37,256 research outputs found
On the computational power of self-stabilizing systems
AbstractThe computational power of self-stabilizing distributed systems is examined. Assuming availability of any number of processors, each with (small) constant size memory we show that any computable problem can be realized in a self-stabilizing fashion.The result is derived by presenting a distributed system which tolerates transient faults and simulates the execution of a Turing machine. The total amount of memory required by the distributed system is equal to the memory used by the Turing machine (up to a constant factor)
Minimizing Message Size in Stochastic Communication Patterns: Fast Self-Stabilizing Protocols with 3 bits
This paper considers the basic model of communication, in
which in each round, each agent extracts information from few randomly chosen
agents. We seek to identify the smallest amount of information revealed in each
interaction (message size) that nevertheless allows for efficient and robust
computations of fundamental information dissemination tasks. We focus on the
Majority Bit Dissemination problem that considers a population of agents,
with a designated subset of source agents. Each source agent holds an input bit
and each agent holds an output bit. The goal is to let all agents converge
their output bits on the most frequent input bit of the sources (the majority
bit). Note that the particular case of a single source agent corresponds to the
classical problem of Broadcast. We concentrate on the severe fault-tolerant
context of self-stabilization, in which a correct configuration must be reached
eventually, despite all agents starting the execution with arbitrary initial
states.
We first design a general compiler which can essentially transform any
self-stabilizing algorithm with a certain property that uses -bits
messages to one that uses only -bits messages, while paying only a
small penalty in the running time. By applying this compiler recursively we
then obtain a self-stabilizing Clock Synchronization protocol, in which agents
synchronize their clocks modulo some given integer , within rounds w.h.p., and using messages that contain bits only.
We then employ the new Clock Synchronization tool to obtain a
self-stabilizing Majority Bit Dissemination protocol which converges in time, w.h.p., on every initial configuration, provided that the
ratio of sources supporting the minority opinion is bounded away from half.
Moreover, this protocol also uses only 3 bits per interaction.Comment: 28 pages, 4 figure
Evaluating Asymmetric Multicore Systems-on-Chip using Iso-Metrics
The end of Dennard scaling has pushed power consumption into a first order
concern for current systems, on par with performance. As a result,
near-threshold voltage computing (NTVC) has been proposed as a potential means
to tackle the limited cooling capacity of CMOS technology. Hardware operating
in NTV consumes significantly less power, at the cost of lower frequency, and
thus reduced performance, as well as increased error rates. In this paper, we
investigate if a low-power systems-on-chip, consisting of ARM's asymmetric
big.LITTLE technology, can be an alternative to conventional high performance
multicore processors in terms of power/energy in an unreliable scenario. For
our study, we use the Conjugate Gradient solver, an algorithm representative of
the computations performed by a large range of scientific and engineering
codes.Comment: Presented at HiPEAC EEHCO '15, 6 page
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