virtualbox.org

Running VB 3.1.2

I'm running Windows 2003 server guests in headless mode on a single HP Xeon server running Ubuntu 8 and 9. Things work really well with 5 guests running and people connecting via Terminal Services. However I may need to add even more guests, so I been looking for ways to optimize the guest performance.

First thing I tried was to limit the color depth on the guests. If I tell the TS client to set the color depth to 16bit or even 8bits, the colors passed back to me are definitely limited but the windows guests may actually still be running in 32bit mode.

The point is to limit the work the guest CPU is doing to display graphics so that if someone opens Firefox to some site with lots of stupid animations or something the guest doesn't bog down that much. The way VB seems to work, is to limit the colors sent to the client (which saves bandwidth) but doesn't stop the guests from doing 32bit graphics. This doesn't do me any good since I have plenty of bandwidth, what I need is to have the the guests do less work displaying graphics.

Obviously VB can tell the windows guest to set the resolution to whatever you set it to in the TS client options, why not the color depth? What am I missing here?


Thanks

What you are missing is that standard RDP will only do color dept for the client connected, if that is 16bit then no more then 16bit is handled, unless you are talking about vRDP, thats a different matter. RDP 24bit mode does not need much processor power, neither does 32bit, the slowness you might have is LAN/WAN related. vRDP however, is resource hungry.

vbox4me2 wrote:What you are missing is that standard RDP will only do color dept for the client connected, if that is 16bit then no more then 16bit is handled

I'm not sure what you mean by "handled". However the main reason for my post is not to debate the effect of color depth on performance, although it's more significant than you think.

The point is that using TS to connect to a VB windows guest is not the same thing as using TS to connect to a physical windows box. Turns out, a VB windows guest doesn't see the connection as being a RDP connection at all. This can be confirmed by running qwinsta in a cmd window. It shows no RDP connections active, it does show a console active though. Therefore none of the settings the admin makes with tscc.msc or gpedit or regedit have any effect on someone connecting via TS. As well, none of the options you set with the TS client have any effect at all except for resolution and even that is done by some other mysterious means, not the RDP protocol.

So unless there is something in VB that can be done like setextradata <extradataitem>, then using rdesktop or windows TS with VB windows guests is uncontrollable. And there are a lot of TS options besides color depth that people expect to work.

Regards.

See the vRDP and RDP explanations in the forum FAQ. I can easely run 4 TS's with each 100 clients on one quad core vbox Host.