so much clock interrupts?!

Chuck Swiger cswiger at
Sun Nov 27 03:27:44 GMT 2005

cpghost wrote:
> On Fri, Nov 25, 2005 at 07:45:03AM +0100, Markus Trippelsdorf wrote:
>> Yes, I guess it increases performance on a high throughput webserver or 
>> router that uses polling. But on the Desktop it only increases the
>> overhead without any benefits at all. 2000 interrupts per second per core
>> for the timer is a ridiculous high number and I reduce it simply for
>> aesthetic reasons.

The default settings try to give a 1-millisecond timing granularity, which 
seems to work pretty well on Pentium-grade and above hardware.  Desktop tasks 
now include soft realtime work like displaying video clips, and obviously 
realtime 3D games benefit from it HZ=1000.

> I'm also wondering wether 1000 Hz on a Soekris net4801 (Geode 266 MHz)
> won't be overkill. I'm planning to migrate some of them from 5.4 to 6.0,
> and doubting wether to change the new default to its more conservative
> previous setting of 100 Hz.

For what it's worth, I have kern.hz="200" in /boot/loader.conf on an EPIA-M6000 
running 6.0-STABLE...


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