From owner-freebsd-fs@FreeBSD.ORG  Thu Dec  9 18:13:41 2010
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To: Kostik Belousov <kostikbel@gmail.com>
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Date: Thu, 09 Dec 2010 10:13:39 -0800
From: Kirk McKusick <mckusick@mckusick.com>
Cc: freebsd-fs@freebsd.org, pjd@freebsd.org,
	Oliver Fromme <olli@lurza.secnetix.de>
Subject: Re: TRIM support for UFS? 
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Other than the nit pointed out by Pawel, the diffs look good to me.
You should consider adding the -t option to newfs so that the TRIM
option can be specified at the time the filesystem is created (as
a general rule, anything you can do with tunefs should also be
possible with newfs).

I agree with your decision to let administrators opt-out of doing
TRIM. If experience shows it to be generally useful to have it on,
we can change the default to enabled later. If we do change the
default to enabled, then we will want to delete the warning about TRIM
not being supported by the underlying disk that you added at mount
time as we would start getting a lot of them for all the non-SSD disks.

	Kirk McKusick