I was also having terrible CPU performace for all VMs until I did a little searching and guessing. While there is no specific "Server" Real-Time kernel (rt), I was able to get huge performance increases with Beta1 by using the one that is available.
I used the following commands to install it on my 7.10 server:
apt-get install linux-rt
apt-get install linux-headers-2.6.22-14-rt
I then edited /boot/grub/menu.lst to load it as the default. Once I rebooted and successfully reconfigured with vmware-config.pl, it was running great!
yes, thats the kernel I used too. guests are running much better now.
but still, the standard kernel is supported (modules are included) in vmware server2 beta1 but is seems that rtc is missing in this particular kernel? so why is it supported if rtc is required?
question: is the rt-kernel more than just adding rtc support to the kernel?
That's a good question. The rt kernel is designed for industrial, robotics and telco. (https://wiki.ubuntu.com/RealTime/Gutsy) It seems to do the trick for now. With the server kernel, I was seeing unnecessary cpu idling that caused the VMs to crawl.
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Very interesting observations you've done there, btone!
Wish you had collected some performance stat numbers/graphs while doing this. Those "lost interrupts" messages are often seen if the HZ inside the guests are the same or higher than the host's HZ. Using a kernel with a lower HZ (such as 100) is usually a good thing. Most 2.6 linux kernels are now shipped with url=http://bugs.centos.org/view.php?id=2189HZ=1000[/url], while Windows XP and most 2.4 kernels use HZ=100.
thanks for the tip. will try the HZ switch on a regular kernel. My HD crashed after only 1000 hours - my next install will be on ubuntu 8.04 - will see how this works out.
will try to collect some stats next time - any suggestions? vmstat ....