System configuration:
Virtualbox 1.5.6, 64-bit binary packages on Ubuntu 7.10 host system.
Guest system: either Windows2000 or WindowsXP with guest additions installed.
Remote desktop connection via rdesktop-vrdp from a linux client connected via 1Gb Ethernet to server.
Problem description:
Running some applications that use vector graphics, like CAD systems, is extremely slow. Sometimes it takes several minutes (!!!) to refresh a screen which otherwise would take a split-second to redraw on a "real" PC. On WindowsXP the problem is so severe that sometimes VirtualBox just crashes. During redrawing of the screen the guest system seems totally stalled and unresponsive.
I've experienced this problem with "Zuken CadStar? express" and running a simulation in Octave with FEMM (The simulation is blazing fast, but redrawing the mesh on screen can take up to 3 minutes!).
Additional information:
Running VirtualBox as X-windows client instead of using VRDP, doen't make much of a difference, it is still horribly slow. Doing the test on VMWare-player, it is fast, sometimes about 20-100 times faster that in VirtualBox.
Ethernet network load also doesn't make any difference.
The speed (or slowliness) varies widely for no apparent reason. Sometimes it is just slow, and sometimes it is very slow. It seems as if drawing time increases exponentially with the complexity of the object that is being drawn, that means that simple drawings most of the time render quickly, whereas more complex drawings go in "bursts", slowing to a crawl somewhere in the middle. It becomes so slow, that you can count the indivitual lines being drawn on screen.
All other applications (that do no intense vector drawing on screen) run fine at normal speed, interaction is snappy and even transition effects on menus are quite workable.
