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arXiv · 2510.15744

Cleaning up the Mess: Re-Evaluating the Real-System Modeling Accuracy of Ramulator 2.0

F. Nisa Bostanci·Haocong Luo·Ataberk Olgun·Maria Makeenkova·Geraldo F. Oliveira·A. Giray Yaglikci·Onur Mutlu
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Abstract

A MICRO 2024 best paper runner-up publication (the Mess paper) with all three artifact badges awarded (including ``Reproducible'') proposes a new benchmark to evaluate real and simulated memory system performance. The publication contends that Ramulator 2.0 and DAMOV (ZSim+Ramulator) (along with other existing memory system simulators) ``poorly resemble the actual system performance'' and asserts that their simulator is better. In this paper, we show that the Mess paper has 1) demonstrable technical misconfigurations, 2) methodological errors in interpreting simulation statistics, and 3) an incomplete artifact that makes its key results irreproducible. We demonstrate that the Ramulator 2.0 simulation results reported in the Mess paper are incorrect due to multiple configuration errors instead of inherent simulation inaccuracy claimed by the Mess paper. We show that by correctly configuring Ramulator 2.0, Ramulator 2.0's simulated memory system performance actually resembles real system characteristics well, and thus a key claimed contribution of the Mess paper is factually incorrect. We also identify that the DAMOV simulation results in the Mess paper use wrong simulation statistics that are unrelated to the simulated DRAM performance. We show that DAMOV's simulated DRAM latency is not constant, in contrast to the Mess paper's claim. Moreover, the Mess paper's artifact repository lacks the necessary sources to fully reproduce all the Mess paper's results. We find that the experiment scripts use simulator executables and other resources that are neither described in the Mess paper nor found in the artifact repository. We strongly encourage the computer architecture community to consider our corrections to the Ramulator 2.0 and DAMOV results of the Mess paper to prevent the propagation of inaccurate and misleading results and to maintain the reliability of the scientific record.

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F. Nisa Bostanci, Haocong Luo, Ataberk Olgun, Maria Makeenkova, Geraldo F. Oliveira, A. Giray Yaglikci, Onur Mutlu. 2025-10-17. Cleaning up the Mess: Re-Evaluating the Real-System Modeling Accuracy of Ramulator 2.0. https://arxiv.org/abs/2510.15744

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