virtualbox.org

OK, seems like I am getting somewhere with this… I would like someone else to test this and report any findings.

I'm on OS X 10.8.5 host running a winXPsp3 guest with default settings (except from RAM set to 1GB), guest additions installed. Running in full-screen on my iMac (2560x1440).

Download and install Chrome, then access any webpage; next make chrome's window quite large, around 90% of the screen and try dragging the window in small circular moves.

In my setup, it moves in "slow motion", there is a huge lag in dragging the window, the window doesn't follow the cursor's speed, it falls behind, and keeps on moving after the cursor has stopped moving.

Here is a video of the effect itself. Should I also upload any debug information, or are the replicate instructions enough?

P.S. I also tried the above on win7 and the issue does not exist.

UPDATE:
There are also threads regarding the same lag under win7 guests: viewtopic.php?f=2&t=60238
This thread focuses on lad while using AutoCAD: viewtopic.php?f=2&t=36267

I tried it with WinXP SP3 and Win7. No problems with dragging the window. No lagging in the drawing. Windows 7 was a little bit "erratic" but I believe it's a different issue that has to do with the WDDM drivers.

There have been several reports regarding Chrome. From what I've gathered it's got to do something with its hardware (GPU) acceleration.

socratis,

It's not just Chrome that's producing such results; it's just more noticeable when using Chrome, that's why I am testing using it. It even happens when moving large windows explorer windows, even empty ones.

What's your host OS? Your monitor resolution? Did you try creating a new VM, or did you test it on an existing one? Seems strange the effect does not pop up under your config, since it's very easy to replicate it over here. Did you have a look on the video I've uploaded?

No sluggish window drags here. XP Pro SP3 (32bit) for both guest and host, VBox 4.3.6 and ditto for the GAs version. VM display size 1792x1312x32bpp. In addition to making sure the GAs are installed, you may want to pay particular attention that the color depth in your VM is the same as on the host, as that is a known cause of poor performance.

If it is only Chrome that is sluggish, you might try to change acceleration settings for Chrome with about:flags.

Host: MBPro 17', OSX 10.6.8, 1920x1200, AMD Radeon HD 6750M, 16GB RAM, VBox 4.3.6 with same ext. pack and GAs.

Guest: XP SP3, 768MB RAM, 4 CPUs, 128MB VRAM, 2D+3D enabled.

@jorgensen
Nope, it's not just Chrome as he stated, it's more general. mpack's suggestion may be on the correct path...

mpack wrote:In addition to making sure the GAs are installed, you may want to pay particular attention that the color depth in your VM is the same as on the host, as that is a known cause of poor performance.

Tried 16 and 24bit on the guest and the issue is still the same. My iMac has an ATI Radeon HD 4850, didn't find any reports regarding issues with this host GPU.

thanar wrote:Tried 16 and 24bit on the guest and the issue is still the same

Surely you can find out which is the correct value, rather than thrash around? In this day and age it would normally be 32bpp.

Of course it's 32bit, give me a break! I just switched to lower bit depths just to test it out!

Anyhow:
I created a new winXPsp3 VM on a DIFFERENT 27inch iMac (model 11,1) of the same specs (we got two of them over here) and same OS (10.8.5), again default VM settings (changed only VM RAM to 1GB), installed xp, installed additions, restarted, switched to full screen.

This time, I tested with IE, made window 90% of screen size and tried panning; the lag is the same as on the other iMac.

If you bring up Task Manager in the guest, does it show any particular Processes using lots of CPU? Something like Windows Update or Security Essentials or some AV software you may have loaded?

While dragging the window, "idle" stays at over 50%, while the application whose window is currently being dragged climbs up to a max 50%, looks like pretty expected to me. The issue shows up on IE as well, as well as while SCALING a window. It actually happens on ANY application window, as long as the window size is larger than 2000x1200 pixels. I bet it has to do with 2D acceleration, it just puzzles me how no-one has managed to replicate is, since it's so easy to do; well, as long as you have a large enough monitor, that is...

Just opened a related ticket on VBox's bug reporting system.

Just tested the issue using VB 4.3.8, still the same. I have uploaded a video on the issue for others to get a general idea and test it out.

Also, updated the original post with other similar threads I found on the forums, seems like the issue is not windowsXP-only, there are reports on the same behavior under win7 as well, it's just less noticeable under win7 because you can use more than one CPUs.

The ticket I opened more that a month ago has not been touched yet.