Network connection gets slow and irresponsive on the guest OS after a while

[gu99roax]

On a freshly booted virtual machine, the network connection on the guest OS is normal. But after letting e.g. a bittorrent client be active for a while, the internet connection gets very slow to respond for all applications in the guest OS. For example loading google.com or any other website in a web browser takes a long time, anti-virus software reports update problems. The speed of the data transfers on bittorrent client don't seem to be affected considerably but it occasionally loses connection with the trackers so it seems to be struggling as well. Responses to the ping command however, seem to be unaffected by this condition. It can also be worth noting that the bittorrent client is throttled so that it never uses the full bandwidth of the internet connection. It communicates with both the tcp and the udp protocols.

This is a non-issue on the host machine as well as other computers on the network sharing this internet connection (100Mbit fiberLAN). The sluggishness also affect accessing other machines on the local network (e.g. loading router admin page, accessing web pages on other computers on the local area network ...)

What is conspicuous is that the connection continues to sluggish and irresponsive even after the bittorrent client is shut down. The only way to recover the connection is to restart the virtual machine.

This issue occurs when using a NAT network connection as well as when using a Bridged Adapter as a network connection for the guest OS. The motherboard on the host computer has two network adapters so when I use a bridged adapter for the virtual machines I link it to one of them (rge1) which is separate from the network adapter used in the host OS (rge0).

[gu99roax]

This log is for running Win XP x64 as a guest OS in OpenSolaris using NAT for network connection.

[gu99roax]

This log is for running Win XP x64 as a guest in OpenSolaris using Bridged Adapter for network

[Frank Mehnert]

How good is this reproducible? Wild guess (just read some other reports): Does the same problem happen if you disable nested paging for that guest?

[gu99roax]

I don't understand what you mean with 'good'. I fail to see what's 'good' about it. This happens every time I have put a load on the network connection for a few minutes and it has never deviated from this regardless of the settings.

I have tried to run the machine with nested paging disabled but the guest os doesn't like it. After bootup the guest freezes and become unresponsive. I'll submit the logs from that.

[gu99roax]

Guest OS freezing when trying to run it with nested paging disabled

[gu99roax]

Another attempt of running the machine with nested paging disabled yielding the same freeze-up result

[gu99roax]

Just to clarify the nature of the freeze-up; the machine does not respond to input from the mouse, nor the keyboard. But the mouse pointer moves and has the form of a turning hourglass. I managed to make it respond to a CTRL+ALT+DEL insertion but I didn't manage to get beyond that dialogue window. The boot splash of a program that was starting at the point when the freeze-up occurred became stuck.

[Frank Mehnert]

Didn't suppose to talk about 'good' bugs but my question was rather how easy it is for you to reproduce the problem. So according to your answer, these connection problems are easy to reproduce (unfortunately not here). And not related to nested paging.

[gu99roax]

Whether the nested paging option does cause this or not is something I'm unable to verify since the guest OS hangs almost immediately after finished boot-up.

I have now tried to reproduce this problem on a Windows 7 x64 machine but failed. In that machine I get better performance in the torrent client than in the XP x64 machine and other software don't have any problems with network access even at transaction speeds around 5-6 MB/s.

I have also so far not experienced any freeze-ups in the storage pool as I do while accessing for example HD video over CIFS while seeding with uTorrent in the XP x64 machine.

However, I feel that I need to do further testing before I can reach a final verdict on this...

[aeichner]

Please reopen if still relevant with a recent VirtualBox release.