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Date: Thu, 11 Sep 2014 09:24:41 +0300
From: Andriy Gapon <avg@FreeBSD.org>
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To: Steven Hartland <killing@multiplay.co.uk>,
 Aristedes Maniatis <ari@ish.com.au>,
 freebsd-stable <freebsd-stable@FreeBSD.org>
Subject: Re: getting to 4K disk blocks in ZFS
References: <540FF3C4.6010305@ish.com.au> <54100258.2000505@freebsd.org>
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On 11/09/2014 04:22, Steven Hartland wrote:
> 
> ----- Original Message ----- From: "Aristedes Maniatis" <ari@ish.com.au>
>> Should the FreeBSD project change this minimum in the next release?
>> There seems to be no downside and a huge amount of pain for people
>> who stumble along with the defaults not knowing what a mess they are
>> creating to solve later.
> 
> The downside is wasted space which can be significant and hence when
> I last suggested just this it was unfortunately rejected.
> 
> We still maintain a local patch to our source tree which does just
> this because, as you've mentioned, we don't want the pain so its
> easier to just run everything as 4k.


Another downside is 1/4th of uberblocks, 32 vs 128.
Also, automatic sector size detection works great for me and I've never had a
need to manually tweak ashift.

-- 
Andriy Gapon