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([2601:647:4802:9070:3910:5e55:b19d:2395]) by smtp.gmail.com with ESMTPSA id s14sm2265626pgv.74.2020.02.19.23.48.10 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 19 Feb 2020 23:48:10 -0800 (PST) Subject: Re: [PATCH 0/4] nvmet: add set feature based timestamp support To: Chaitanya Kulkarni , Christoph Hellwig , Keith Busch References: <20200218214338.25088-1-chaitanya.kulkarni@wdc.com> <20200218231007.GA18306@redsun51.ssa.fujisawa.hgst.com> <20200219145907.GA17748@lst.de> From: Sagi Grimberg Message-ID: <51465fc5-6f49-5790-4d85-df5f841e2f8e@grimberg.me> Date: Wed, 19 Feb 2020 23:48:09 -0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.9.0 MIME-Version: 1.0 In-Reply-To: Content-Language: en-US X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200219_234816_989445_AF07F084 X-CRM114-Status: GOOD ( 15.80 ) X-BeenThere: linux-nvme@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: "linux-nvme@lists.infradead.org" Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: "linux-nvme" Errors-To: linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org >>> The last three ought to be a single patch IMO since those should really >>> from an inseparable package deal for this feature. >> >> Agreed. >> > Agree, just made series into small chunks so that it will be easier > for a reviewer to go through changes in a botttom up manner. >>> As to why we'd support this feature, the spec says "The use of the >>> Timestamp is outside the scope of this specification". Is there anything >>> interesting we can do with this? >> >> I can't really think of why this is useful either.. >> > If a host is dealing with different controllers which are on a different > machines it will be easier to sync timestamp and read it's value. > > Although spec doesn't specify the right use, having this feature will > allow application(s) (if any) to use it if needed. Do we know why is that needed? _______________________________________________ linux-nvme mailing list linux-nvme@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-nvme