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Date:   Wed, 16 Dec 2020 00:45:59 +0100
From:   Pavel Machek <pavel@ucw.cz>
To:     Johannes Thumshirn <Johannes.Thumshirn@wdc.com>
Cc:     Javier =?iso-8859-1?Q?Gonz=E1lez?= <javier@javigon.com>,
        Hannes Reinecke <hare@suse.de>, Christoph Hellwig <hch@lst.de>,
        SelvaKumar S <selvakuma.s1@samsung.com>,
        "linux-nvme@lists.infradead.org" <linux-nvme@lists.infradead.org>,
        "kbusch@kernel.org" <kbusch@kernel.org>,
        "axboe@kernel.dk" <axboe@kernel.dk>,
        Damien Le Moal <Damien.LeMoal@wdc.com>,
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Subject: Re: [RFC PATCH v2 0/2] add simple copy support
Message-ID: <20201215234558.GA18281@amd>
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Hi!

> > Good idea. Are you thinking of a sysfs entry to select the backend?
>=20
> Not sure on this one, initially I thought of a sysfs file, but then
> how would you do it. One "global" sysfs entry is probably a bad idea.
> Having one per block device to select native vs emulation maybe? And
> a good way to benchmark.
>=20
> The other idea would be a benchmark loop on boot like the raid library
> does.

Doing copy benchmarking would require writes on the media, right?

Kernel should not do such stuff without userspace requesting it...

Best regards,
								Pavel
--=20
http://www.livejournal.com/~pavelmachek

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