From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id E9DD8C25B08 for ; Sat, 13 Aug 2022 07:23:44 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id E97C88E0001; Sat, 13 Aug 2022 03:23:43 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id E21AF6B0075; Sat, 13 Aug 2022 03:23:43 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id CC1338E0001; Sat, 13 Aug 2022 03:23:43 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id B66AC6B0073 for ; Sat, 13 Aug 2022 03:23:43 -0400 (EDT) Received: from smtpin19.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay05.hostedemail.com (Postfix) with ESMTP id 8776440A75 for ; Sat, 13 Aug 2022 07:23:43 +0000 (UTC) X-FDA: 79793729526.19.6DDAFB0 Received: from frasgout.his.huawei.com (frasgout.his.huawei.com [185.176.79.56]) by imf08.hostedemail.com (Postfix) with ESMTP id E58141601AC for ; Sat, 13 Aug 2022 07:23:41 +0000 (UTC) Received: from fraeml705-chm.china.huawei.com (unknown [172.18.147.206]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4M4X350TN8z67TNp; Sat, 13 Aug 2022 15:18:57 +0800 (CST) Received: from lhrpeml500003.china.huawei.com (7.191.162.67) by fraeml705-chm.china.huawei.com (10.206.15.54) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2375.24; Sat, 13 Aug 2022 09:23:37 +0200 Received: from [10.48.145.22] (10.48.145.22) by lhrpeml500003.china.huawei.com (7.191.162.67) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Sat, 13 Aug 2022 08:23:36 +0100 Message-ID: <2b900d3b-9b52-5bc3-4ba8-24249f3c2e42@huawei.com> Date: Sat, 13 Aug 2022 08:23:36 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.6.1 Subject: Re: [ata] 0568e61225: stress-ng.copy-file.ops_per_sec -15.0% regression To: Damien Le Moal , Oliver Sang CC: Christoph Hellwig , "Martin K. Petersen" , LKML , "Linux Memory Management List" , , , , , , , References: <1f498d4a-f93f-ceb4-b713-753196e5e08d@opensource.wdc.com> <3451fa5a-6229-073f-ae18-0c232cd48ed5@huawei.com> <2e9cf5a6-c043-5ccf-e363-097c6c941891@huawei.com> <4642848c-a386-d6a0-6255-8b16800e0548@opensource.wdc.com> <840a5f98-a53c-ce08-2833-f41d8c9a015b@opensource.wdc.com> From: John Garry In-Reply-To: <840a5f98-a53c-ce08-2833-f41d8c9a015b@opensource.wdc.com> Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [10.48.145.22] X-ClientProxiedBy: lhrpeml100001.china.huawei.com (7.191.160.183) To lhrpeml500003.china.huawei.com (7.191.162.67) X-CFilter-Loop: Reflected ARC-Authentication-Results: i=1; imf08.hostedemail.com; dkim=none; dmarc=pass (policy=quarantine) header.from=huawei.com; spf=pass (imf08.hostedemail.com: domain of john.garry@huawei.com designates 185.176.79.56 as permitted sender) smtp.mailfrom=john.garry@huawei.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1660375422; a=rsa-sha256; cv=none; b=q7G2wzBG1f+2XTqv2sBHIegtduzgbYatwU2k+QxtKPQVpTjEtJOSOOtod+l73fN/v9XDQX unMLX6khSRMAlDT5tTZTPAqcjbiBn++KF6TOUmn+7ZwsL3UVnMF2fTy72RCisxHoM6KubY fD9XXXQrlA+Gb/2+2hpT4Scb8cqydqw= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1660375422; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=I1SOaHopBBvTwKejGH+F3UcxMCFsb1T0Qf1hkPyv2Ug=; b=DDzJ2GAlOH3MKpcjQhjQ8+6XPApHVpBGKM3ArxGLpQPL3Rpr3Gf6HHTXA4T/D0U+ucj1RT W7Phlgx6gyP2v7G+22/PxLG0Y2g2+Eky20U7tZlnFg/cAUDXYmcGYKuXJcfBZWoGj2k45d xhyNsr6djOyrnvMBPfO9MbNsAkshA8Y= X-Rspam-User: Authentication-Results: imf08.hostedemail.com; dkim=none; dmarc=pass (policy=quarantine) header.from=huawei.com; spf=pass (imf08.hostedemail.com: domain of john.garry@huawei.com designates 185.176.79.56 as permitted sender) smtp.mailfrom=john.garry@huawei.com X-Stat-Signature: 1rnq5gdgujybrzqdfcmt9jg9hecddryg X-Rspamd-Server: rspam11 X-Rspamd-Queue-Id: E58141601AC X-HE-Tag: 1660375421-183129 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On 12/08/2022 19:27, Damien Le Moal wrote: >> Interestingly ata dev max_sectors kb also gets capped from 32MB (LBA48) >> -> 256KB due to swiotlb max mapping size. (It would be capped by shost >> default max sectors 512KB without that swiotlb limit). I assume capping >> due to swiotlb limit is not occuring on Oliver's machine. > Yes, I was suspecting that we may be seeing a difference for anything that is > not AHCI, e.g. with other drivers. > > But that seems to be the correct thing to do, no ? Yes, this should be the correct thing to do. > How was this working before > without applying the swiotlb limit ? > Not sure. I would need to check the libata code for how it handles DMA mapping errors, which I assume would occur for when we exceed the swiotlb limit. Having said this, from limited testing, whenever I check megaraid sas or mpt3sas for performance, the length of request data never/rarely comes close to max sectors. That why I am surprised with the regression which Oliver reports. Thanks, John