Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Using Weaker Consistency Models with Monitoring and Recovery for
  Improving Performance of Key-Value Stores   Consistency properties provided by most key-value stores can be classified
into sequential consistency and eventual consistency. The former is easier to
program with but suffers from lower performance whereas the latter suffers from
potential anomalies while providing higher performance. We focus on the problem
of what a designer should do if he/she has an algorithm that works correctly
with sequential consistency but is faced with an underlying key-value store
that provides a weaker consistency. We propose a detect-rollback based
approach: The designer identifies a correctness predicate, say $P$, and
continues to run the protocol, as our system monitors $P$. If $P$ is violated
(because of weaker consistency), the system rolls back and resumes the
computation at a state where $P$ holds.
  We evaluate this approach with graph-based applications running on the
Voldemort key-value store. Our experiments with deployment on Amazon AWS EC2
instances shows that using eventual consistency with monitoring can provide a
$50\%$ -- $80\%$ increase in throughput when compared with sequential
consistency. We also observe that the overhead of the monitoring itself was low
(typically less than $4\%$) and the latency of detecting violations was small.
In particular, in a scenario designed to intentionally cause a large number of
violations, more than $99.9\%$ of violations were detected in less than 50
milliseconds in regional networks, and in less than 3 seconds in global
networks.
  We find that for some applications, frequent rollback can cause the program
using eventual consistency to effectively \textit{stall}. We propose alternate
mechanisms for dealing with re-occurring rollbacks. Overall, for applications
considered in this paper, we find that even with rollback, eventual consistency
provides better performance than using sequential consistency.

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The categories of this paper are: acc-phys
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The categories of this paper are: dg-ga
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The categories of this paper are: nlin
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The categories of this paper are: nucl-ex
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The categories of this paper are: cond-mat
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The categories of this paper are: hep-lat
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The categories of this paper are: q-alg
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The categories of this paper are: math
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The categories of this paper are: adap-org
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The categories of this paper are: patt-sol
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The categories of this paper are: atom-ph
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The categories of this paper are: econ
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The categories of this paper are: solv-int
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The categories of this paper are: chem-ph
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The categories of this paper are: nucl-th
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The categories of this paper are: q-bio