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Energy-Optimized On-Chip Networks Using Reconfigurable Shortcut Paths [chapter]

Nasibeh Teimouri, Mehdi Modarressi, Arash Tavakkol, Hamid Sarbazi-azad
2011 Lecture Notes in Computer Science  
Topology is an important network attribute that greatly affects the power, performance, cost, and design time/effort of NoCs. In this paper, we propose a novel NoC architecture that can exploit the benefits of both application-specific and regular NoC topologies. To this end, a subset of NoC links bypass the router pipeline stages and directly connect remotely located nodes. This results in an NoC which holds both fixed connections between adjacent nodes and long connections virtually
more » ... non-adjacent nodes. These shortcut paths are constructed at run-time by employing a simple and fast mechanism composed of two processes: on-chip traffic monitoring and path reconfiguration. The former keeps the track of the changes in the on-chip traffic pattern and detects high-volume communication flows. The latter then adapts the shortcut paths to the current on-chip traffic pattern by constructing shortcut paths between the source and destination nodes of the high-volume communication flows. Supporting the shortcut paths imposes a trivial overhead on the area of a conventional packet-switched router. Experimental results reveal the effectiveness of the proposed technique in reducing the energy consumption and improving the performance of NoCs.
doi:10.1007/978-3-642-19137-4_20 fatcat:46q5bfplsrcrtnmjbisdyjcvr4

Design for scalability in enterprise SSDs

Arash Tavakkol, Mohammad Arjomand, Hamid Sarbazi-Azad
2014 Proceedings of the 23rd international conference on Parallel architectures and compilation - PACT '14  
To cope with this issue, Tavakkol et al. [50] suggested to leverage a network-based controller-to-flash communication structure.  ...  Recently, Tavakkol et al. proposed a more generic and regular network-based design paradigm, namely Network-on-SSD (NoSSD) [50] , which showed significant performance over conventional designs.  ... 
doi:10.1145/2628071.2628098 dblp:conf/IEEEpact/TavakkolAS14 fatcat:sszdx6zo25ha5pbuycrcejwwhm

Enabling Efficient RDMA-based Synchronous Mirroring of Persistent Memory Transactions [article]

Arash Tavakkol, Aasheesh Kolli, Stanko Novakovic, Kaveh Razavi, Juan Gomez-Luna, Hasan Hassan, Claude Barthels, Yaohua Wang, Mohammad Sadrosadati, Saugata Ghose, Ankit Singla, Pratap Subrahmanyam, Onur Mutlu
2018 arXiv   pre-print
Synchronous Mirroring (SM) is a standard approach to building highly-available and fault-tolerant enterprise storage systems. SM ensures strong data consistency by maintaining multiple exact data replicas and synchronously propagating every update to all of them. Such strong consistency provides fault tolerance guarantees and a simple programming model coveted by enterprise system designers. For current storage devices, SM comes at modest performance overheads. This is because performing both
more » ... cal and remote updates simultaneously is only marginally slower than performing just local updates, due to the relatively slow performance of accesses to storage in today's systems. However, emerging persistent memory and ultra-low-latency network technologies necessitate a careful re-evaluation of the existing SM techniques, as these technologies present fundamentally different latency characteristics compared than their traditional counterparts. In addition to that, existing low-latency network technologies, such as Remote Direct Memory Access (RDMA), provide limited ordering guarantees and do not provide durability guarantees necessary for SM. To evaluate the performance implications of RDMA-based SM, we develop a rigorous testing framework that is based on emulated persistent memory. Our testing framework makes use of two different tools: (i) a configurable microbenchmark and (ii) a modified version of the WHISPER benchmark suite, which comprises a set of common cloud applications. Using this framework, we find that recently proposed RDMA primitives, such as remote commit, provide correctness guarantees, but do not take full advantage of the asynchronous nature of RDMA hardware. To this end, we propose new primitives enabling efficient and correct SM over RDMA, and use these primitives to develop two new techniques delivering high-performance SM of persistent memories.
arXiv:1810.09360v1 fatcat:l3u2vf7p5neufflz7cl6okq3q4

The Effect of Network Topology and Channel Labels on the Performance of Label-Based Routing Algorithms [chapter]

Reza Moraveji, Hamid Sarbazi-Azad, Arash Tavakkol
2008 Lecture Notes in Computer Science  
Designing an efficient deadlock-free routing is a point of concern for irregular topologies. In this paper, we take a step toward the goal by developing three novel deadlock-free routing algorithms in the content of a new family of algorithms called label-based routing algorithms for irregular topologies. In addition, the newly proposed family covers three previously reported routing algorithms [2, 3] . Moreover, by simulating and comparing the newly and traditional proposed routing methods, it
more » ... is shown that the performance of this family highly depends on the network topology and channel labeling process.
doi:10.1007/978-3-540-69384-0_58 fatcat:6lsixmn4mzbxbibtmufqvxhfem

MQSim: A Framework for Enabling Realistic Studies of Modern Multi-Queue SSD Devices

Arash Tavakkol, Juan Gómez-Luna, Mohammad Sadrosadati, Saugata Ghose, Onur Mutlu
2018 USENIX Conference on File and Storage Technologies  
Solid-state drives (SSDs) are used in a wide array of computer systems today, including in datacenters and enterprise servers. As the I/O demands of these systems continue to increase, manufacturers are evolving SSD architectures to keep up with this demand. For example, manufacturers have introduced new high-bandwidth interfaces to replace the conventional SATA host-interface protocol. These new interfaces, such as the NVMe protocol, are designed specifically to enable the high amounts of
more » ... rrent I/O bandwidth that SSDs are capable of delivering. While modern SSDs with sophisticated features such as the NVMe protocol are already on the market, existing SSD simulation tools have fallen behind, as they do not capture these new features. We find that state-of-theart SSD simulators have three shortcomings that prevent them from accurately modeling the performance of real off-the-shelf SSDs. First, these simulators do not model critical features of new protocols (e.g., NVMe), such as their use of multiple application-level queues for requests and the elimination of OS intervention for I/O request processing. Second, these simulators often do not accurately capture the impact of advanced SSD maintenance algorithms (e.g., garbage collection), as they do not properly or quickly emulate steady-state conditions that can significantly change the behavior of these algorithms in real SSDs. Third, these simulators do not capture the full end-to-end latency of I/O requests, which can incorrectly skew the results reported for SSDs that make use of emerging non-volatile memory technologies. By not accurately modeling these three features, existing simulators report results that deviate significantly from real SSD performance. In this work, we introduce a new simulator, called MQSim, that accurately models the performance of both modern SSDs and conventional SATA-based SSDs. MQSim faithfully models new high-bandwidth protocol implementations, steady-state SSD conditions, and the full end-to-end latency of requests in modern SSDs. We validate MQSim, showing that it reports performance results that are only 6%-18% apart from the measured actual performance of four real state-of-the-art SSDs. We show that by modeling critical features of modern SSDs, MQSim uncovers several real and important issues that were not captured by existing simulators, such as the performance impact of inter-flow interference. We have released MQSim as an open-source tool, and we hope that it can enable researchers to explore directions in new and different areas.
dblp:conf/fast/TavakkolGSGM18 fatcat:zcewyum2uracdgy2pvjbuxtewy

Performance Evaluation of Dynamic Page Allocation Strategies in SSDs

Arash Tavakkol, Pooyan Mehrvarzy, Mohammad Arjomand, Hamid Sarbazi-Azad
2016 ACM Transactions on Modeling and Performance Evaluation of Computing Systems  
Variations of this methodology were used in previous studies for IOPS calculation [Narayanan et al. 2009; Wu and He 2012; Grupp et al. 2013] , whereas exactly the same method was already used in Tavakkol  ... 
doi:10.1145/2829974 fatcat:3xf5nou7u5dcvesl6ozq4tvhky

Dataplant: Enhancing System Security with Low-Cost In-DRAM Value Generation Primitives [article]

Lois Orosa, Yaohua Wang, Ivan Puddu, Mohammad Sadrosadati, Kaveh Razavi, Juan Gómez-Luna, Hasan Hassan, Nika Mansouri-Ghiasi, Arash Tavakkol, Minesh Patel, Jeremie Kim, Vivek Seshadri (+4 others)
2019 arXiv   pre-print
DRAM manufacturers have been prioritizing memory capacity, yield, and bandwidth for years, while trying to keep the design complexity as simple as possible. DRAM chips do not carry out any computation or other important functions, such as security. Processors implement most of the existing security mechanisms that protect the system against security threats, because 1) executing security mechanisms usually require non-trivial computational capabilities (e.g., encryption), and 2) commodity DRAM
more » ... hips are not designed to perform computations or tasks other than data storage. In this work, we advocate for DRAM as a key component for providing security mechanisms to the system. To this end, we propose Dataplant, a new class of low-cost, high-performance, and reliable security primitives that can be integrated in commodity DRAM chips with minimal changes. The main idea of Dataplant is to slightly modify the internal DRAM timing signals to expose the inherent process variation found in all DRAM chips for generating unpredictable but reproducible values (e.g., keys) within DRAM. We use Dataplant to build two new security mechanisms. First, a new Dataplant-based physical unclonable function (PUF) with non-destructive read-out, low evaluation latency, robust responses, resiliency to temperature changes, and data-independent responses. Second, a new cold boot attack prevention mechanism that automatically destroys all data within DRAM on every power cycle with zero run-time energy and latency overheads. Using a combination of detailed simulations and experiments with 136 real commodity DRAM chips, we show that our Dataplant-based PUF has 1.8x higher throughput than the best state-of-the-art DRAM PUFs. We also demonstrate that our Dataplant-based cold boot attack protection mechanism is 19.5x faster and consumes 2.54x less energy when compared to existing mechanisms.
arXiv:1902.07344v2 fatcat:rpfx6htqjfbhtjirzjy76rbbia

PDP 2020 Committees

2020 2020 28th Euromicro International Conference on Parallel, Distributed and Network-Based Processing (PDP)  
Zarandi Amirali Baniasadi Dara Rahmati Hossein Asadi Mehdi Modarressi Pejman Lotfi-Kamran Marjan Asadinia Mohammad Arjomand Saeid Gorgin Diana Goehringer Farshad Khunjush Arash Tavakkol Farhad  ...  Tavakkol Program Committee Ahmad Khonsari Mohammad Sadr Hamid R.  ... 
doi:10.1109/pdp50117.2020.00007 fatcat:plmo7ph7iff55pylwt4oqqsqfm

Inhibition of Digestive α-Amylases from Chilo Suppressalis Walker (Lepidoptera: Crambidae) by a Proteinaceous Extract of Citrullus Colocynthis L. (Cucurbitaceae)

Bita Valizadeh, Arash Zibaee, Jalal Jalali Sendi
2013 Journal of Plant Protection Research  
The extract has anti-virus as well as anti-cancer properties (Tavakkol-Afshari et al. 2005) .  ...  (Cucurbitaceae), known as bitter apple, vine-of-Sodom, tumba or wild gourd (Tavakkol-Afshari et al. 2005) .  ... 
doi:10.2478/jppr-2013-0030 fatcat:3pwqzd3k4nbfxmhlxp7fr6ja4a

Tribulus terrestris

2013 Reactions weekly  
Afshari 2* , Hamid Rahimian Mashhadi 3 and Arash Mamedi 4 1, 3, 4.  ...  بیش‬ ‫بهینۀ‬ ‫و‬ ‫پایین)‬ ‫(مطلوب‬ ‫کم‬ ‫بهینۀ‬ ‫(پایه)،‬ ‫کمینه‬ ‫دماهای‬ ‫آن‬ ‫در‬ ‫که‬ ‫بود‬ ‫مانند‬ ‫دندان‬ ‫مدل‬Cardinal temperatures for germination of Tribulus terrestrisAhmad Sarmadi 1 , Reza Tavakkol  ... 
doi:10.1007/s40278-013-7542-4 fatcat:tfq4rp4esjda3pdvlufdvvzwpe

Callus induction and plant regeneration of Valeriana officinalis are affected by different leaf explants and various concentrations of plant growth regulators

Akram Zamini, Arash Mokhtari, Minoo Tansaz, Mohsen Zarei
2016 BioTechnologia  
and cell division were stimulated faster and better in rapeseed cultivars when 2,4-D was combined with a cytokinin (BA), NAA (with or without BA), however, stimulated root formation and rhizogenesis (Tavakkol  ... 
doi:10.5114/bta.2016.64543 fatcat:jmuxxj7eing7za34glgvgsznwu

Considering Pricing Problem in a Dynamic and Integrated Design of Sustainable Closed-loop Supply Chain Network

Arash Nobari, Saman Kheirkhah, Maryam Esmaeili
2016 International Journal of Industrial Engineering and Production Research  
., centers dependen Productio (2008), P 20] Dehghan sustainab products Resource Vol. 53, ( 21] Tuzkaya methodol reverse lo in the Internatio Research 4543-457 22] Tavakkol & Molla-  ... 
doaj:dd1bd5f883334a71990151092e12c6a7 fatcat:iuv6esujbjbbbe5ljvmqqnebum

CODIC: A Low-Cost Substrate for Enabling Custom In-DRAM Functionalities and Optimizations [article]

Lois Orosa, Yaohua Wang, Mohammad Sadrosadati, Jeremie S. Kim, Minesh Patel, Ivan Puddu, Haocong Luo, Kaveh Razavi, Juan Gómez-Luna, Hasan Hassan, Nika Mansouri-Ghiasi, Saugata Ghose (+1 others)
2021 arXiv   pre-print
We thank Uksong Kang, Vivek Seshadri, and Arash Tavakkol for their feedback and suggestions on earlier versions of this paper.  ... 
arXiv:2106.05632v1 fatcat:57kx6f3cibckzgcbuz3dcbnosa

Prediction and classification of sugar content of sugarcane based on skin scanning using visible and shortwave near infrared

Nazmi Mat Nawi, Guangnan Chen, Troy Jensen, Saman Abdanan Mehdizadeh
2013 Biosystems Engineering  
SEED DRYING CONDITIONS WITH RESPONSE SURFACE METHODOLOGY IN A CONSTANT-BED DRYER USING TWO CULTIVARS Reza Tavakkol Afshari Ali Abbasi Surki; Reza Tavakkol Afshari P-0124 EFFECT OF EDIBLE COATING ON THE  ...  Joo Kim, Seong Il Kang, Joonyong Kim P-0844 OPTIMAL SELECTION OF FARM POWER AND MACHINERY SIZE BY MIXED INTE- GER LINEAR PROGRAMMING Rajab Tondro Rajab Tondro, Hasan Aghel, Mahdi Kho- jastepour, Arash  ... 
doi:10.1016/j.biosystemseng.2013.03.005 fatcat:onnkzfpj3nghbam57r7mbmzs6e