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Online Aggregation over Trees

C. Greg Plaxton, Mitul Tiwari, Praveen Yalagandula
2007 2007 IEEE International Parallel and Distributed Processing Symposium  
Consider a distributed network with nodes arranged in a tree, and each node having a local value.  ...  Our online lease-based aggregation algorithm is presented in the form of a fully distributed protocol, and the aforementioned consistency and performance results are formally established with respect to  ...  The global aggregate value is defined as the aggregate value over the set of all the nodes in the tree T .  ... 
doi:10.1109/ipdps.2007.370280 dblp:conf/ipps/PlaxtonTY07 fatcat:mcb6hjgotfcqpclqpcsvvhoxji


Robert Christensen, Lu Wang, Feifei Li, Ke Yi, Jun Tang, Natalee Villa
2015 Proceedings of the 2015 ACM SIGMOD International Conference on Management of Data - SIGMOD '15  
Online spatio-temporal aggregation and analytics are then derived based on the online samples, where approximate answers with approximation quality guarantees can be provided immediately from the start  ...  The quality of these online approximations improve over time. This demonstration proposal describes key ideas in the design of the STORM system, and presents the demonstration plan.  ...  Online aggregation and analytics enables interactive analytics and exploration over large scale spatio-temporal data.  ... 
doi:10.1145/2723372.2735373 dblp:conf/sigmod/ChristensenWLYT15 fatcat:raexlwd3ovcidkx4qi7hte37ba

Control Message Aggregation in Group Communication Protocols [chapter]

Sanjeev Khanna, Joseph Seffi Naor, Dan Raz
2002 Lecture Notes in Computer Science  
We define the multicast aggregation problem and design efficient online algorithms for it, both centralized and distributed.  ...  Since sending of control messages involves communication overhead, many protocols rely on aggregating a number of control messages and sending them together as a single packet over the network.  ...  The lemma now follows by summing over all sets of late packets in the trees {T 1 , ..., T τ }.  ... 
doi:10.1007/3-540-45465-9_13 fatcat:w2d3jg3kljdexje2yin4eoucz4

Answering ad hoc aggregate queries from data streams using prefix aggregate trees

Moonjung Cho, Jian Pei, Ke Wang
2006 Knowledge and Information Systems  
In this paper, we develop a novel prefix aggregate tree (PAT) structure for online warehousing data streams and answering ad hoc aggregate queries.  ...  In some business applications such as trading management in financial institutions, it is required to accurately answer ad hoc aggregate queries over data streams.  ...  Recently, several important applications see the strong demands of online answering ad hoc aggregate queries over fast data streams.  ... 
doi:10.1007/s10115-006-0024-8 fatcat:em44c34l3nhk7eunit2dp2addi

Spatial online sampling and aggregation

Lu Wang, Robert Christensen, Feifei Li, Ke Yi
2015 Proceedings of the VLDB Endowment  
With more and more samples, various spatial analytics and aggregations can be performed in an online, interactive fashion, with estimators that have better accuracy over time.  ...  The importance of spatial analytics and aggregation is everincreasing. An important challenge is to support interactive exploration over such data.  ...  More specifically, it finds the canonical cover for the input range query using a count tree over P (e.g, an aggregate R-tree).  ... 
doi:10.14778/2850583.2850584 fatcat:dydfmp6jafbuvkxrmk4ur57y6y

A comparative study of spanning tree and gossip protocols for aggregation

Lehel Nyers, Márk Jelasity
2015 Concurrency and Computation  
Our simulation study helps us identify the most important factors that differentiate between gossip and spanning tree aggregation: the time needed to compute a truly global output, the properties of the  ...  Distributed aggregation queries like average and sum can be implemented in different paradigms like gossip and hierarchical approaches.  ...  Figure 1 :Figure 2 : 12 Binary tree, no churn (left) and fast churn, 80% of the nodes online (right).  ... 
doi:10.1002/cpe.3549 fatcat:53czhrz4cra23fuckwazyoudee

O(depth)-Competitive Algorithm for Online Multi-level Aggregation [article]

Niv Buchbinder, Moran Feldman, Joseph Naor, Ohad Talmon
2017 arXiv   pre-print
In this problem requests arrive over time at the nodes of the tree, and each request specifies a deadline.  ...  We present an online O(D)-competitive algorithm for the problem, where D is the depth, or number of levels, of the aggregation tree.  ...  We study a very general online aggregation setting, considered recently by [7] , and known as the Online Multi-level Aggregation Problem with Deadlines.  ... 
arXiv:1701.01936v1 fatcat:cuv7q56k4jfpddyntowrysxhfq

AVCOL: Availability-aware information aggregation in large distributed systems under uncollaborative behavior

Ramsés Morales, Indranil Gupta
2009 Computer Networks  
trees, and auditing of nodes both during aggregation as well as in gossip-style (i.e., periodically).  ...  AVCOL uses several unique design decisions: per-aggregation tree construction where nodes are allowed a limited but flexible probabilistic choice of parents or children, probabilistic aggregation along  ...  For instance, in the Overnet system [4] the online node population size varies by a factor of 2 over a week and by a factor of 3 over a month.  ... 
doi:10.1016/j.comnet.2009.03.006 fatcat:qnkj7wmdqrfl7ls4eiia7x5npm

A Multilevel Indexing Method for Approximate Geospatial Aggregation Analysis

2018 IEICE transactions on information and systems  
In the first step, a parallel aR tree index is built to accelerate aggregate query locally.  ...  In terms of spatial online aggregation, traditional standalone serial methods gradually become limited.  ...  The first is the non indexed online approx- imate aggregation.  ... 
doi:10.1587/transinf.2018edl8120 fatcat:i6rwtmiu7ber3nok7rz5yelc2q

Distributed Algorithm for En Route Aggregation Decision in Wireless Sensor Networks

Hong Luo, Yonghe Liu, S.K. Das
2009 IEEE Transactions on Mobile Computing  
In this paper, focusing on optimizing over both transmission and aggregation costs, we develop an online algorithm capable of dynamically adjusting the route structure when sensor nodes join or leave the  ...  with static aggregation decision.  ...  MFST is a full aggregation tree proposed in [10] , which jointly optimizes over both the fusion and transmission costs and achieves 5 4 logðk þ 1Þ approximation ratio to the optimal solution.  ... 
doi:10.1109/tmc.2008.82 fatcat:6ig3fvwbsvatfmakqmgw3y7vfm

AMF: Aggregated Mondrian Forests for Online Learning [article]

Jaouad Mourtada and Stéphane Gaïffas and Erwan Scornet
2020 arXiv   pre-print
Using a variant of the Context Tree Weighting algorithm, we show that it is possible to efficiently perform an exact aggregation over all prunings of the trees; in particular, this enables to obtain a  ...  truly online parameter-free algorithm which is competitive with the optimal pruning of the Mondrian tree, and thus adaptive to the unknown regularity of the regression function.  ...  This aggregation step is performed in a purely online fashion, using an aggregation algorithm based on exponential weights, with a branching process prior over the subtrees.  ... 
arXiv:1906.10529v2 fatcat:t5u6x3ixkfeopj5hrrvzxctdgm

Parallel online aggregation in action

Chengjie Qin, Florin Rusu
2013 Proceedings of the 25th International Conference on Scientific and Statistical Database Management - SSDBM  
Online aggregation provides continuous estimates to the final result of a computation during the actual processing.  ...  Demonstration participants are shown how estimates to general SQL aggregation queries over terabytes of TPC-H data are generated during the entire processing.  ...  Partial Aggregation The first requirement in any online aggregation system is a mechanism to compute partial aggregates over some portion of the data.  ... 
doi:10.1145/2484838.2484874 dblp:conf/ssdbm/QinR13 fatcat:k6j55dowwbe2zmwnuwvwodkhfm

Spanning Tree or Gossip for Aggregation: A Comparative Study [chapter]

Lehel Nyers, Márk Jelasity
2014 Lecture Notes in Computer Science  
Our experiments help us identify the most important factors that differentiate between gossip and spanning tree aggregation: the time needed to compute a truly global output, the properties of the underlying  ...  In the literature, these two paradigms are routinely associated with stereotypes such as "trees are fragile and complicated" and "gossip is slow and expensive".  ...  Fig. 1 . 1 Binary tree, no churn (left) and fast churn, 80% of the nodes online (right).  ... 
doi:10.1007/978-3-319-09873-9_32 fatcat:wkugkile3zba7odx3zs44mezvm

Massively Parallel Anomaly Detection in Online Network Measurement

S. Shanbhag, T. Wolf
2008 2008 Proceedings of 17th International Conference on Computer Communications and Networks  
We propose (1) a novel aggregation process that uses continuous anomaly information (rather than binary outputs) from existing algorithms and (2) an anomaly tree representation to illustrate the state  ...  Index Terms-Network measurement, anomaly detection, data aggregation, network processor.  ...  Fig. 2 . 2 Normalization Function Fig. 3 . 3 1 , . . . , n Anomaly Tree Example. Dashed lines indicate nodes not shown to the user. Fig. 4 . 4 Behavior of Metrics Over Time.  ... 
doi:10.1109/icccn.2008.ecp.63 dblp:conf/icccn/ShanbhagW08 fatcat:hfadbw5hbrhi3dcot3egfgo5k4

Hold 'em or fold 'em?

Gautam Kumar, Ganesh Ananthanarayanan, Sylvia Ratnasamy, Ion Stoica
2016 Proceedings of the Eleventh European Conference on Computer Systems - EuroSys '16  
These systems parallelize computations over many processes and aggregate them hierarchically to get the final response (e.g., search engines and data analytics).  ...  Cedar's solution is theoretically sound, fully distributed, and generically applicable across systems that use aggregation trees since it is agnostic to the causes of performance variations.  ...  Figure 13 compares the percentage improvement in response quality over the baseline (proportional-split) for a two-level and a three-level aggregation tree.  ... 
doi:10.1145/2901318.2901351 dblp:conf/eurosys/KumarARS16 fatcat:vblamnyq5vgfjijbbm52cl2b3e
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