From owner-freebsd-fs@freebsd.org  Wed Mar  2 09:43:49 2016
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Date: Wed, 02 Mar 2016 10:43:37 +0100
From: Miroslav Lachman <000.fbsd@quip.cz>
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To: Bob Friesenhahn <bfriesen@simple.dallas.tx.us>
CC: Steven Hartland <killing@multiplay.co.uk>, freebsd-fs@freebsd.org
Subject: Re: abnormally high CPU load after zfs destroy
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Bob Friesenhahn wrote on 03/02/2016 03:50:
> On Tue, 1 Mar 2016, Miroslav Lachman wrote:
>
>> Steven Hartland wrote on 02/29/2016 22:21:
>>> Its likely churning through the actual delete, show system processes in
>>> top and you'll see it.
>>
>> Yes, there are about 300 kernel thread doing ZFS work, but should it
>> really bomb the system that way? The system is heavilly lagging for
>> about 10 minutes. Are there any sysctl to control this behavior?
>
> Is it possible that you enabled the dedup feature?

No, dedup is disabled and I never tried it on this machine.

Miroslav Lachman