Time+Place: Monday 02/06/2014 14:30 Room 337-8 Taub Bld.
Title: A principled approach to the performance-vs.-programmability trade-off in large-scale distributed data stores
Speaker: Marc Shapiro - Colloquium Lecture - NOTE UNUSUAL DAY http://pagesperso-systeme.lip6.fr/Marc.Shapiro/
Affiliation: INRIA & UMPC-LIP6
Host: Avi Mendelson


Distributed systems face a fundamental trade-off of consistency vs.
availability and performance.  Strong consistency is easy to understand 
but is slow, expensive, and is unavailable when the system partitions.  
Eventual consistency (EC) can be cheaper, faster, and more scalable, but 
is hard to understand and get correct.  We explore the spectrum gradations 
between those two endpoints from the perspective of parallelism, availability 
and responsiveness on the one hand, and the ease of programming and 
maintaining invariants on the other. 

When parallel updates to shared data are allowed, ensuring convergence 
is complex and often ad-hoc.  To convergence while avoiding rollback and
consensus, we propose a simple, scalable, but somewhat restrictive
programming model, Conflict-Free Replicated Data Types (CRDTs). Some simple
sufficient conditions ensure that all replicas of a CRDT object converge 
to a correct state, without requiring synchronisation or rollback.  CRDTs 
are safe by construction, and remain responsive, available and scalable 
despite high network latency, faults, or disconnection.

Joint work with Marek Zawirski, Masoud Saeida-Ardekani, and Nuno 

Short Bio: 
Marc Shapiro is a researcher in distributed and concurrent systems
at INRIA in Paris (France).  His research topics include large-scale
distributed computing systems, focusing on data replication and
consistency, especially in the wide area and in disconnected operation.

After his PhD at LAAS (Toulouse), Marc Shapiro did his research at MIT
(Cambridge, USA), CMIRH (Paris, France), INRIA (Rocquencourt, France),
Cornell University (Ithaca, USA), Sun Microsystems (Chelmsford, USA),
and Microsoft Research (Cambridge, UK).  He is currently a senior
researcher for INRIA in the Regal group (INRIA-LIP6).

Desserts will be served from 14:15
Lecture starts at 14:30