From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jeff Moyer <jmoyer-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
Subject: Re: [PATCH 2/2] block: create ioctl to discard-or-zeroout a range of blocks
Date: Fri, 18 Mar 2016 11:15:23 -0400
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In-Reply-To: <20160318032023.GK23593-AKGzg7BKzIDYtjvyW6yDsg@public.gmane.org> (Theodore Ts'o's message of
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To: Theodore Ts'o <tytso-3s7WtUTddSA@public.gmane.org>
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"Theodore Ts'o" <tytso-3s7WtUTddSA@public.gmane.org> writes:

> I do think that using TRIM in various causes where we are doing an
> fallocate does make sense for non-rotational devices.  In general TRIM
> should be fast enough that that I'd be surprised that people would be
> complaining --- especially since most of the time, fallocate isn't on
> the timing-critical path of most applications.

TRIM/UNMAP isn't just supported on solid state devices, though.  I do
recall some enterprise thinly provisioned storage that would take ages
to discard large regions.  I think that caused us to change the defaults
for mkfs, right?

Cheers,
Jeff