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X-CSE-ConnectionGUID: o026d4LcRFij9dOYZPHS0w== X-CSE-MsgGUID: 6iNNUzsXRx+lHGoTlJrZbw== X-IronPort-AV: E=McAfee;i="6800,10657,11852"; a="84898525" X-IronPort-AV: E=Sophos;i="6.25,174,1779174000"; d="scan'208";a="84898525" Received: from orviesa001.jf.intel.com ([10.64.159.141]) by orvoesa112.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 20 Jul 2026 06:05:08 -0700 X-CSE-ConnectionGUID: 9Eb9vpu/RaeFxpiW+w8L1Q== X-CSE-MsgGUID: TX930MbuTsSLX0njsjivxQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.25,174,1779174000"; d="scan'208";a="295658442" Received: from bradocaj-mobl.ger.corp.intel.com (HELO [10.125.109.156]) ([10.125.109.156]) by smtpauth.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 20 Jul 2026 06:05:07 -0700 Message-ID: <33fae97d-75db-4df7-9aa3-05a51f8747cd@intel.com> Date: Mon, 20 Jul 2026 06:05:06 -0700 Precedence: bulk X-Mailing-List: linux-arch@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v7 0/9] mm: optimize zone-device memmap initialization To: Li Zhe , akpm@linux-foundation.org, apopple@nvidia.com, arnd@arndb.de, balbirs@nvidia.com, bp@alien8.de, dave.hansen@linux.intel.com, david@kernel.org, kees@kernel.org, mingo@redhat.com, rppt@kernel.org, tglx@kernel.org, muchun.song@linux.dev Cc: linux-arch@vger.kernel.org, linux-hardening@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, x86@kernel.org References: <20260720120259.1545-1-lizhe.67@bytedance.com> From: Dave Hansen Content-Language: en-US Autocrypt: addr=dave.hansen@intel.com; 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charset=UTF-8 Content-Transfer-Encoding: 7bit On 7/20/26 05:02, Li Zhe wrote: > This reduces the average memmap initialization time measured during > rebind by about 60.4% for nd_pmem and 56.4% for dax_pmem. There are lots of things in the kernel we could optimize. Why is this important?