Slow performance after upgrade from v4 to v5

J

JoaoG

Bit poster
Hi,

I have recently upgraded from Parallels v4 to v5 and I am experience a significant loss of performance.
I have a windows vista VM running on a Macbook tablet (a Axiotron modbook) that I imported from v4 to v5.
I am running Snow Leopard and the latest build of Parallels.

My major problem seems to be with the graphics. When I write on the tablet (windows journal) the CPU usage quickly reaches 100% and the writing becomes very slow. The process that uses the CPU is prl_vm_app which I believe is the main application. In v4, it was working fine only slowing down at times (this is why I upgraded but the performance in v5 is dreadful).

I can get a similar behavior just by moving around the windows in the VM machine. The windows move slowly, leaving a shadow and the CPU goes to 100% usage.

I only use this machine to write lecture notes and this is a killer for me.
I have two questions:
1) Any guesses on why the graphical performance is so much worse in v5?
BTW, I have increased the VM machine graphical memory to 256 MB, and the memory to 3 GB (my computer has total of 6 GB) but didn't make a difference.

2) Is it possible to downgrade to v4 and import the VM back to v4?

Thanks,
 
Reduce the VM's memory to 1 GB or even less (I'm running Windows 7 on a 832 MB VM). Reduce the VM's graphics memory to 128 MB if possible (it may tell you that it needs 256 MB in which case leave it at 256 MB). Optimize for Mac OS X applications. Enable the Adaptive Hypervisor.

In my experience slowdowns happen because the VM is using a lot of memory and the Mac starts to do some serious swapping. Too little memory to the VM -> Windows starts swapping, too much VM memory -> the Mac starts swapping. So you need to find the right balance which is around 1 GB, maybe a bit more, maybe a bit less, depending on your Mac's specifications.

Good luck.
 
Thanks for the reply Shaddam.

I will try but I suspect that is not the problem because my macbook has 6 GB of memory, and it seldom gets fully used.
Initially, I had the VM with the configuration of 1GB of memory and 128 MB of graphics memory (and it did complain) and I still had the problem.
I don' think I have ever tried the other settings.
 
A weird fix to the problem

I have tried the fixes proposed above but they didn't work.
Tried many different configurations and still got slow performance.

Then, I found out the most bizarre thing.
I am mostly using Windows Journal. Once I start it, I can write on it at a reasonable speed without major problems.
The VM cpu usage gets up to 50% but that is it.
The problem is once I scroll the Windows Journal window. At that point, the performance becomes very slow.
Each time I use the pen to write the VM cpu usage increases to 100% and the writing becomes painfully slow and error prone. That keeps happening no matter how long I wait. Each operation makes the VM load go to a maximum.

Now, the weird fix.
It turns out that if I maximize the window of Windows Journal. Everything gets back to normal performance.
I am back to write without problems and the CPU usage drops to 50%. Even if I make the window smaller again or
if I scroll the window again. No matter what the problem goes away.

So, this seems to be some bug with the way the VM is handling the Wacom tablet.
I have not installed a driver in the VM so this is done through the host OS.

I have repeated this a few times with always the same results.
This is quite annoying but not a deal breaker. Now, Parallels v4 was working just fine. So, this effect has to be
due to some modification introduced in v5.

BTW, is there a way of getting support from Parallels or do we have to pay for everything?
I tried to open a ticket but failed.

-Joao
 
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