone can make anything out of it:

stian@stian-Precision-WorkStation-490:~$ uptime
 09:33:52 up 53 days, 10:07,  4 users,  load average: 1.08, 1.03, 1.05

top - 09:37:13 up 53 days, 10:10,  4 users,  load average: 10.76, 10.75, 5.15
Tasks: 197 total,   1 running, 193 sleeping,   0 stopped,   3 zombie
Cpu(s):  1.2%us, 12.2%sy,  0.0%ni, 86.2%id,  0.5%wa,  0.0%hi,  0.0%si,  0.0%st
Mem:   8191312k total,  7517992k used,   673320k free,   602844k buffers
Swap:  4190204k total,   226032k used,  3964172k free,   727896k cached

21557 stian     20   0 4533m 4.1g 4.0g S   47 52.0   2823:50 VBoxHeadless
21438 stian     20   0 1363m 1.1g 1.0g S    8 13.5   1152:47 VBoxHeadless
21447 stian     20   0  270m 7956 5376 S    0  0.1   9:05.58 VBoxSVC
21979 stian     20   0 21572 1440  992 R    0  0.0   0:00.06 top
    1 root      20   0 24184 1364  620 S    0  0.0   0:07.80 init
    2 root      20   0     0    0    0 S    0  0.0   0:32.86 kthreadd
    3 root      20   0     0    0    0 S    0  0.0   2:48.53 ksoftirqd/0
    6 root      RT   0     0    0    0 S    0  0.0   0:00.00 migration/0
    7 root      RT   0     0    0    0 S    0  0.0   0:00.00 migration/1
    9 root      20   0     0    0    0 S    0  0.0   1:03.46 ksoftirqd/1
   11 root      RT   0     0    0    0 S    0  0.0   0:00.00 migration/2
   13 root      20   0     0    0    0 S    0  0.0   1:30.90 ksoftirqd/2
   14 root      RT   0     0    0    0 S    0  0.0   0:00.00 migration/3

Windows Task manager

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Please state your question in the title, so that we won't have to read your entire post to get a grip on your question! – poplitea Dec 28 '11 at 8:51
It's in the second paragraph. Feel free to suggest an edit @poplitea – slhck Dec 28 '11 at 8:57
up vote 2 down vote accepted

There are a lot of variables here, such as

  1. is Ubuntu Linux for 32bit or 64bit architecture?
  2. is the VM fully- or para-virtualized?
  3. what type of network adapter you've configured for the VM
  4. what is network performance like on the Linux host?
  5. the Linux host has been up for 53 days. Is this the case for the other OS too? ;)

For a start try scaling back the VM memory and CPUs to, say 2GB and 1 CPU then test the network performance again.

Also, from the system resources output you provided it seems like the Linux host requires more swap space. You should probably add another 4GB (it can be a separate partition from your existing swap partition, or resize the existing space if you're comfortable with that)

It may be insightful to install another VM running a (different) 32bit OS and evaluate its performance

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