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Publications associées (28)
Efficient Concurrent Analytical Query Processing using Data and Workload-conscious Sharing
Analytical workloads are evolving as the number of users surges and applications that submit queries in batches become popular. However, traditional analytical databases that optimize-then-execute each query individually struggle to provide timely response ...
EPFL2023Micro-architectural Analysis of Database Workloads
Database workloads have significantly evolved in the past twenty years. Traditional database systems that are mainly used to serve Online Transactional Processing (OLTP) workloads evolved into specialized database systems that are optimized for particular ...
EPFL2021Bridging the Latency Gap between NVM and DRAM for Latency-bound Operations
Anastasia Ailamaki, Georgios Psaropoulos
Non-Volatile Memory (NVM) technologies exhibit 4× the read access latency of conventional DRAM. When the working set does not fit in the processor cache, this latency gap between DRAM and NVM leads to more than 2× runtime increase for queries dominated by ...
ACM2019Multimodal person recognition in audio-visual streams
Multimedia databases are growing rapidly in size in the digital age. To increase the value of these data and to enhance the user experience, there is a need to make these videos searchable through automatic indexing. Because people appearing and talking in ...
EPFL2019Improving Main-memory Database System Performance through Cooperative Multitasking
Database systems access memory either sequentially or randomly. Contrary to sequential access and despite the extensive efforts of
computer architects, compiler writers, and system builders, random access to data larger than the processor cache has been s ...
EPFL2019Time- and Space-Efficient Spatial Data Analytics
Advances in data acquisition technologies and supercomputing for large-scale simulations have led to an exponential growth in the volume of spatial data. This growth is accompanied by an increase in data complexity, such as spatial density, but also by mor ...
EPFL2019HD-Index: Pushing the Scalability-Accuracy Boundary for Approximate kNN Search in High-Dimensional Spaces
Akhil Arora, Arnab Bhattacharya, Piyush Kumar
Nearest neighbor searching of large databases in high-dimensional spaces is inherently difficult due to the curse of dimensionality. A flavor of approximation is, therefore, necessary to practically solve the problem of nearest neighbor search. In this pap ...
ASSOC COMPUTING MACHINERY2018Practical Private Range Search in Depth
Odysseas Papapetrou, Ioannis Demertzis
We consider a data owner that outsources its dataset to an untrusted server. The owner wishes to enable the server to answer range queries on a single attribute, without compromising the privacy of the data and the queries. There are several schemes on “pr ...
2018Interleaving with Coroutines: A Practical Approach for Robust Index Joins
Anastasia Ailamaki, Georgios Psaropoulos
Index join performance is determined by the efficiency of the lookup operation on the involved index. Although database indexes are highly optimized to leverage processor caches, main memory accesses inevitably increase lookup runtime when the index outsiz ...
VLDB Endowment Inc.2017BLOCK: Efficient Execution of Spatial Range Queries in Main-Memory
Anastasia Ailamaki, Thomas Heinis, Farhan Tauheed, Matthaios Alexandros Olma
The execution of spatial range queries is at the core of many applications, particularly in the simulation sciences but also in many other domains. Although main memory in desktop and supercomputers alike has grown considerably in recent years, most spatia ...
ACM New York, NY, USA2017