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Thu, 15 Jan 2026 20:16:09 +0000 From: Date: Thu, 15 Jan 2026 12:16:06 -0800 To: "David Hildenbrand (Red Hat)" , Jonathan Cameron CC: Li Zhe , , , , , , , , , , , , , Davidlohr Bueso , Gregory Price , Dan Williams , , Message-ID: <69694b06835e_34d2a100b3@dwillia2-mobl4.notmuch> In-Reply-To: <23513e86-0769-4f3f-b90b-22273343a03c@kernel.org> References: <9daa39e6-9653-45cc-8c00-abf5f3bae974@kernel.org> <20260115093641.44404-1-lizhe.67@bytedance.com> <83798495-915b-4a5d-9638-f5b3de913b71@kernel.org> <20260115115739.00007cf6@huawei.com> <23513e86-0769-4f3f-b90b-22273343a03c@kernel.org> Subject: Re: [PATCH v2 0/8] Introduce a huge-page pre-zeroing mechanism Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-ClientProxiedBy: BY3PR05CA0058.namprd05.prod.outlook.com (2603:10b6:a03:39b::33) To PH8PR11MB8107.namprd11.prod.outlook.com (2603:10b6:510:256::6) Precedence: bulk X-Mailing-List: linux-cxl@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: PH8PR11MB8107:EE_|MW3PR11MB4732:EE_ X-MS-Office365-Filtering-Correlation-Id: af3ea222-2abf-45f6-f615-08de5472ec07 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|7416014|1800799024|366016|376014; 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In the case of this patch there is no async-offload benefit because userspace is already charged with spawning more threads if it wants more parallelism. For sync-offload one engine may be able to beat a single CPU, but now you have created bandwidth contention problems with a component that is less responsive to the scheduler. Call me skeptical. Signed, someone with async_tx and dmaengine battle scars.