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Title: Obladi: Oblivious Serializable Transactions in the Cloud
This paper presents the design and implementation of Obladi, the first system to provide ACID transactions while also hiding access patterns. Obladi uses as its building block oblivious RAM, but turns the demands of supporting transac- tions into a performance opportunity. By executing transac- tions within epochs and delaying commit decisions until an epoch ends, Obladi reduces the amortized bandwidth costs of oblivious storage and increases overall system through- put. These performance gains, combined with new oblivious mechanisms for concurrency control and recovery, allow Obladi to execute OLTP workloads with reasonable through- put: it comes within 5× to 12× of a non-oblivious baseline on the TPC-C, SmallBank, and FreeHealth applications. Latency overheads, however, are higher (70× on TPC-C).
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Proceedings of the 13th USENIX Symposium on Operating Systems Design and Implementation (OSDI ’18)
Sponsoring Org:
National Science Foundation
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