From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Tue, 6 Oct 2020 10:02:24 +0530 From: Krishna Kanth Reddy Subject: Re: [PATCH 0/3] v1 Patchset : Zone Explicit Open support Message-ID: <20201006043224.GA19210@test-zns> MIME-Version: 1.0 In-Reply-To: Content-Type: multipart/mixed; boundary="----.SbLpEChV8y8LoQpb_2t7nYdot55MkfN9twA47R_fm6-MYmY=_45d43_" References: <20200929125950.20343-1-krish.reddy@samsung.com> To: Damien Le Moal Cc: "axboe@kernel.dk" , "fio@vger.kernel.org" List-ID: ------.SbLpEChV8y8LoQpb_2t7nYdot55MkfN9twA47R_fm6-MYmY=_45d43_ Content-Type: text/plain; charset="utf-8"; format="flowed" Content-Disposition: inline On Tue, Sep 29, 2020 at 04:32:09PM +0000, Damien Le Moal wrote: >On 2020/09/29 22:03, Krishna Kanth Reddy wrote: >> 1. Added a new FIO option zone_open. >> When it is enabled, Zones will be opened explicitly before sending I/Os. >> 2. Add support for open_zones in libzbc I/O engine >> 3. t/zbd: Add support to verify Zone Explicit Open >> >> This is a RFC. >> Feedback / Comments will help in improving this further. > >My main question is why ? There is no performance benefit on the drive side from >doing explicit zone open. On the contrary, performance may go down due to the >added command overhead. So why do this ? What is your goal ? > >Using the max_open_zones=N option, fio writes will be limited to a set of N >zones, implicitly open, until the zones are full (not open anymore) and new >zones chosen (becoming implicitly open with writes). Adding explicit zone open >will not give you anything more with this option used. And if you do not use it, >performance with random writes will significantly go down. > >So please try to give convincing reasons for this. > It is a building block for future TPs. We would like to do the pre-work and add the right option abstraction. Zone open is 'implicit' by default. Hence there won't be a performance drop with the newly added code. >> >> Ankit Kumar (2): >> Add support for Explicit open zones >> Add support for open_zones in libzbc I/O engine. >> >> Krishna Kanth Reddy (1): >> t/zbd: Add support to verify Zone Explicit Open >> >> HOWTO | 13 ++++++++ >> engines/libzbc.c | 42 +++++++++++++++++++++++++ >> engines/skeleton_external.c | 12 ++++++++ >> fio.1 | 11 +++++++ >> ioengines.h | 2 ++ >> options.c | 20 ++++++++++++ >> oslib/blkzoned.h | 7 +++++ >> oslib/linux-blkzoned.c | 26 ++++++++++++++++ >> t/zbd/test-zbd-support | 27 ++++++++++++++++ >> thread_options.h | 7 +++++ >> zbd.c | 61 +++++++++++++++++++++++++++++++++++++ >> 11 files changed, 228 insertions(+) >> > > >-- >Damien Le Moal >Western Digital Research > ------.SbLpEChV8y8LoQpb_2t7nYdot55MkfN9twA47R_fm6-MYmY=_45d43_ Content-Type: text/plain; charset="utf-8" ------.SbLpEChV8y8LoQpb_2t7nYdot55MkfN9twA47R_fm6-MYmY=_45d43_--