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From: Paolo Valente <paolo.valente@linaro.org>
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Date: Wed, 21 Sep 2016 16:37:53 +0200
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To: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>,
	ksummit-discuss@lists.linux-foundation.org,
	Jens Axboe <axboe@fb.com>, hare@suse.de,
	Tejun Heo <tj@kernel.org>, osandov@osandov.com, hch@lst.de
Subject: Re: [Ksummit-discuss] [TECH TOPIC] Addressing long-standing
	high-latency problems related to I/O
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> Il giorno 21 set 2016, alle ore 16:30, Bart Van Assche =
<bart.vanassche@sandisk.com> ha scritto:
>=20
> On 09/16/16 00:55, Paolo Valente wrote:
>> Linux systems suffers from long-standing high-latency problems, at
>> system and application level, related to I/O.
>=20
> Hello Paolo,
>=20

Hi

> Are you aware of Jens' throttled background buffered writeback work? =
If not, can you repeat your measurements against a kernel on which these =
patches have been applied?

Already done (see below).

> See also http://www.spinics.net/lists/linux-fsdevel/msg101391.html.
>=20

A brief report of the outcome of my measurements is in this email of =
mine on the same thread:
http://www.spinics.net/lists/linux-fsdevel/msg101430.html

In short, application start-up time happened to be about the same with =
and without writeback throttling (actually slightly higher with =
throttling, for, e.g., gnome-terminal).

Thanks,
Paolo

> Thanks,
>=20
> Bart.
>=20