30 research outputs found
A Survey on Automatic Parameter Tuning for Big Data Processing Systems
Big data processing systems (e.g., Hadoop, Spark, Storm) contain a vast number of configuration parameters controlling parallelism, I/O behavior, memory settings, and compression. Improper parameter settings can cause significant performance degradation and stability issues. However, regular users and even expert administrators grapple with understanding and tuning them to achieve good performance. We investigate existing approaches on parameter tuning for both batch and stream data processing systems and classify them into six categories: rule-based, cost modeling, simulation-based, experiment-driven, machine learning, and adaptive tuning. We summarize the pros and cons of each approach and raise some open research problems for automatic parameter tuning.Peer reviewe
Volunteer computing
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2001.Includes bibliographical references (p. 205-216).This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.This thesis presents the idea of volunteer computing, which allows high-performance parallel computing networks to be formed easily, quickly, and inexpensively by enabling ordinary Internet users to share their computers' idle processing power without needing expert help. In recent years, projects such as SETI@home have demonstrated the great potential power of volunteer computing. In this thesis, we identify volunteer computing's further potentials, and show how these can be achieved. We present the Bayanihan system for web-based volunteer computing. Using Java applets, Bayanihan enables users to volunteer their computers by simply visiting a web page. This makes it possible to set up parallel computing networks in a matter of minutes compared to the hours, days, or weeks required by traditional NOW and metacomputing systems. At the same time, Bayanihan provides a flexible object-oriented software framework that makes it easy for programmers to write various applications, and for researchers to address issues such as adaptive parallelism, fault-tolerance, and scalability. Using Bayanihan, we develop a general-purpose runtime system and APIs, and show how volunteer computing's usefulness extends beyond solving esoteric mathematical problems to other, more practical, master-worker applications such as image rendering, distributed web-crawling, genetic algorithms, parametric analysis, and Monte Carlo simulations. By presenting a new API using the bulk synchronous parallel (BSP) model, we further show that contrary to popular belief and practice, volunteer computing need not be limited to master-worker applications, but can be used for coarse-grain message-passing programs as well. Finally, we address the new problem of maintaining reliability in the presence of malicious volunteers. We present and analyze traditional techniques such as voting, and new ones such as spot-checking, encrypted computation, and periodic obfuscation. Then, we show how these can be integrated in a new idea called credibility-based fault-tolerance, which uses probability estimates to limit and direct the use of redundancy. We validate this new idea with parallel Monte Carlo simulations, and show how it can achieve error rates several orders-of-magnitude smaller than traditional voting for the same slowdown.by Luis F.G. Sarmenta.Ph.D
Proceedings of the 5th International Workshop on Reconfigurable Communication-centric Systems on Chip 2010 - ReCoSoC\u2710 - May 17-19, 2010 Karlsruhe, Germany. (KIT Scientific Reports ; 7551)
ReCoSoC is intended to be a periodic annual meeting to expose and discuss gathered expertise as well as state of the art research around SoC related topics through plenary invited papers and posters. The workshop aims to provide a prospective view of tomorrow\u27s challenges in the multibillion transistor era, taking into account the emerging techniques and architectures exploring the synergy between flexible on-chip communication and system reconfigurability
Multi-level simulation of nano-electronic digital circuits on GPUs
Simulation of circuits and faults is an essential part in design and test validation tasks of contemporary nano-electronic digital integrated CMOS circuits.
Shrinking technology processes with smaller feature sizes and strict performance and reliability requirements demand not only detailed validation of the functional properties of a design, but also accurate validation of non-functional aspects including the timing behavior. However, due to the rising complexity of the circuit behavior and the steady growth of the designs with respect to the transistor count, timing-accurate simulation of current designs requires a lot of computational effort which can only be handled by proper abstraction and a high degree of parallelization.
This work presents a simulation model for scalable and accurate timing simulation of digital circuits on data-parallel graphics processing unit (GPU) accelerators.
By providing compact modeling and data-structures as well as through exploiting multiple dimensions of parallelism, the simulation model enables not only fast and timing-accurate simulation at logic level, but also massively-parallel simulation with switch level accuracy.
The model facilitates extensions for fast and efficient fault simulation of small delay faults at logic level, as well as first-order parametric and parasitic faults at switch level.
With the parallelization on GPUs, detailed and scalable simulation is enabled that is applicable even to multi-million gate designs.
This way, comprehensive analyses of realistic timing-related faults in presence of process- and parameter variations are enabled for the first time.
Additional simulation efficiency is achieved by merging the presented methods in a unified simulation model, that allows to combine the unique advantages of the different levels of abstraction in a mixed-abstraction multi-level simulation flow to reach even higher speedups.
Experimental results show that the implemented parallel approach achieves unprecedented simulation throughput as well as high speedup compared to conventional timing simulators.
The underlying model scales for multi-million gate designs and gives detailed insights into the timing behavior of digital CMOS circuits, thereby enabling large-scale applications to aid even highly complex design and test validation tasks
CROSS-LAYER DESIGN, OPTIMIZATION AND PROTOTYPING OF NoCs FOR THE NEXT GENERATION OF HOMOGENEOUS MANY-CORE SYSTEMS
This thesis provides a whole set of design methods to enable and manage the
runtime heterogeneity of features-rich industry-ready Tile-Based Networkon-
Chips at different abstraction layers (Architecture Design, Network Assembling,
Testing of NoC, Runtime Operation). The key idea is to maintain
the functionalities of the original layers, and to improve the performance
of architectures by allowing, joint optimization and layer coordinations. In
general purpose systems, we address the microarchitectural challenges by codesigning
and co-optimizing feature-rich architectures. In application-specific
NoCs, we emphasize the event notification, so that the platform is continuously
under control. At the network assembly level, this thesis proposes a
Hold Time Robustness technique, to tackle the hold time issue in synchronous
NoCs. At the network architectural level, the choice of a suitable synchronization
paradigm requires a boost of synthesis flow as well as the coexistence
with the DVFS. On one hand this implies the coexistence of mesochronous
synchronizers in the network with dual-clock FIFOs at network boundaries.
On the other hand, dual-clock FIFOs may be placed across inter-switch links
hence removing the need for mesochronous synchronizers. This thesis will
study the implications of the above approaches both on the design flow and
on the performance and power quality metrics of the network. Once the manycore
system is composed together, the issue of testing it arises. This thesis
takes on this challenge and engineers various testing infrastructures. At the
upper abstraction layer, the thesis addresses the issue of managing the fully
operational system and proposes a congestion management technique named
HACS. Moreover, some of the ideas of this thesis will undergo an FPGA
prototyping. Finally, we provide some features for emerging technology by
characterizing the power consumption of Optical NoC Interfaces
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A Computational Framework for Resilience-Informed Design
It is desirable for complex engineered systems to perform missions efficiently and economically, even when these missions' complex, variable, long-term operational profiles make it likely for hazards to arise. It is thus important to design these systems to be resilient so that they will actively prevent and recover from hazards when they occur. To most effectively design a system to be resilient, the resilience of each design alternative should be quantified and valued so that it can be incorporated in the decision-making process. However, considering resilience in early design is challenging because resilience is a dynamic and stochastic property characterizing how the system performs over time in a set of unlikely-but-salient hazardous scenarios. Quantifying these properties thus requires a model to simulate the system's dynamic behavior and performance over the set of hazardous scenarios. Thus, to be able to incorporate resilience in the design process, there is a need to develop a framework which implements and integrates these models with design exploration and decision-making. This dissertation fulfills this need by defining resilience to enable fault simulations to be incorporated in decision-making, devising and implementing a modelling framework for early assessment of system resilience attributes, and exploring optimization architectures to efficiently structure the design exploration of resilience variables. Additionally, this dissertation provides a validity testing framework to determine when the resilient design process has been effective given the uncertainties present in the design problem. When each of these parts are used together, they comprise an overall framework that can be used to consider and incorporate system resilience in the early design process
Methodologies and Toolflows for the Predictable Design of Reliable and Low-Power NoCs
There is today the unmistakable need to evolve design methodologies and
tool
ows for Network-on-Chip based embedded systems. In particular, the
quest for low-power requirements is nowadays a more-than-ever urgent dilemma.
Modern circuits feature billion of transistors, and neither power management
techniques nor batteries capacity are able to endure the increasingly higher
integration capability of digital devices. Besides, power concerns come together
with modern nanoscale silicon technology design issues.
On one hand, system failure rates are expected to increase exponentially at
every technology node when integrated circuit wear-out failure mechanisms
are not compensated for. However, error detection and/or correction mechanisms
have a non-negligible impact on the network power.
On the other hand, to meet the stringent time-to-market deadlines, the design
cycle of such a distributed and heterogeneous architecture must not be
prolonged by unnecessary design iterations.
Overall, there is a clear need to better discriminate reliability strategies and
interconnect topology solutions upfront, by ranking designs based on power
metric. In this thesis, we tackle this challenge by proposing power-aware
design technologies.
Finally, we take into account the most aggressive and disruptive methodology
for embedded systems with ultra-low power constraints, by migrating
NoC basic building blocks to asynchronous (or clockless) design style. We
deal with this challenge delivering a standard cell design methodology and
mainstream CAD tool
ows, in this way partially relaxing the requirement
of using asynchronous blocks only as hard macros
Driving the Network-on-Chip Revolution to Remove the Interconnect Bottleneck in Nanoscale Multi-Processor Systems-on-Chip
The sustained demand for faster, more powerful chips has been met by the
availability of chip manufacturing processes allowing for the integration of increasing
numbers of computation units onto a single die. The resulting outcome,
especially in the embedded domain, has often been called SYSTEM-ON-CHIP
(SoC) or MULTI-PROCESSOR SYSTEM-ON-CHIP (MP-SoC).
MPSoC design brings to the foreground a large number of challenges, one of
the most prominent of which is the design of the chip interconnection. With a
number of on-chip blocks presently ranging in the tens, and quickly approaching
the hundreds, the novel issue of how to best provide on-chip communication
resources is clearly felt.
NETWORKS-ON-CHIPS (NoCs) are the most comprehensive and scalable
answer to this design concern. By bringing large-scale networking concepts to
the on-chip domain, they guarantee a structured answer to present and future
communication requirements. The point-to-point connection and packet switching
paradigms they involve are also of great help in minimizing wiring overhead
and physical routing issues. However, as with any technology of recent inception,
NoC design is still an evolving discipline. Several main areas of interest
require deep investigation for NoCs to become viable solutions:
• The design of the NoC architecture needs to strike the best tradeoff among
performance, features and the tight area and power constraints of the onchip
domain.
• Simulation and verification infrastructure must be put in place to explore,
validate and optimize the NoC performance.
• NoCs offer a huge design space, thanks to their extreme customizability in
terms of topology and architectural parameters. Design tools are needed
to prune this space and pick the best solutions.
• Even more so given their global, distributed nature, it is essential to evaluate
the physical implementation of NoCs to evaluate their suitability for
next-generation designs and their area and power costs.
This dissertation performs a design space exploration of network-on-chip architectures,
in order to point-out the trade-offs associated with the design of
each individual network building blocks and with the design of network topology
overall. The design space exploration is preceded by a comparative analysis
of state-of-the-art interconnect fabrics with themselves and with early networkon-
chip prototypes. The ultimate objective is to point out the key advantages
that NoC realizations provide with respect to state-of-the-art communication
infrastructures and to point out the challenges that lie ahead in order to make
this new interconnect technology come true. Among these latter, technologyrelated
challenges are emerging that call for dedicated design techniques at all
levels of the design hierarchy. In particular, leakage power dissipation, containment
of process variations and of their effects. The achievement of the above
objectives was enabled by means of a NoC simulation environment for cycleaccurate
modelling and simulation and by means of a back-end facility for the
study of NoC physical implementation effects. Overall, all the results provided
by this work have been validated on actual silicon layout