We introduce consistency-aware durability or CAD, a new approach to durability in distributed storage that enables strong
consistency while delivering high performance. We demonstrate the efficacy of this approach by designing cross-client
monotonic reads, a novel and strong consistency property
that provides monotonic reads across failures and sessions
in leader-based systems. We build ORCA, a modified version
of ZooKeeper that implements CAD and cross-client monotonic reads. We experimentally show that ORCA provides
strong consistency while closely matching the performance of
weakly consistent ZooKeeper. Compared to strongly consistent ZooKeeper, ORCA provides significantly higher throughput (1.8 – 3.3×), and notably reduces latency, sometimes by
an order of magnitude in geo-distributed settings.
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Strong and Efficient Consistency with Consistency-aware Durability
We introduce consistency-aware durability or Cad, a new approach to durability in distributed storage that enables strong consistency while delivering high performance. We demonstrate the efficacy of this approach by designing cross-client monotonic reads, a novel and strong consistency property that provides monotonic reads across failures and sessions in leader-based systems; such a property can be particularly beneficial in geo-distributed and edge-computing scenarios. We build Orca, a modified version of ZooKeeper that implements Cad and cross-client monotonic reads. We experimentally show that Orca provides strong consistency while closely matching the performance of weakly consistent ZooKeeper. Compared to strongly consistent ZooKeeper, Orca provides significantly higher throughput (1.8--3.3×) and notably reduces latency, sometimes by an order of magnitude in geo-distributed settings. We also implement Cad in Redis and show that the performance benefits are similar to that of Cad’s implementation in ZooKeeper.
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- Award ID(s):
- 1838733
- NSF-PAR ID:
- 10299723
- Date Published:
- Journal Name:
- ACM transactions on storage
- Volume:
- 17
- Issue:
- 1
- ISSN:
- 1553-3077
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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We introduce consistency-aware durability or CAD, a new approach to durability in distributed storage that enables strong consistency while delivering high performance. We demonstrate the efficacy of this approach by designing cross-client monotonic reads, a novel and strong consistency property that provides monotonic reads across failures and sessions in leader-based systems. We build ORCA, a modified version of ZooKeeper that implements CAD and cross-client mono- tonic reads. We experimentally show that ORCA provides strong consistency while closely matching the performance of weakly consistent ZooKeeper. Compared to strongly consistent ZooKeeper, ORCA provides significantly higher through- put (1.8 – 3.3x), and notably reduces latency, sometimes by an order of magnitude in geo-distributed settings.more » « less
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