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Subject: Re: extremely slow disk I/O after updating to 12.0
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From: David Demelier <markand@malikania.fr>
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Le 03/07/2019 à 13:43, Robert Schulze a écrit :
> we have seen a drop in I/O performance beginning with 11.2-RELEASE.
> Try disabling scattered ABD:
> 
> sysctl vfs.zfs.abd_scatter_enabled=0

Thanks for the answer. I'm trying this.

Is this tunable available at boot (i.e. /boot/loader.conf) or do you put 
it in /etc/sysctl.conf?

Regards,

-- 
David