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Date: Wed, 24 Mar 2021 13:58:52 +0100
From: Mathieu Chouquet-Stringer <me+freebsd@mathieu.digital>
To: Martin Simmons <martin@lispworks.com>
Cc: freebsd-fs@freebsd.org
Subject: Re: Scrub incredibly slow with 13.0-RC3 (as well as RC1 & 2)
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On Wed, Mar 24, 2021 at 12:30:52PM +0000, Martin Simmons wrote:
> FWIW, I think the new scrub algorithm was added in 2018.

You're right, git says Wed Nov 15 20:27:01 2017 -0500

> You could try to profile it:
> 
> https://wiki.freebsd.org/DTrace/Tutorial#Lesson_9._Profile_On-CPU_Kernel_Stacks

dtrace, hello old friend... :-)

That's the next step...

-- 
Mathieu Chouquet-Stringer
            The sun itself sees not till heaven clears.
	             -- William Shakespeare --