TY - GEN

T1 - Efficient transformations of obstruction-free algorithms into non-blocking algorithms

AU - Taubenfeld, Gadi

PY - 2007

Y1 - 2007

N2 - Three well studied progress conditions for implementing concurrent algorithms without locking are, obstruction-freedom, non-blocking and wait-freedom. Obstruction-freedom is weaker than non-blocking which, in turn, is weaker than wait-freedom. While obstruction-freedom and non-blocking have the potential to significantly improve the performance of concurrent applications, wait-freedom (although desirable) imposes too much overhead upon the implementation. In [5], Fich, Luchangco, Moir, and Shavit have presented an interesting transformation that converts any obstruction-free algorithm into a waitfree algorithm when analyzed in the unknown-bound semi-synchronous model. The FLMS transformation uses n atomic single-writer registers, n atomic multi-writer registers and a single fetch-and-increment object, where n is the number of processes. We define a time complexity measure for analyzing such transformations, and prove that the time complexity of the FLMS transformation is exponential in the number of processes n. This leads naturally to the question of whether the time and/or space complexity of the FLMS transformation can be improved by relaxing the wait-freedom progress condition. We present several efficient transformations that convert any obstruction-free algorithm into a non-blocking algorithm when analyzed in the unknown-bound semi-synchronous model. All our transformations have O(1) time complexity. One transformation uses n atomic singlewriter registers and a single compare-and-swap object; another transformation uses only a single compare-and-swap object which is assumed to support also a read operation.

AB - Three well studied progress conditions for implementing concurrent algorithms without locking are, obstruction-freedom, non-blocking and wait-freedom. Obstruction-freedom is weaker than non-blocking which, in turn, is weaker than wait-freedom. While obstruction-freedom and non-blocking have the potential to significantly improve the performance of concurrent applications, wait-freedom (although desirable) imposes too much overhead upon the implementation. In [5], Fich, Luchangco, Moir, and Shavit have presented an interesting transformation that converts any obstruction-free algorithm into a waitfree algorithm when analyzed in the unknown-bound semi-synchronous model. The FLMS transformation uses n atomic single-writer registers, n atomic multi-writer registers and a single fetch-and-increment object, where n is the number of processes. We define a time complexity measure for analyzing such transformations, and prove that the time complexity of the FLMS transformation is exponential in the number of processes n. This leads naturally to the question of whether the time and/or space complexity of the FLMS transformation can be improved by relaxing the wait-freedom progress condition. We present several efficient transformations that convert any obstruction-free algorithm into a non-blocking algorithm when analyzed in the unknown-bound semi-synchronous model. All our transformations have O(1) time complexity. One transformation uses n atomic singlewriter registers and a single compare-and-swap object; another transformation uses only a single compare-and-swap object which is assumed to support also a read operation.

UR - http://www.scopus.com/inward/record.url?scp=38049067169&partnerID=8YFLogxK

U2 - 10.1007/978-3-540-75142-7_34

DO - 10.1007/978-3-540-75142-7_34

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AN - SCOPUS:38049067169

SN - 9783540751410

T3 - Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)

SP - 450

EP - 464

BT - Distributed Computing - 21st International Symposium, DISC 2007, Proceedings

PB - Springer Verlag

T2 - 21st International Symposium on Distributed Computing, DISC 2007

Y2 - 24 September 2007 through 26 September 2007

ER -