Top AI Repos — open-source AI, indexed and scored

Top AI Repos tracks AI repositories on GitHub and answers two different questions about each one: is it moving right now, and would you bet a product on it.

CMU-SAFARI/ramulator2

Ramulator 2.0 is a modern, modular, extensible, and fast cycle-accurate DRAM simulator. It provides support for agile implementation and evaluation of new memory system designs (e.g., new DRAM standards, emerging RowHammer mitigation techniques). Described in our IEEE CAL 2023 paper: https://arxiv.org/pdf/2308.11030.

72MITC++

Star history, last 90 days
Date	Stars
2026-07-25	605
2026-07-28	605
2026-07-30	605
2026-08-06	605

Star history, last 90 days

Date

Stars

2026-07-25

605

2026-07-28

605

2026-07-30

605

2026-08-06

605

# Ramulator 2.1 User Guide - [1. Overview](#1-overview) - [2. Using Ramulator 2.1](#2-using-ramulator-21) - [3. Your First Run](#3-your-first-run) - [4. Writing Configurations](#4-writing-configurations) - [5. Validation and Regression Tests](#5-validation-and-regression-tests) - [6. gem5 Integration](#6-gem5-integration) - [7. Using Ramulator as a pure C++ Library](#7-using-ramulator-as-a-pure-c-library) - [8. Extending Ramulator](#8-extending-ramulator) - [9. How Ramulator Works Internally](#9-how-ramulator-works-internally) - [10. Trace Visualizer](#10-trace-visualizer) ## 1. Overview ### 1.1 Introduction Ramulator 2.1 is a modern, modular, and extensible cycle-level DRAM simulator. It is the successor of Ramulator 1.0 [Kim+, CAL'16] and a major overhaul of Ramulator 2.0 [Luo+, CAL'23]. The goal of Ramulator 2.1 is to enable rapid and agile implementation and evaluation of design changes in the memory controller and DRAM to meet the increasing research effort in improving the performance, security, and reliability of memory systems. Ramulator 2.1 features a clean and modular C++ codebase with automatically generated Python wrappers that enables easy and scriptable configurations and extensions. Users can focus just on the C++ code that implements modeling and simulation logic without having to worry about manually maintaining boilerplate code. Ramulator 2.1 can either be used as a standalone simulator that takes memory traces, or be easily integrated into other simulators as a DRAM and memory controller simulation library. We currently provide gem5 wrappers that works as a drop-in component for both SE and FS mode (tested with gem5 v25.1, FS mode tested with a post-boot checkpoint). This Github repository contains the public version of Ramulator 2.1. From time to time, we will synchronize improvements of the code framework, additional functionalities, bug fixes, etc. from our internal version. Ramulator 2.1 welcomes your contribution as well as new ideas and implementations in the memory system. Currently, Ramulator 2.1 provides the DRAM device and memory controller models for the following standards: - DDR3, DDR4, DDR5 - GDDR6, GDDR7 - LPDDR5, LPDDR6 - HBM1, HBM2, HBM3, HBM4 What has changed from Ramulator 2.0: - Aggregated bug fixes - More comprehensive support for newer DRAM & controller features - More comprehensive sets of test and validation workflows - Significantly improved the ease of use, configuration, and extension - Overall code quality improvements ### 1.2 Repository Layout - `src/` C++ code for main simulator implementation. - `python/` Python wrappers for easy and scriptable configuration of Ramulator. - `examples/` Ready-to-run example configurations and traces. - `tests/` Tests and validation workflows. - `resources/gem5_wrappers/` Reference wrapper code for gem5 integration. - `visualizer/` Browser-based trace visualizer (Nuxt/WebGL). See [Section 10](#10-trace-visualizer). ## 2. Using Ramulator 2.1 We highly recommend to use our container (Dockerfile available at `.devcontainer/Dockerfile`) to avoid any dependency issues. The repository is also configured to be able to be one-click opened as a Dev Container with all the dependencies already installed. The easiest way to start using and developing Ramulator 2.1 is to directly create a Codespace on the GitHub page of the Ramulator 2.1 repository. If you are using Visual Studio Code, it should automatically prompt you to reopen the repository in a Dev Container after you clone and open the repo for the first time. If you want to set up the container locally, you can do the following steps: ```bash docker compose up -d --build docker compose exec ramulator2 bash ``` Doing so creates a container with all the dependencies, mounts the Ramulator 2.1 repository at `/workspace`, and automatically activates `ramulator2-venv` in the container bash. If you need to configure your own environment, please refer to Section 2.3 for detailed instr