Re: polling interval

From: void <void_at_f-m.fm>
Date: Tue, 15 Oct 2024 09:30:59 UTC 
On Tue, Oct 15, 2024 at 05:41:35PM +0900, Tomoaki AOKI wrote:

>IIRC, in ancient days, default kern_hz (HZ) was 100 and bumped to 1000
>(current default) at some point. So trying around 10000 or 5000 and
>if not satisfactory, try increasing or decreasing would be nice for
>recent amd64 hardwares. (It depends, though.)
>
>FYI, I'm configuring kern.hz=4096 in /boot/loader.conf. Lost where I've
>seen, but recommended by somewhere.

The test vm here defaulted to 100. I got best throughput by turning it down to
8. Not by a lot though. I've commented out the hz value for now and rebooted:

% sysctl -a | ug hz
14: kern.clockrate: { hz = 100, tick = 10000, profhz = 8128, stathz = 127 }
191: kern.hz_min: 8
192:  kern.hz_max: 137438
193: kern.hz: 100
6321:  vfs.deferred_unmount.retry_delay_hz: 100
7299:  debug.psm.hz: 20
8002:  hw.atkbd.hz: 0

this is on -current built a few hrs earlier today

I'll try with hz as 0 or -1. I wish I could remember the linux article, as they
have a setting *something* like this and it's called something different.

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