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To: Linus Walleij <linus.walleij@linaro.org>
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From: Bart Van Assche <bart.vanassche@sandisk.com>
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Date: Fri, 16 Sep 2016 13:53:39 +0200
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Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>,
	ksummit-discuss@lists.linux-foundation.org,
	Greg KH <gregkh@linuxfoundation.org>, Jens Axboe <axboe@fb.com>,
	hare@suse.de, Tejun Heo <tj@kernel.org>, osandov@osandov.com,
	Christoph Hellwig <hch@lst.de>
Subject: Re: [Ksummit-discuss] [TECH TOPIC] Addressing long-standing
 high-latency problems related to I/O
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On 09/16/2016 01:24 PM, Linus Walleij wrote:
> What do you guys at SanDisk use?

Hello Linus,

We use fio for block device performance measurements. Before we run fio 
we disable C-state and P-state transitions to make sure that the results 
will not depend on any frequency scaling algorithm. Furthermore, we 
install a udev rule that sets the following block layer parameters for 
non-rotational devices: add_random=0 and rq_affinity=2.

Bart.