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Sat, 13 Jun 2026 03:10:44 -0700 (PDT) Received: from localhost.localdomain ([157.15.11.68]) by smtp.gmail.com with ESMTPSA id d2e1a72fcca58-8434b00d3f9sm4111908b3a.41.2026.06.13.03.10.42 (version=TLS1_3 cipher=TLS_CHACHA20_POLY1305_SHA256 bits=256/256); Sat, 13 Jun 2026 03:10:44 -0700 (PDT) From: Nithurshen To: hsiangkao@linux.alibaba.com Cc: linux-erofs@lists.ozlabs.org, nithurshen.dev@gmail.com, xiang@kernel.org Subject: Re: [PATCH v1] fsck.erofs: implement thread-safe global LRU metadata cache Date: Sat, 13 Jun 2026 15:40:38 +0530 Message-ID: <20260613101038.86333-1-nithurshen.dev@gmail.com> X-Mailer: git-send-email 2.52.0 In-Reply-To: <423c662c-e8b4-4802-b7bf-34abd71a82ae@linux.alibaba.com> References: <423c662c-e8b4-4802-b7bf-34abd71a82ae@linux.alibaba.com> X-Mailing-List: linux-erofs@lists.ozlabs.org List-Id: List-Help: List-Owner: List-Post: List-Subscribe: , , List-Unsubscribe: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Hi Xiang, What if rather than caching the raw metadata bytes, the userspace cache will focus on caching the parsed structures (such as the computed erofs_map_blocks mappings) to save the worker threads from redundantly parsing chunk indexes and calculating offsets. Can I replace this malloc-based raw buffer approach and focus v3 patch on an LRU cache for the parsed block mappings to reduce the CPU overhead during the concurrent directory traversal? Thanks, Nithurshen