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J . Mercier" , Baolin Wang , Suren Baghdasaryan , Meta kernel team , bpf@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [LSF/MM/BPF TOPIC] Towards Unified and Extensible Memory Reclaim (reclaim_ext) Message-ID: References: <20260325210637.3704220-1-shakeel.butt@linux.dev> <20260325190547.abb7309fb63473b57b7a90a0@linux-foundation.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Thu, Mar 26, 2026 at 01:02:02PM -0700, Axel Rasmussen wrote: > > I think one thing we all agree on at least is, long term, there isn't > really a good argument for having > 1 LRU implementation. E.g., we > don't believe there are just irreconcilable differences, where one > impl is better for some workloads, and another is better for others, > and there is no way the two can be converged. > I absolutely believe there are irreconcilable differences - but not in the sense that one is better or worse, but in the sense that features from one cannot work in the other. > - My sense is MGLRU is "close", meaning as Kairui said in "average" > cases it is substantially better, and the gaps are both fairly narrow > / edge-casey, and very solveable. > This is a really, really bold claim. So much of this is workload dependent, and LRU has decades of battle-testing while MGLRU has barely been around 4 years. ~Gregory