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b=GpjSvDFe5lRAIeqHWDIBBWyHf1OHRGBDQ7bhub0QFDebAOsFzh70FEIcx5RvZfH7r 0nrxZf5lxFOg12w35V9l8CAAcii65TiwqLsjHboIQIyL0A6ayNFnV8EmgM2mUCr0bQ IXPM/FETVCxd9wW8cX437FFJJH8GPBRDyvb22PpHazj2UqBESet3Mw+uJuVJ0AS7Mu EXA/95xy7qAdjndGXlHoVu3xoSJP/IRgyGjl1bgqktOILtJluml4UXHcZl93orsFRl 7WyM637xCdThonphUZVjwykyzRc5iK1/AVMc47bro3GvDjXnG39RyNzRDxLUQBs6MP B4xWCc6EqRUmw== Received: by mail-pf1-f174.google.com with SMTP id d2e1a72fcca58-6d9bc8939d0so7677958b3a.0 for ; Wed, 17 Jan 2024 17:03:40 -0800 (PST) X-Gm-Message-State: AOJu0Yz6+ZsiG4ad5BxILG9GpdcfBH604SlBM4gesPxRf8JVM/6Nex/x n6dTf0tzpAhaL0cyqRUEFwLDOGCychaEa5hDDTARyoT13/z1ZNddaDxpC0bu6jWmfAS1pqwbnaQ vvlX1eO+8PwATTXj41RkJ/aOoueiBcV1AXJxk X-Google-Smtp-Source: AGHT+IGYCnVV6anRJS7ULoEj04u53JNIxkLyo79VW/gE+B+TNHO8kMJb3wPwo2UTJAbocSh7zkRDIIDqoQySTI9kKv4= X-Received: by 2002:a05:6a20:5530:b0:19a:4910:5716 with SMTP id ko48-20020a056a20553000b0019a49105716mr69166pzb.117.1705539819798; Wed, 17 Jan 2024 17:03:39 -0800 (PST) MIME-Version: 1.0 References: <20240117-b4-zswap-lock-optimize-v1-0-23f6effe5775@bytedance.com> In-Reply-To: From: Chris Li Date: Wed, 17 Jan 2024 17:03:27 -0800 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH 0/2] mm/zswap: optimize the scalability of zswap rb-tree To: Yosry Ahmed Cc: Chengming Zhou , Andrew Morton , linux-kernel@vger.kernel.org, Johannes Weiner , linux-mm@kvack.org, Nhat Pham Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspamd-Queue-Id: 55E4F180013 X-Rspam-User: X-Stat-Signature: ryf9fdzofu66hja36shw8kh495i6pqyy X-Rspamd-Server: rspam01 X-HE-Tag: 1705539825-38256 X-HE-Meta: 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 oEnT29Jx OJTjjpEbykB7y7qxGAMHwsW6AEmYTPYJaCfJuKbuWDSiqbLdTM+mqgrTmqV+39NAAXIBzg4HE2S/e5u2Q0abLUcj2TPBqmgsNt43AkyvbpyAQnhmwz9H45L2WmsTNVd7eeeUtigPeHQqflfrbYHrE+GOaO+brxNnSp8ZGdCNmDqrC22+u6qQ8fg6l51L1E/DnsX/UrlL2JSboVUvukTJqald2EHO2dAxOfyX8XfJBa7YnH2w= 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: List-Subscribe: List-Unsubscribe: Hi Yosry, On Wed, Jan 17, 2024 at 4:35=E2=80=AFPM Yosry Ahmed = wrote: > Hmm I don't understand. What's the point of keeping the rbtree if we > have the xarray? Doesn't it end up being more expensive and bug-prone > to maintain both trees? Patch 2/2 remove the rb tree code. Just keeping the tree spinlock. > > When you say "eventual goal", do you mean what the patch would morph > into in later versions (as in v1 is just a proof of concept without > removing the rbtree), or follow up patches? V1 will remove the rb tree, but does not merge the rb tree lock with the xarray lock. Hi Nhat, > Hmmm why? Is there a reason to keep the rb tree around? No, not at all. Chris