HZ=100 ?? vmware

jason jason at ec.rr.com
Thu Oct 14 13:23:43 PDT 2004

dick hoogendijk wrote:

>Okey, I found out I need to increase the HZ=100 default in the kernel
>config to a higher number. I also understand it decreases  system
>response times.
>So, what I need to know is the lowest setup for HZ=??? to be able to run
>vmware3 in full screen. I got to get rid of the "rtc: 100 > kern.hz"
>Google tells me to increase to HZ=1200 but is this not too high?
In man polling a kernel config of HZ=1000 is the default if you want to 
use polling.  I am not sure, but if vmware is using the same HZ setting  
as polling does then 1200 is not too high.  If I understand it right, 
the HZ setting tells stuff how often to checkin to see if work needs 
doing.  100hz would be way too low.  Every 100hz on say a 2ghz machince 
would requirer you to spend a lot of time on something every 
sec(2billion/100 per sec if I am right).  Maybe nothing because you are 
delaying some programs that you want to execute, not pause and wait 
every 100hz.  This would most likely slow everything down, a higher 
number would make things smoother and faster, but only to a point.  Its 
kind of complicated, but when you find the right spot(somewhere in the 
middle) everything is good.  If you had a 4ghz machince you may want an 
even larger number.  If I am wrong I am sure there will be a followup 


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