The lock-free k-LSM relaxed priority queue
Paper in proceedings, 2015

We present a new, concurrent, lock-free priority queue that relaxes the delete-min operation to allow deletion of any of the ρ+1 smallest keys instead of only a minimal one, where ρ is a parameter that can be configured at runtime. It is built from a logarithmic number of sorted arrays, similar to log-structured merge-trees (LSM). For keys added and removed by the same thread the behavior is identical to a non-relaxed priority queue. We compare to state-of-the-art lock-free priority queues with both relaxed and non-relaxed semantics, showing high performance and good scalability of our approach.


Shared memory

Task-parallel programming

Concurrent data structure relaxation


M. Wimmer

Vienna University of Technology

J. Gruber

Vienna University of Technology

J.L. Träff

Vienna University of Technology

Philippas Tsigas

Chalmers, Computer Science and Engineering (Chalmers), Networks and Systems (Chalmers)

SIGPLAN Notices (ACM Special Interest Group on Programming Languages)

0362-1340 (ISSN)

Vol. 50 8 277-278





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