Re: [Qemu-devel] Run Real Time Guest OS?

[Steve Ellenoff]

BRAD YOU ROCK!! LOL..

It works!!!

I'm not sure what you meant by "you would most certainly want a HZ value of 
1000 to try this", but I simply changed the #define to 4096 as you 
suggested, put it on my fastest machine, and it works perfectly! I didn't 
even get the message saying to echo > 1024 (or in this case 4096), it just 
worked!!

DUDE! I owe you a beer! THANK YOU!! :)

So why when I googled - did I see everywhere it talk about linux having a 
1ms max resolution for timers? I can dig up some links if you need me to. 
This is confusing and what led me down the road to thinking I needed RTLinux 
or some other thing. I"m so thrilled not to have to go there! Perhaps linux 
can't guarantee a reliable and consistent frequency for the timer at speeds 
above 1ms, and any one needing 100% reliable timing would need an RT OS? 
Sure seemed pretty rock solid for me when I ran it, though it's a peppy 
machine.

Anyway, your reply really made my day, no, heck it made my last 2 weeks, 
since my project is now nearing completion and is running perfectly so far 
thanks to this tiny change!

It's funny, I had thought to try it myself a few days ago, but was 
discouraged by what I read on google, and never bothered. DOH!

-Steve

> > Not at all.. for a single qemu instance on linux it tries to use the PIT 
> > in the rtc, and I've seen this run upto 8192hz. Why not crank it up in the 
> > qemu source t0 4096 and see what happens. It's not going to hurt anything 
> > in any case.
> > You would most certainly want a HZ value of 1000 to try this.
> >
> >
> > Brad