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Tue, 9 Aug 2022 03:47:03 +0000 From: Rory Chen To: Arie van der Hoeven , Muhammad Ahmad , "linux-block@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "jack@suse.cz" , "andrea.righi@canonical.com" , "glen.valante@linaro.org" , "axboe@kernel.dk" , Tyler Erickson , Michael English , Andrew Ring , Varun Boddu , Paolo Valente Subject: Re: [PATCH 0/8] block, bfq: extend bfq to support multi-actuator drives Thread-Topic: [PATCH 0/8] block, bfq: extend bfq to support multi-actuator drives Thread-Index: AQHYhxl16wZu53I2nkyhDu//lRykYq2Hfy1sgB6yWuQ= Date: Tue, 9 Aug 2022 03:47:03 +0000 Message-ID: References: <20220623155335.6147-1-paolo.valente@linaro.org> In-Reply-To: Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: msip_labels: MSIP_Label_56e366eb-86f1-4645-85a7-f29555b26fee_Enabled=True;MSIP_Label_56e366eb-86f1-4645-85a7-f29555b26fee_SiteId=d466216a-c643-434a-9c2e-057448c17cbe;MSIP_Label_56e366eb-86f1-4645-85a7-f29555b26fee_SetDate=2022-08-09T03:47:02.803Z;MSIP_Label_56e366eb-86f1-4645-85a7-f29555b26fee_Name=Seagate Internal;MSIP_Label_56e366eb-86f1-4645-85a7-f29555b26fee_ContentBits=0;MSIP_Label_56e366eb-86f1-4645-85a7-f29555b26fee_Method=Standard; 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charset="Windows-1252" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-OriginatorOrg: seagate.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-AuthSource: SJ0PR20MB4409.namprd20.prod.outlook.com X-MS-Exchange-CrossTenant-Network-Message-Id: d44d8958-db5d-43f0-68f1-08da79b9d276 X-MS-Exchange-CrossTenant-originalarrivaltime: 09 Aug 2022 03:47:03.2764 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: d466216a-c643-434a-9c2e-057448c17cbe X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-CrossTenant-userprincipalname: MN1rvm7pXb7l509O/pQaKlbG4q6kc9MEk/x8X5JUBrRSkU9Rs0vEjOlyiai0qby7620MEqa8mmQ5uQ/aSLxkFg== X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH0PR20MB4494 X-Spam-Status: No, score=-5.0 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_MED, SPF_HELO_PASS,SPF_NONE,T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Resend the mail as plain text because previous mail with rich text makes so= me mess and forget to add others at Seagate who worked on validating the patch as well(Muhammad, Michael, Andrew, Varun,Tyler) Hi Paolo, I am from Seagate China and face a problem when I=92m evaluating the bfq pa= tches. Could you please check? Thanks Issue statement When running performance test on bfq patch, I observed warning message "bfq= _actuator_index: bio sector out of ranges: end=3D35156656128" and OS hung s= uddenly after some hours. The warning message is reported from function bfq_actuator_index which dete= rmines IO request is in which index of actuators. The bio_end_sector is 35= 156656128 but the max LBA for the drive is 35156656127 so it=92s beyond the= LBA range. I captured the block trace and didn=92t found request LBA 3515= 6656128 instead only found max request LBA 35156656127. I=92m not sure if this warning message is related to later OS hung. Problem environment Kernel base is 5.18.9 Test HDD drive is Seagate ST18000NM0092 dual actuator SATA. Actuator LBA mapping by reading VPD B9 Concurrent positioning ranges VPD page: LBA range number:0 number of storage elements:1 starting LBA:0x0 number of LBAs:0x417c00000 [17578328064] LBA range number:1 number of storage elements:1 starting LBA:0x417c00000 number of LBAs:0x417c00000 [17578328064] From: Paolo Valente Sent: Thursday, June 23, 2022 8:53 AM To: Jens Axboe Cc: linux-block@vger.kernel.org ; linux-kernel= @vger.kernel.org ; jack@suse.cz ; andrea.righi@canonical.com ; glen.valante@li= naro.org ; Arie van der Hoeven ; Paolo Valente Subject: [PATCH 0/8] block, bfq: extend bfq to support multi-actuator drive= s This message has originated from an External Source. Please use proper judg= ment and caution when opening attachments, clicking links, or responding to= this email. Hi, this patch series extends BFQ so as to optimize I/O dispatch to multi-actuator drives. In particular, this extension addresses the following issue. Multi-actuator drives appear as a single device to the I/O subsystem [1]. Yet they address commands to different actuators internally, as a function of Logical Block Addressing (LBAs). A given sector is reachable by only one of the actuators. For example, Seagate=92s Serial Advanced Technology Attachment (SATA) version contains two actuators and maps the lower half of the SATA LBA space to the lower actuator and the upper half to the upper actuator. Evidently, to fully utilize actuators, no actuator must be left idle or underutilized while there is pending I/O for it. To reach this goal, the block layer must somehow control the load of each actuator individually. This series enriches BFQ with such a per-actuator control, as a first step. Then it also adds a simple mechanism for guaranteeing that actuators with pending I/O are never left idle. See [1] for a more detailed overview of the problem and of the solutions implemented in this patch series. There you will also find some preliminary performance results. Thanks, Paolo [1] https://secure-web.cisco.com/1hcxnN1C3h1nW7mby7S66_LE8szirQwbQI0fBpYePr= A0GTWfyuQyl0GpZaOn32xMSkNT0BUQWloDHFzZ23aYDZdi8NfdrEFLY9pQDBblIvn08LRiTVoIO= UC8zWSG_r2PCyLtx3ppZq5cWOib_8azxteRRcbKWGdbLPSqg9hfSJSqltth0ByLONHEoI3p3e9Q= NIn6nVAeQbsT3aOQe-F95XrQvaPrFJXx6RGL9kDXyfkbXIHcdcLBf895gYBFn5S2WjBDQq2kzDz= ZOlc1HekRUhg0qDQcFY6NydVfrqNfLbpAHAth6KyREscQhVTMVREEVa1b6bQByX6grF5pn3pTIo= 0lODyfX6yRmcbReSYNfOZ65ZPvp-nH530FQ-5nXoRxFf74WIKDrNTALs3xQvg03DH4jLez-T2M9= xEu-sfEDAEdTGF7BcnmBW6vrPO4_p3k4/https%3A%2F%2Fwww.linaro.org%2Fblog%2Fbudg= et-fair-queueing-bfq-linux-io-scheduler-optimizations-for-multi-actuator-sa= ta-hard-drives%2F Davide Zini (3): block, bfq: split also async bfq_queues on a per-actuator basis block, bfq: inject I/O to underutilized actuators block, bfq: balance I/O injection among underutilized actuators Federico Gavioli (1): block, bfq: retrieve independent access ranges from request queue Paolo Valente (4): block, bfq: split sync bfq_queues on a per-actuator basis block, bfq: forbid stable merging of queues associated with different actuators block, bfq: turn scalar fields into arrays in bfq_io_cq block, bfq: turn BFQ_NUM_ACTUATORS into BFQ_MAX_ACTUATORS block/bfq-cgroup.c | 97 +++++---- block/bfq-iosched.c | 488 +++++++++++++++++++++++++++++--------------- block/bfq-iosched.h | 149 ++++++++++---- block/bfq-wf2q.c | 2 +- 4 files changed, 493 insertions(+), 243 deletions(-) -- 2.20.1 Seagate Internal Seagate Internal