The notifications from the DATE conference are in and the Memory Team scores 2 out of 2, just like in 2014. The first paper entitled “A Generic, Scalable and Globally Arbitrated Memory Tree for Shared DRAM Access in Real-Time Systems” was first-authored by Manil and is a collaboration with Jamie Garside and Neil Audsley from University of York. The paper proposes a memory interconnect for shared memory architectures in many-core systems. A main architectural feature is that the interconnect is heavily pipelined enabling it to be synthesized at high frequencies even with a large number of clients. Another highlight is that it has global arbitration that can be programmed to behave like several different arbitration mechanisms, such as TDM, CCSP and FBSP.
The second paper “Retention Time Measurements and Modelling of Bit Error Rates of WIDE I/O DRAM in MPSoCs”was first-authored by our colleagues at Kaiserslautern University of Technology in collaboration with Sven Goossens from our Memory Team. This paper looks into the thermal behavior of 3D-stacked WIDE I/O DRAM and compares its impact on retention time and bit error rates to conventional 2D DRAM chips.
A new version of the DRAMPower tool has been released. The two main features of version 4 are:
- DRAMPower can now be compiled as a library. This enables a user to access the tool through an API and log commands and their corresponding time stamps, removing the need to store large command traces on disk. The key benefit of this feature is that users can easily integrate DRAMPower into their own memory controller simulators and obtain power and energy consumption estimates. In fact, this version of DRAMPower is already integrated into the memory controller of the gem5 simulator system and is provided with the latest release.
- Improved robustness. The latest build is checked out every night on a test server, compiled, and tested to verify that the output matches an expected reference for a battery of tests. The code is also compiled with a large number of warning flags enabled and treats all warnings as errors. This feature makes it easier for the community to reliably contribute to the tool, which is now possible through github.
Check it out the new version of DRAMPower here.
The latest version of the tool now includes IO and Termination power measures from Micron’s DRAM Power Calculator for all supported DRAM generations. This feature enables support for power estimation of dual-rank DRAMs (DDR2/3/4). Additionally, new warning messages have been added, to identify if the memory or bank state is inconsistent in the user-defined command traces. This release also fixes minor bugs related to Precharge All (PREA) to improve the accuracy of DRAM power estimation.
Check it out here.
The new version of our tool for fast and accurate system-level power estimation of DRAMs has been released. This version features many important improvements, such as significantly improved analysis speed (at least 10x), enabling analysis of much larger traces, as well as support for LPDDR/LPDDR2 and Wide I/O memories. The results of this version have furthermore been verified by Kaiserslautern University of Technology using equivalent circuit-level SPICE simulations, which established that the error of the tool is < 2% for all memory operations of any granularity for all memories supported by DRAMPower.
For more information, or to download the tool, please refer to the official DRAMPower website.
For the second year in a row, Karthik Chandrasekar lands a paper at the prestigious Design Automation Conference (DAC). The paper is entitled “Towards Variation-Aware System-Level Power Estimation of DRAMs: An Empirical Approach” and discusses how to obtain more realistic power estimates with high-level power models by making them aware of process variation. Just like his recently accepted DATE paper, this work is a result of a successful collaboration with Christian Weis and Norbert Wehn at the University of Kaiserslautern.
Update: The paper is now available online. Click here to read it.
The preliminary author notification for DATE 2013 is now available on the conference website and it reveals that the memory team scores an incredible four accepted papers out of the four submitted, resulting in an acceptance ratio of 100% for the team! The four paper titles are:
The papers cover topics ranging from memory controller architectures, configuration, and power modeling for Wide I/O memories to open-page policies in real-time memory controllers and a comparison between the tightness of bounds for the latency-rate abstraction and cycle-accurate simulation. These papers are also evidence of the many recent successful collaborations as there are authors from CISTER-ISEP Research Unit, Fortiss, and the Technical Universities in Eindhoven, Kaiserslautern and Munich.
Today, we celebrate that Karthik Chandrasekar has received a 3 month HiPEAC collaboration grant to visit the group of Prof. Norbert Wehn at Kaiserslautern Institute of Technology. The application process was competitive with approximately 30% of 67 proposals being funded. The grant serves to extend the existing collaboration between our two groups and will be used to conduct research on the hot topic of “Mobile and 3D-Stacked Wide I/O DRAM Power Modeling and Optimization”.