Oblivious Tight Compaction In O(n) Time with Smaller Constant

Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 12238)


Oblivious compaction is a crucial building block for hash-based oblivious RAM. Asharov et al. recently gave a O(n) algorithm for oblivious tight compaction [2]. Their algorithm is deterministic and asymptotically optimal, but the implied constant is \({\gg }2^{111}\). We give a new algorithm for oblivious tight compaction that runs in time \({<}23913.17n + o(n)\). As part of our construction, we give a new result in the bootstrap percolation of random regular graphs.


Funding acknowledgements

This work was supported in part by DARPA and NIWC Pacific under contract N66001-15-C-4065, as well as the Office of the Director of National Intelligence (ODNI), Intelligence Advanced Research Projects Activity (IARPA), via 2019-1902070008. The views and conclusions contained herein are those of the authors and should not be interpreted as necessarily representing the official policies, either expressed or implied, of ODNI, IARPA, the Department of Defense, or the U.S. Government. The U.S. Government is authorized to reproduce and distribute reprints for governmental purposes notwithstanding any copyright annotation therein.

Rafail Ostrovsky was supported in part by NSF-BSF Grant 1619348, US-Israel BSF grant 2012366, DARPA under Cooperative Agreement No: HR0011-20-2-0025, Google Faculty Award, JP Morgan Faculty Award, IBM Faculty Research Award, Xerox Faculty Research Award, OKAWA Foundation Research Award, B. John Garrick Foundation Award, Teradata Research Award, and Lockheed-Martin Corporation Research Award.

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© Springer Nature Switzerland AG 2020

Authors and Affiliations

  1. 1.Stealth Software Technologies, Inc.Los AngelesUSA
  2. 2.Department of Computer Science and MathematicsUniversity of California, Los AngelesLos AngelesUSA

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