Quation about HZ kernel option

Artem Kuchin matrix at itlegion.ru
Thu Oct 4 08:42:43 PDT 2007

Craig Boston wrote:
> On Thu, Oct 04, 2007 at 02:32:39PM +0200, Oliver Fromme wrote:
>> In that case, I would recommend not to override the
>> default at all (which is 1000).
> ISTM that it would be better to use kern.hz=100 in this case.
> My reasoning is that a web server shouldn't be terribly sensitive to
> latency, so it's better to have longer quantums to get more work done
> without context switching overhead.  If you're not using polling,
> you'll be getting interrupts for network traffic anyway.

That what i personally thought. However 100 seems to be too rough.
I just feel so, no reasoning behind this ;)
Maybe 200-300 is better than 100 and better than 1000?
I wonder how to build a test case for this to find best settings for
web server, so others will not stuggle with this on the future.

> With polling on however, a high HZ value makes sense.

polling does not make sense in case of webhosting though ;)


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