From: Keith Busch <kbusch@kernel.org>
To: Hannes Reinecke <hare@suse.de>
Cc: "Chaitanya Kulkarni" <chaitanyak@nvidia.com>,
"Javier González" <javier@javigon.com>,
"Damien Le Moal" <damien.lemoal@opensource.wdc.com>,
"Luis Chamberlain" <mcgrof@kernel.org>,
"Mikulas Patocka" <mpatocka@redhat.com>,
"linux-block@vger.kernel.org" <linux-block@vger.kernel.org>,
"Adam Manzanares" <a.manzanares@samsung.com>,
"linux-scsi@vger.kernel.org" <linux-scsi@vger.kernel.org>,
"dm-devel@redhat.com" <dm-devel@redhat.com>,
"linux-nvme@lists.infradead.org" <linux-nvme@lists.infradead.org>,
linux-fsdevel <linux-fsdevel@vger.kernel.org>,
"Jens Axboe" <axboe@kernel.dk>,
"msnitzer@redhat.com >> msnitzer@redhat.com"
<msnitzer@redhat.com>, "Bart Van Assche" <bvanassche@acm.org>,
"martin.petersen@oracle.com >> Martin K. Petersen"
<martin.petersen@oracle.com>,
"roland@purestorage.com" <roland@purestorage.com>,
"Christoph Hellwig" <hch@lst.de>,
"Frederick.Knight@netapp.com" <Frederick.Knight@netapp.com>,
"zach.brown@ni.com" <zach.brown@ni.com>,
"osandov@fb.com" <osandov@fb.com>,
"lsf-pc@lists.linux-foundation.org"
<lsf-pc@lists.linux-foundation.org>,
"djwong@kernel.org" <djwong@kernel.org>,
"josef@toxicpanda.com" <josef@toxicpanda.com>,
"clm@fb.com" <clm@fb.com>, "dsterba@suse.com" <dsterba@suse.com>,
"tytso@mit.edu" <tytso@mit.edu>, "jack@suse.com" <jack@suse.com>,
"Kanchan Joshi" <joshi.k@samsung.com>
Subject: Re: [RFC PATCH 3/3] nvme: add the "debug" host driver
Date: Fri, 4 Feb 2022 06:24:22 -0800 [thread overview]
Message-ID: <20220204142422.GA627690@dhcp-10-100-145-180.wdc.com> (raw)
In-Reply-To: <befa49b3-7606-a3ce-24f7-e184e3df41a3@suse.de>
On Fri, Feb 04, 2022 at 03:15:02PM +0100, Hannes Reinecke wrote:
> On 2/4/22 10:58, Chaitanya Kulkarni wrote:
>
> > and if that is the case why we don't have ZNS NVMeOF target
> > memory backed emulation ? Isn't that a bigger and more
> > complicated feature than Simple Copy where controller states
> > are involved with AENs ?
> >
> > ZNS kernel code testing is also done on QEMU, I've also fixed
> > bugs in the ZNS kernel code which are discovered on QEMU and I've not
> > seen any issues with that. Given that simple copy feature is way smaller
> > than ZNS it will less likely to suffer from slowness and etc (listed
> > above) in QEMU.
> >
> > my point is if we allow one, we will be opening floodgates and we need
> > to be careful not to bloat the code unless it is _absolutely
> > necessary_ which I don't think it is based on the simple copy
> > specification.
> >
>
> I do have a slightly different view on the nvme target code; it should
> provide the necessary means to test the nvme host code.
> And simple copy is on of these features, especially as it will operate as an
> exploiter of the new functionality.
The threshold to determine if the in-kernel fabrics target ought to
implement a feature should be if it's useful in a production.
Are users interested in copying data without using fabric bandwidth?
Yes.
Does anyone want a mocked up ZNS that has all the contraints and none of
the benefits? No.
WARNING: multiple messages have this Message-ID (diff)
From: Keith Busch <kbusch@kernel.org>
To: Hannes Reinecke <hare@suse.de>
Cc: "djwong@kernel.org" <djwong@kernel.org>,
"linux-nvme@lists.infradead.org" <linux-nvme@lists.infradead.org>,
"clm@fb.com" <clm@fb.com>,
"dm-devel@redhat.com" <dm-devel@redhat.com>,
"Adam Manzanares" <a.manzanares@samsung.com>,
"osandov@fb.com" <osandov@fb.com>,
"msnitzer@redhat.com >> msnitzer@redhat.com"
<msnitzer@redhat.com>, "Bart Van Assche" <bvanassche@acm.org>,
"linux-scsi@vger.kernel.org" <linux-scsi@vger.kernel.org>,
"Damien Le Moal" <damien.lemoal@opensource.wdc.com>,
"Christoph Hellwig" <hch@lst.de>,
"roland@purestorage.com" <roland@purestorage.com>,
"zach.brown@ni.com" <zach.brown@ni.com>,
"Chaitanya Kulkarni" <chaitanyak@nvidia.com>,
"Javier González" <javier@javigon.com>,
"josef@toxicpanda.com" <josef@toxicpanda.com>,
"linux-block@vger.kernel.org" <linux-block@vger.kernel.org>,
"Mikulas Patocka" <mpatocka@redhat.com>,
"dsterba@suse.com" <dsterba@suse.com>,
"Frederick.Knight@netapp.com" <Frederick.Knight@netapp.com>,
"Jens Axboe" <axboe@kernel.dk>, "tytso@mit.edu" <tytso@mit.edu>,
"Kanchan Joshi" <joshi.k@samsung.com>,
"martin.petersen@oracle.com >> Martin K. Petersen"
<martin.petersen@oracle.com>,
"Luis Chamberlain" <mcgrof@kernel.org>,
"jack@suse.com" <jack@suse.com>,
linux-fsdevel <linux-fsdevel@vger.kernel.org>,
"lsf-pc@lists.linux-foundation.org"
<lsf-pc@lists.linux-foundation.org>
Subject: Re: [dm-devel] [RFC PATCH 3/3] nvme: add the "debug" host driver
Date: Fri, 4 Feb 2022 06:24:22 -0800 [thread overview]
Message-ID: <20220204142422.GA627690@dhcp-10-100-145-180.wdc.com> (raw)
In-Reply-To: <befa49b3-7606-a3ce-24f7-e184e3df41a3@suse.de>
On Fri, Feb 04, 2022 at 03:15:02PM +0100, Hannes Reinecke wrote:
> On 2/4/22 10:58, Chaitanya Kulkarni wrote:
>
> > and if that is the case why we don't have ZNS NVMeOF target
> > memory backed emulation ? Isn't that a bigger and more
> > complicated feature than Simple Copy where controller states
> > are involved with AENs ?
> >
> > ZNS kernel code testing is also done on QEMU, I've also fixed
> > bugs in the ZNS kernel code which are discovered on QEMU and I've not
> > seen any issues with that. Given that simple copy feature is way smaller
> > than ZNS it will less likely to suffer from slowness and etc (listed
> > above) in QEMU.
> >
> > my point is if we allow one, we will be opening floodgates and we need
> > to be careful not to bloat the code unless it is _absolutely
> > necessary_ which I don't think it is based on the simple copy
> > specification.
> >
>
> I do have a slightly different view on the nvme target code; it should
> provide the necessary means to test the nvme host code.
> And simple copy is on of these features, especially as it will operate as an
> exploiter of the new functionality.
The threshold to determine if the in-kernel fabrics target ought to
implement a feature should be if it's useful in a production.
Are users interested in copying data without using fabric bandwidth?
Yes.
Does anyone want a mocked up ZNS that has all the contraints and none of
the benefits? No.
--
dm-devel mailing list
dm-devel@redhat.com
https://listman.redhat.com/mailman/listinfo/dm-devel
next prev parent reply other threads:[~2022-02-04 14:24 UTC|newest]
Thread overview: 183+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <CGME20220127071544uscas1p2f70f4d2509f3ebd574b7ed746d3fa551@uscas1p2.samsung.com>
2022-01-27 7:14 ` [LSF/MM/BFP ATTEND] [LSF/MM/BFP TOPIC] Storage: Copy Offload Chaitanya Kulkarni
2022-01-28 19:59 ` Adam Manzanares
2022-01-28 19:59 ` [dm-devel] " Adam Manzanares
2022-01-31 11:49 ` Johannes Thumshirn
2022-01-31 11:49 ` Johannes Thumshirn
2022-01-31 19:03 ` Bart Van Assche
2022-01-31 19:03 ` [dm-devel] " Bart Van Assche
2022-02-01 1:54 ` Luis Chamberlain
2022-02-01 1:54 ` Luis Chamberlain
2022-02-01 10:21 ` Javier González
2022-02-01 18:31 ` [RFC PATCH 0/3] NVMe copy offload patches Mikulas Patocka
2022-02-01 18:31 ` [dm-devel] " Mikulas Patocka
2022-02-01 18:32 ` [RFC PATCH 1/3] block: add copy offload support Mikulas Patocka
2022-02-01 18:32 ` [dm-devel] " Mikulas Patocka
2022-02-01 19:18 ` Bart Van Assche
2022-02-01 19:18 ` [dm-devel] " Bart Van Assche
2022-02-03 18:50 ` Mikulas Patocka
2022-02-03 18:50 ` Mikulas Patocka
2022-02-03 20:11 ` Keith Busch
2022-02-03 20:11 ` [dm-devel] " Keith Busch
2022-02-03 22:49 ` Bart Van Assche
2022-02-03 22:49 ` Bart Van Assche
2022-02-04 12:09 ` [dm-devel] " Mikulas Patocka
2022-02-04 12:09 ` Mikulas Patocka
2022-02-04 13:34 ` Jens Axboe
2022-02-04 13:34 ` [dm-devel] " Jens Axboe
2022-02-02 16:21 ` Keith Busch
2022-02-02 16:21 ` [dm-devel] " Keith Busch
2022-02-02 16:40 ` Mikulas Patocka
2022-02-02 16:40 ` [dm-devel] " Mikulas Patocka
2022-02-02 18:40 ` Knight, Frederick
2022-02-02 18:40 ` [dm-devel] " Knight, Frederick
2022-02-01 18:33 ` [RFC PATCH 2/3] nvme: " Mikulas Patocka
2022-02-01 18:33 ` [dm-devel] " Mikulas Patocka
2022-02-01 19:18 ` Bart Van Assche
2022-02-01 19:18 ` [dm-devel] " Bart Van Assche
2022-02-01 19:25 ` Mikulas Patocka
2022-02-01 19:25 ` [dm-devel] " Mikulas Patocka
2022-02-01 18:33 ` [RFC PATCH 3/3] nvme: add the "debug" host driver Mikulas Patocka
2022-02-01 18:33 ` [dm-devel] " Mikulas Patocka
2022-02-01 21:32 ` kernel test robot
2022-02-02 6:01 ` Adam Manzanares
2022-02-02 6:01 ` [dm-devel] " Adam Manzanares
2022-02-03 16:06 ` Luis Chamberlain
2022-02-03 16:06 ` Luis Chamberlain
2022-02-03 16:15 ` [dm-devel] " Christoph Hellwig
2022-02-03 16:15 ` Christoph Hellwig
2022-02-03 19:34 ` Luis Chamberlain
2022-02-03 19:34 ` [dm-devel] " Luis Chamberlain
2022-02-03 19:46 ` Adam Manzanares
2022-02-03 19:46 ` [dm-devel] " Adam Manzanares
2022-02-03 20:57 ` Mikulas Patocka
2022-02-03 20:57 ` Mikulas Patocka
2022-02-03 22:52 ` Adam Manzanares
2022-02-03 22:52 ` [dm-devel] " Adam Manzanares
2022-02-04 3:00 ` Chaitanya Kulkarni
2022-02-04 3:00 ` [dm-devel] " Chaitanya Kulkarni
2022-02-04 3:05 ` Chaitanya Kulkarni
2022-02-04 3:05 ` [dm-devel] " Chaitanya Kulkarni
2022-02-02 7:23 ` kernel test robot
2022-02-02 7:23 ` kernel test robot
2022-02-02 8:00 ` Chaitanya Kulkarni
2022-02-02 8:00 ` [dm-devel] " Chaitanya Kulkarni
2022-02-02 12:38 ` Klaus Jensen
2022-02-02 12:38 ` [dm-devel] " Klaus Jensen
2022-02-03 15:38 ` Luis Chamberlain
2022-02-03 15:38 ` Luis Chamberlain
2022-02-03 16:52 ` Keith Busch
2022-02-03 16:52 ` [dm-devel] " Keith Busch
2022-02-03 19:50 ` Adam Manzanares
2022-02-03 19:50 ` [dm-devel] " Adam Manzanares
2022-02-04 3:12 ` Chaitanya Kulkarni
2022-02-04 3:12 ` [dm-devel] " Chaitanya Kulkarni
2022-02-04 6:28 ` Damien Le Moal
2022-02-04 6:28 ` [dm-devel] " Damien Le Moal
2022-02-04 7:58 ` Chaitanya Kulkarni
2022-02-04 7:58 ` [dm-devel] " Chaitanya Kulkarni
2022-02-04 8:24 ` Javier González
2022-02-04 8:24 ` [dm-devel] " Javier González
2022-02-04 9:58 ` Chaitanya Kulkarni
2022-02-04 9:58 ` [dm-devel] " Chaitanya Kulkarni
2022-02-04 11:34 ` Javier González
2022-02-04 11:34 ` [dm-devel] " Javier González
2022-02-04 14:15 ` Hannes Reinecke
2022-02-04 14:15 ` [dm-devel] " Hannes Reinecke
2022-02-04 14:24 ` Keith Busch [this message]
2022-02-04 14:24 ` Keith Busch
2022-02-04 16:01 ` Christoph Hellwig
2022-02-04 16:01 ` [dm-devel] " Christoph Hellwig
2022-02-04 19:41 ` [RFC PATCH 0/3] NVMe copy offload patches Nitesh Shetty
2022-02-04 19:41 ` [dm-devel] " Nitesh Shetty
[not found] ` <CGME20220207141901epcas5p162ec2387815be7a1fd67ce0ab7082119@epcas5p1.samsung.com>
2022-02-07 14:13 ` [PATCH v2 00/10] Add Copy offload support Nitesh Shetty
2022-02-07 14:13 ` [dm-devel] " Nitesh Shetty
[not found] ` <CGME20220207141908epcas5p4f270c89fc32434ea8b525fa973098231@epcas5p4.samsung.com>
2022-02-07 14:13 ` [PATCH v2 01/10] block: make bio_map_kern() non static Nitesh Shetty
2022-02-07 14:13 ` [dm-devel] " Nitesh Shetty
[not found] ` <CGME20220207141913epcas5p4d41cb549b7cca1ede5c7a66bbd110da0@epcas5p4.samsung.com>
2022-02-07 14:13 ` [PATCH v2 02/10] block: Introduce queue limits for copy-offload support Nitesh Shetty
2022-02-07 14:13 ` [dm-devel] " Nitesh Shetty
2022-02-08 7:01 ` Damien Le Moal
2022-02-08 7:01 ` [dm-devel] " Damien Le Moal
2022-02-08 18:43 ` Nitesh Shetty
2022-02-08 18:43 ` [dm-devel] " Nitesh Shetty
[not found] ` <CGME20220207141918epcas5p4f9badc0c3f3f0913f091c850d2d3bd81@epcas5p4.samsung.com>
2022-02-07 14:13 ` [PATCH v2 03/10] block: Add copy offload support infrastructure Nitesh Shetty
2022-02-07 14:13 ` [dm-devel] " Nitesh Shetty
2022-02-07 22:45 ` kernel test robot
2022-02-07 22:45 ` kernel test robot
2022-02-07 22:45 ` [dm-devel] " kernel test robot
2022-02-07 23:26 ` kernel test robot
2022-02-07 23:26 ` kernel test robot
2022-02-07 23:26 ` [dm-devel] " kernel test robot
2022-02-08 7:21 ` Damien Le Moal
2022-02-08 7:21 ` [dm-devel] " Damien Le Moal
2022-02-09 10:22 ` Nitesh Shetty
2022-02-09 10:22 ` [dm-devel] " Nitesh Shetty
[not found] ` <CGME20220207141924epcas5p26ad9cf5de732224f408aded12ed0a577@epcas5p2.samsung.com>
2022-02-07 14:13 ` [PATCH v2 04/10] block: Introduce a new ioctl for copy Nitesh Shetty
2022-02-07 14:13 ` [dm-devel] " Nitesh Shetty
2022-02-09 3:39 ` kernel test robot
2022-02-09 3:39 ` kernel test robot
2022-02-09 3:39 ` kernel test robot
[not found] ` <CGME20220207141930epcas5p2bcbff65f78ad1dede64648d73ddb3770@epcas5p2.samsung.com>
2022-02-07 14:13 ` [PATCH v2 05/10] block: add emulation " Nitesh Shetty
2022-02-07 14:13 ` [dm-devel] " Nitesh Shetty
2022-02-08 3:20 ` kernel test robot
2022-02-08 3:20 ` kernel test robot
2022-02-08 3:20 ` [dm-devel] " kernel test robot
2022-02-16 13:32 ` Mikulas Patocka
2022-02-16 13:32 ` Mikulas Patocka
2022-02-17 13:18 ` Nitesh Shetty
2022-02-17 13:18 ` [dm-devel] " Nitesh Shetty
[not found] ` <CGME20220207141937epcas5p2bd57ae35056c69b3e2f9ee2348d6af19@epcas5p2.samsung.com>
2022-02-07 14:13 ` [PATCH v2 06/10] nvme: add copy support Nitesh Shetty
2022-02-07 14:13 ` [dm-devel] " Nitesh Shetty
2022-02-10 7:08 ` kernel test robot
2022-02-10 7:08 ` kernel test robot
2022-02-10 7:08 ` kernel test robot
[not found] ` <CGME20220207141942epcas5p4bda894a5833513c9211dcecc7928a951@epcas5p4.samsung.com>
2022-02-07 14:13 ` [PATCH v2 07/10] nvmet: add copy command support for bdev and file ns Nitesh Shetty
2022-02-07 14:13 ` [dm-devel] " Nitesh Shetty
2022-02-07 18:10 ` kernel test robot
2022-02-07 18:10 ` kernel test robot
2022-02-07 18:10 ` [dm-devel] " kernel test robot
2022-02-07 20:12 ` kernel test robot
2022-02-07 20:12 ` kernel test robot
2022-02-07 20:12 ` [dm-devel] " kernel test robot
2022-02-10 8:31 ` kernel test robot
2022-02-10 8:31 ` kernel test robot
2022-02-10 8:31 ` kernel test robot
[not found] ` <CGME20220207141948epcas5p4534f6bdc5a1e2e676d7d09c04f8b4a5b@epcas5p4.samsung.com>
2022-02-07 14:13 ` [PATCH v2 08/10] dm: Add support for copy offload Nitesh Shetty
2022-02-07 14:13 ` [dm-devel] " Nitesh Shetty
2022-02-16 13:51 ` Mikulas Patocka
2022-02-16 13:51 ` Mikulas Patocka
2022-02-24 12:42 ` Nitesh Shetty
2022-02-24 12:42 ` [dm-devel] " Nitesh Shetty
2022-02-25 9:12 ` Mikulas Patocka
2022-02-25 9:12 ` [dm-devel] " Mikulas Patocka
[not found] ` <CGME20220207141953epcas5p32ccc3c0bbe642cea074edefcc32302a5@epcas5p3.samsung.com>
2022-02-07 14:13 ` [PATCH v2 09/10] dm: Enable copy offload for dm-linear target Nitesh Shetty
2022-02-07 14:13 ` [dm-devel] " Nitesh Shetty
[not found] ` <CGME20220207141958epcas5p25f1cd06726217696d13c2dfbea010565@epcas5p2.samsung.com>
2022-02-07 14:13 ` [PATCH v2 10/10] dm kcopyd: use copy offload support Nitesh Shetty
2022-02-07 14:13 ` [dm-devel] " Nitesh Shetty
2022-02-07 9:57 ` [LSF/MM/BFP ATTEND] [LSF/MM/BFP TOPIC] Storage: Copy Offload Nitesh Shetty
2022-02-07 9:57 ` [dm-devel] " Nitesh Shetty
2022-02-02 5:57 ` Kanchan Joshi
2022-02-02 5:57 ` [dm-devel] " Kanchan Joshi
2022-02-07 10:45 ` David Disseldorp
2022-02-07 10:45 ` [dm-devel] " David Disseldorp
2022-03-01 17:34 ` Nikos Tsironis
2022-03-01 17:34 ` [dm-devel] " Nikos Tsironis
2022-03-01 21:32 ` Chaitanya Kulkarni
2022-03-03 18:36 ` [dm-devel] " Nikos Tsironis
2022-03-03 18:36 ` Nikos Tsironis
2022-03-08 20:48 ` Nikos Tsironis
2022-03-08 20:48 ` [dm-devel] " Nikos Tsironis
2022-03-09 8:51 ` Mikulas Patocka
2022-03-09 8:51 ` Mikulas Patocka
2022-03-09 15:49 ` Nikos Tsironis
2022-03-09 15:49 ` [dm-devel] " Nikos Tsironis
[not found] <CGME20220209075901epcas5p3cff468deadd8ef836522f032bd4ed36c@epcas5p3.samsung.com>
2022-02-08 23:31 ` [PATCH v2 03/10] block: Add copy offload support infrastructure kernel test robot
2022-02-09 7:48 ` Dan Carpenter
2022-02-09 7:48 ` [dm-devel] " Dan Carpenter
2022-02-09 7:48 ` Dan Carpenter
2022-02-09 10:32 ` Nitesh Shetty
2022-02-10 6:13 ` Nitesh Shetty
2022-02-09 10:32 ` [dm-devel] " Nitesh Shetty
2022-02-10 22:49 [PATCH v2 07/10] nvmet: add copy command support for bdev and file ns kernel test robot
2022-02-11 7:52 ` Dan Carpenter
2022-02-11 7:52 ` [dm-devel] " Dan Carpenter
2022-02-11 7:52 ` Dan Carpenter
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