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Date: Sat, 27 Mar 2021 17:36:05 +0100
From: Mathieu Chouquet-Stringer <me+freebsd@mathieu.digital>
To: freebsd-fs@freebsd.org
Subject: Re: Scrub incredibly slow with 13.0-RC3 (as well as RC1 & 2)
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On Sat, Mar 27, 2021 at 05:06:43PM +0100, Mathieu Chouquet-Stringer wrote:
> I am attaching a flamegraph for that busy process: again a lot of
> hpet_get_timecount... So I went and disabled hpet in kvm: I gained 30
> seconds and again, playing with vfs.read_max made no difference but then
> again it's a ssd. And given I still am cpu bound I'm not sure I'll gain
> anything by playing with block sizes... But the first lesson is to not
> use hpet with KVM.

Forgot to attache the svg file...
-- 
Mathieu Chouquet-Stringer
            The sun itself sees not till heaven clears.
	             -- William Shakespeare --