kern.hz="100" stops high-pitched whine
Chuck Swiger
cswiger at mac.com
Mon Jul 2 16:51:32 UTC 2007
Jack Stone wrote:
[ ... ]
> A while ago, I noticed someone's kernel config that included:
> hertz=2000 which made me wonder where this setting info comes from?
>
> I've been using hertz=1000 however, with my much faster boxes, is this
> appropriate now?
It depends on what you are doing: it is most useful to tune HZ higher when
machines are being used as firewalls/routers and/or are using device polling.
Faster HZ rates cause greater system overhead but will give shorter latency,
up to a limiting point.
In simpler words, tuning HZ too high is bad. :-)
One needs to do measurements and tune appropriately.
--
-Chuck
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