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Date: Tue, 1 Mar 2016 20:50:37 -0600 (CST)
From: Bob Friesenhahn <bfriesen@simple.dallas.tx.us>
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To: Miroslav Lachman <000.fbsd@quip.cz>
cc: Steven Hartland <killing@multiplay.co.uk>, freebsd-fs@freebsd.org
Subject: Re: abnormally high CPU load after zfs destroy
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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?

Bob
-- 
Bob Friesenhahn
bfriesen@simple.dallas.tx.us, http://www.simplesystems.org/users/bfriesen/
GraphicsMagick Maintainer,    http://www.GraphicsMagick.org/