Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Towards Zero-Overhead Adaptive Indexing in Hadoop   Several research works have focused on supporting index access in MapReduce
systems. These works have allowed users to significantly speed up selective
MapReduce jobs by orders of magnitude. However, all these proposals require
users to create indexes upfront, which might be a difficult task in certain
applications (such as in scientific and social applications) where workloads
are evolving or hard to predict. To overcome this problem, we propose LIAH
(Lazy Indexing and Adaptivity in Hadoop), a parallel, adaptive approach for
indexing at minimal costs for MapReduce systems. The main idea of LIAH is to
automatically and incrementally adapt to users' workloads by creating clustered
indexes on HDFS data blocks as a byproduct of executing MapReduce jobs. Besides
distributing indexing efforts over multiple computing nodes, LIAH also
parallelises indexing with both map tasks computation and disk I/O. All this
without any additional data copy in main memory and with minimal
synchronisation. The beauty of LIAH is that it piggybacks index creation on map
tasks, which read relevant data from disk to main memory anyways. Hence, LIAH
does not introduce any additional read I/O-costs and exploit free CPU cycles.
As a result and in contrast to existing adaptive indexing works, LIAH has a
very low (or invisible) indexing overhead, usually for the very first job.
Still, LIAH can quickly converge to a complete index, i.e. all HDFS data blocks
are indexed. Especially, LIAH can trade early job runtime improvements with
fast complete index convergence. We compare LIAH with HAIL, a state-of-the-art
indexing technique, as well as with standard Hadoop with respect to indexing
overhead and workload performance.

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The categories of this paper are: hep-ex
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The categories of this paper are: dg-ga
3
The categories of this paper are: physics
26
The categories of this paper are: bayes-an
33
The categories of this paper are: plasm-ph
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The categories of this paper are: eess
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The categories of this paper are: mtrl-th
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The categories of this paper are: funct-an
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The categories of this paper are: acc-phys
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The categories of this paper are: q-alg
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The categories of this paper are: solv-int
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The categories of this paper are: nlin
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The categories of this paper are: hep-th
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The categories of this paper are: chem-ph
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The categories of this paper are: ao-sci
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The categories of this paper are: math-ph