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Date: Fri, 7 Aug 2015 09:30:59 +0200
From: Christoph Hellwig <hch@lst.de>
To: Kent Overstreet <kent.overstreet@gmail.com>
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Cc: Mike Snitzer <snitzer@redhat.com>, Neil Brown <neilb@suse.de>,
	Ming Lei <ming.lei@canonical.com>, dm-devel@redhat.com,
	Joshua Morris <josh.h.morris@us.ibm.com>, Alasdair Kergon <agk@redhat.com>,
	Lars Ellenberg <drbd-dev@lists.linbit.com>,
	Philip Kelleher <pjk1939@linux.vnet.ibm.com>,
	Christoph Hellwig <hch@lst.de>, Christoph Hellwig <hch@infradead.org>,
	Nitin Gupta <ngupta@vflare.org>, Ming Lin <ming.l@ssi.samsung.com>,
	Oleg Drokin <oleg.drokin@intel.com>,
	Al Viro <viro@zeniv.linux.org.uk>, Ming Lin <mlin@kernel.org>,
	Jens Axboe <axboe@kernel.dk>, Andreas Dilger <andreas.dilger@intel.com>,
	Geoff Levand <geoff@infradead.org>, Jiri Kosina <jkosina@suse.cz>,
	lkml <linux-kernel@vger.kernel.org>, Jim Paris <jim@jtan.com>,
	Minchan Kim <minchan@kernel.org>, Dongsu Park <dpark@posteo.net>,
	drbd-user@lists.linbit.com
Subject: Re: [Drbd-dev] [PATCH v5 01/11] block: make generic_make_request
	handle	arbitrarily sized bios
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On Thu, Aug 06, 2015 at 05:00:04PM -0700, Kent Overstreet wrote:
> Why is it that we don't want to send giant discards? Is it a latency issue?

Yes.  Take a look at the "Configurable max discard size" thread(s).