Francisco José Santos de Carvalho


Shared Logs With Support for Multi-Consistency


Tese submetida para provas de mestrado em Engenharia Informática e de Computadores Instituto Superior Técnico, Universidade de Lisboa.

Abstract

Shared logs are a key component of modern distributed systems. Typically, logs record a totally ordered sequence of events and/or commands that need to be (or have been) executed in a distributed system. Processing events in the total order defined by the log simplifies the task of providing strong consistency guarantees to the application, such as linearizability or serializability. Unfortunately, processing record entries in serial order is also a source of bottlenecks and high latency, in particular when the system experiences delays in filling some records. One way to circumvent these limitations is by exploring application semantics, for instance by allowing operations that are known to be commutative to be processed in parallel and by allowing some entries to be processed even if some of the previous entries have not been filled. In this dissertation we show how hybrid consistency models can be added to shared logs, namely, we present the design and evaluation of RB-Log, a shared log with support for Red-Blue consistency with Immediate operations. An experimental evaluation shows that RB-Log can reduce the latency of blue operations as long as red operations do not exceed 50% of the workload.

Publicações

Shared Logs With Support for Multi-Consistency
Francisco José Santos de Carvalho
MSc Thesis. Instituto Superior Técnico, Universidade de Lisboa.
October 2025.
Available BibTeX, MSC Thesis, and extended abstract, and mid-term report.
Suporte para Multi-Coerência em Históricos Partilhados
F. Carvalho, R. Soares, and L. Rodrigues.
Décimo sexto Simpósio de Informática (Inforum), Évora, Portugal, Sep. 2025.
(accepted as "poster'')
Available BibTeX, poster (pdf).

Luís Rodrigues