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Subject: Re: How to speed up slow zpool scrub?
To: Ronald Klop <ronald-lists@klop.ws>, freebsd-fs@FreeBSD.org
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From: Andriy Gapon <avg@FreeBSD.org>
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Date: Fri, 29 Apr 2016 17:37:32 +0300
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On 29/04/2016 17:28, Ronald Klop wrote:
> Just like UFS makes an assumption about correct memory and correct disks?
> 
> ECC helps ZFS as much as ECC helps UFS.
> And without ECC ZFS provides more failsafes than UFS. But nothing is perfect.
> You guys make it sound like ZFS has no added benefits if you don't use ECC,
> which is not true.
> 
> UFS < ZFS < ZFS+ECC
> And UFS+ECC is somewhere in between probably.
> As long as people understand the risks/benefits things are ok.

One thing to keep in mind is that ZFS on-disk structures are much more complex
than those of UFS.  It is much harder to recover from some ZFS failure modes.
(And there is no zfsck...)

-- 
Andriy Gapon