ConferenceProceedings of the ACM SIGMOD International Conference on Management of Data · June 14, 2020
There is a lot of interest today in building autonomous (or, self-driving) data processing systems. An emerging school of thought is to leverage AI-driven "black box" algorithms for this purpose. In this paper, we present a contrarian view. We study the pr ...
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ConferenceProceedings of the ACM SIGMOD International Conference on Management of Data · June 25, 2019
Data Analytics Frameworks encourage sharing of clusters for execution of mixed workloads by promising fairness and isolation along with high performance and resource utilization. However, concurrent query executions on such shared clusters result in increa ...
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ConferenceProceedings of the ACM SIGMOD International Conference on Management of Data · June 25, 2019
More than 10,000 enterprises worldwide use the big data stack composed of multiple distributed systems. At Unravel, we build the next-generation APM platform for the big data stack, and we have worked with a representative sample of these enterprises that ...
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ConferenceProceedings. ACM-SIGMOD International Conference on Management of Data · June 2019
Resource interferences caused by concurrent queries is one of the key reasons for unpredictable performance and missed workload SLAs in cluster computing systems. Analyzing these inter-query resource interactions is critical in order to answer time-sensiti ...
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ConferenceCIDR 2019 - 9th Biennial Conference on Innovative Data Systems Research · January 1, 2019
More than 10,000 enterprises worldwide today use the big data stack that is composed of multiple distributed systems. At Unravel, we have worked with a representative sample of these enterprises that covers most industry verticals. This sample also covers ...
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ConferenceProceedings. ACM-SIGMOD International Conference on Management of Data · June 2018
Unpredictability in query runtimes can arise in a shared cluster as a result of resource contentions caused by inter-query interactions. iQCAR - inter Query Contention AnalyzeR is a system that formally models these inter ...
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ConferenceProceedings of the VLDB Endowment · January 1, 2018
Database and big data analytics systems such as Hadoop and Spark have a large number of configuration parameters that control memory distribution, I/O optimization, parallelism, and compression. Improper parameter settings can cause significant performance ...
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ConferenceProceedings of the VLDB Endowment · August 1, 2017
Allocation and usage of memory in modern data-processing platforms is based on an interplay of algorithms at multiple levels: (i) at the resource-management level across containers allocated by resource managers like Mesos and Yarn, (ii) at the container l ...
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ConferenceProceedings of the ACM SIGMOD International Conference on Management of Data · May 9, 2017
Systems for processing big data-e.g., Hadoop, Spark, and massively parallel databases-need to run workloads on behalf of multiple tenants simultaneously. The abundant disk-based storage in these systems is usually complemented by a smaller, but much faster ...
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Chapter · January 1, 2016
We describe Cümülön, a system aimed at helping users develop and deploy matrix-based data analysis programs in a public cloud. A key feature of Cümülön is its end-to-end support for the so-called spot instances-machines whose market price fluctuates over t ...
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ConferenceProceedings of the VLDB Endowment · January 1, 2016
Multi-tenant database systems have a component called the Resource Manager, or RM that is responsible for allocating resources to tenants. RMs today do not provide direct support for performance objectives such as: "Average job response time of tenant A mu ...
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Journal ArticleProceedings - International Conference on Data Engineering · January 1, 2014
The desire of companies to analyze web-site activity data quickly in order to show personalized content and advertisements to users has led to renewed interest in continuous query processing. One important query class here is windowed aggregation which doe ...
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Journal ArticleProceedings of the 3rd Workshop on Data Analytics in the Cloud, DanaC 2014 - In Conjunction with ACM SIGMOD/PODS Conference · January 1, 2014Cite
Journal ArticleProceedings of the VLDB Endowment · January 1, 2014
Following the 'no one size fits all' philosophy, active research in big data platforms is focusing on creating an environment for multiple 'one-size' systems to co-exist and cooperate in the same cluster. Consequently, it has now become imperative to provi ...
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ConferenceAdvances in Database Technology - EDBT 2014: 17th International Conference on Extending Database Technology, Proceedings · January 1, 2014
The MapReduce programming model has become widely adopted for large scale analytics on big data. MapReduce systems such as Hadoop have many tuning parameters, many of which have a significant impact on performance. The map and reduce functions that make up ...
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Journal ArticleProceedings - International Conference on Data Engineering · August 15, 2013
Parallel database systems and MapReduce systems (most notably Hadoop) are essential components of today's infrastructure for Big Data analytics. These systems process multiple concurrent workloads consisting of complex user requests, where each request is ...
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Journal ArticleProceedings of the ACM SIGMOD International Conference on Management of Data · July 29, 2013
It is our great pleasure to welcome you to the 2013 ACM SIGMOD Conference on Management of Data, SIGMOD'13. This year the conference is being held in New York City, at the Millennium Broadway Hotel in the Times Square theater district. New York City provid ...
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Journal ArticleProceedings of the ACM SIGMOD International Conference on Management of Data · July 29, 2013
As the data collected by enterprises grows in scale, there is a growing trend of performing data analytics on large datasets. Batch processing systems that can handle petabyte scale of data, such as Hadoop, have flourished and gained traction in the indust ...
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Journal ArticleProceedings of the ACM SIGMOD International Conference on Management of Data · July 29, 2013
We present Cumulon, a system designed to help users rapidly develop and intelligently deploy matrix-based big-data analysis programs in the cloud. Cumulon features a flexible execution model and new operators especially suited for such workloads. We show h ...
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ConferenceACM International Conference Proceeding Series · May 2, 2013
The need to perform testing and tuning of database instances with production-like workloads (W), configurations (C), data (D), and resources (R) arises routinely. The further W, C, D, and R used in testing and tuning deviate from what is observed on the pr ...
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ConferenceCIDR 2013 - 6th Biennial Conference on Innovative Data Systems Research · January 1, 2013
While “no one size fits all” is a sound philosophy for system designers to follow, it poses multiple challenges for application developers and system administrators. It can be hard for an application developer to pick one system when the needs of her appli ...
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Journal ArticleACM International Conference Proceeding Series · December 19, 2012
Solid-state drives are becoming a viable alternative to magnetic disks in database systems, but their performance characteristics, particularly those caused by their erase-before-write behavior, make conventional database indexes a poor fit. There have bee ...
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Journal ArticleFoundations and Trends in Databases · December 1, 2012
Timely and cost-effective analytics over "big data" has emerged as a key ingredient for success in many businesses, scientific and engineering disciplines, and government endeavors. Web clicks, social media, scientific experiments, and datacenter monitorin ...
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Journal ArticleProceedings of the VLDB Endowment · January 1, 2012
There is a growing trend of performing analysis on large datasets using workflows composed of MapReduce jobs connected through producer-consumer relationships based on data. This trend has spurred the development of a number of interfaces-ranging from prog ...
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Journal ArticleProceedings of the 2nd ACM Symposium on Cloud Computing, SOCC 2011 · November 30, 2011
Infrastructure-as-a-Service (IaaS) cloud platforms have brought two unprecedented changes to cluster provisioning practices. First, any (nonexpert) user can provision a cluster of any size on the cloud within minutes to run her data-processing jobs. The us ...
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Journal ArticleCIDR 2011 - 5th Biennial Conference on Innovative Data Systems Research, Conference Proceedings · October 11, 2011
Timely and cost-effective analytics over "Big Data" is now a key ingredient for success in many businesses, scientific and engineering disciplines, and government endeavors. The Hadoop software stack-which consists of an extensible MapReduce execution engi ...
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Journal ArticleProceedings of the VLDB Endowment · August 1, 2011
Occasional corruption of stored data is an unfortunate byproduct of the complexity of modern systems. Hardware errors, software bugs, and mistakes by human administrators can corrupt important sources of data. The dominant practice to deal with data corrup ...
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Journal ArticleProceedings of the VLDB Endowment · August 1, 2011
MapReduce has emerged as a viable competitor to database systems in big data analytics. MapReduce programs are being written for a wide variety of application domains including business data processing, text analysis, natural language processing, Web graph ...
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Journal ArticleVLDB Journal · August 1, 2011
The typical workload in a database system consists of a mix of multiple queries of different types that run concurrently. Interactions among the different queries in a query mix can have a significant impact on database performance. Hence, optimizing datab ...
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Journal ArticleProceedings - International Conference on Data Engineering · June 10, 2011
The danger of production or backup data becoming corrupted is a problem that database administrators dread. This position paper aims to bring this problem to the attention of the database research community, which, surprisingly, has by and large overlooked ...
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Journal ArticleProceedings of the VLDB Endowment · January 1, 2011
MapReduce has emerged as a viable competitor to database systems in big data analytics. MapReduce programs are being written for a wide variety of application domains including business data processing, text analysis, natural language processing, Web graph ...
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Journal ArticleProceedings of the ACM SIGMOD International Conference on Management of Data · January 1, 2011
Table partitioning splits a table into smaller parts that can be accessed, stored, and maintained independent of one another. From their traditional use in improving query performance, partitioning strategies have evolved into a powerful mechanism to impro ...
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Journal ArticleProceedings of the ACM SIGMOD International Conference on Management of Data · January 1, 2011
Occasional corruption of stored data is an unfortunate byproduct of the complexity of modern systems. Hardware errors, software bugs, and mistakes by human administrators can corrupt important sources of data. The dominant practice to deal with data corrup ...
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Journal ArticleACM International Conference Proceeding Series · January 1, 2011
A question that database administrators (DBAs) routinely need to answer is how long a batch query workload will take to complete. This question arises, for example, while planning the execution of different report-generation workloads to fit within availab ...
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Journal ArticleProceedings of the 1st ACM Symposium on Cloud Computing, SoCC '10 · July 30, 2010
Timely and cost-effective processing of large datasets has become a critical ingredient for the success of many academic, government, and industrial organizations. The combination of MapReduce frameworks and cloud computing is an attractive proposition for ...
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Journal ArticleProceedings of the ACM SIGMOD International Conference on Management of Data · July 23, 2010
iTuned is a tool that takes a SQL workload as input and recommends good settings for database configuration parameters such as buffer pool sizes, multi-programming level, and number of I/O daemons. iTuned also provides response-surface and sensitivity-anal ...
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Journal ArticleProceeding of the 7th International Conference on Autonomic Computing, ICAC '10 and Co-located Workshops · July 23, 2010
Elasticity - where systems acquire and release resources in response to dynamic workloads, while paying only for what they need - is a driving property of cloud computing. At the core of any elastic system is an automated controller. This paper addresses e ...
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Journal ArticleProceedings - International Conference on Data Engineering · June 1, 2010
While planning the execution of report-generation workloads, database administrators often need to know how long different query workloads will take to run. Database systems run mixes of multiple queries of different types concurrently. Hence, estimating t ...
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Journal ArticleProceedings of the VLDB Endowment · January 1, 2010
The need to improve a suboptimal execution plan picked by the query optimizer for a repeatedly run SQL query arises routinely. Complex expressions, skewed or correlated data, and changing conditions can cause the optimizer to make mistakes. For example, th ...
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Journal ArticleProceedings of the 1st Workshop on Automated Control for Datacenters and Clouds, ACDC '09 · November 30, 2009
With advances in virtualization technology, virtual machine services offered by cloud utility providers are becoming increasingly powerful, anchoring the ecosystem of cloud services. Virtual computing services are attractive in part because they enable cus ...
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Journal ArticleProceedings of the 2nd International Workshop on Testing Database Systems, DBTest '09 · November 23, 2009
SQL tuning - the attempt to improve a poorly-performing execution plan produced by the database query optimizer - is a critical aspect of database performance tuning. Ironically, as commercial databases strive to improve on the manageability front, SQL tun ...
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Journal ArticleProceedings of the 2nd International Workshop on Testing Database Systems, DBTest '09 · November 23, 2009
Database workloads consist of mixes of queries that run concurrently and interact with each other. In this paper, we demonstrate that query interactions can have a significant impact on database system performance. Hence, we argue that it is important to t ...
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ConferenceProceedings - International Conference on Data Engineering · July 8, 2009
Failures of Internet services and enterprise systems lead to user dissatisfaction and considerable loss of revenue. Since manual diagnosis is often laborious and slow, there is considerable interest in tools that can diagnose the cause of failures quickly ...
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ConferenceProceedings of the 7th USENIX Conference on File and Storage Technologies, FAST 2009 · January 1, 2009
We present DIADS, an integrated DIAgnosis tool for Databases and Storage area networks (SANs). Existing diagnosis tools in this domain have a database-only (e.g., [11]) or SAN-only (e.g., [28]) focus. DIADS is a first-of-a-kind framework based on a careful ...
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ConferenceWorkshop on Hot Topics in Cloud Computing, HotCloud 2009 · January 1, 2009
This paper addresses “reflective” control for applications that use server resources from a shared cloud infrastructure opportunistically. In this approach, an external reflective controller launches application functions based on knowledge of what resourc ...
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ConferenceProceedings of HotOS 2009 - 12th Workshop on Hot Topics in Operating Systems · January 1, 2009
In this position paper, we argue that an important piece of the system administration puzzle has largely been left untouched by researchers. This piece involves mechanisms and policies to identify as well as collect missing instrumentation data; the missin ...
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Journal ArticleProceedings of the VLDB Endowment · January 1, 2009
Many enterprise environments have databases running on network-attached storage infrastructure (referred toas Storage Area Networks or SANs). Both the database and the SAN are complex subsystems that are managed by separate teams of administrators. As ofte ...
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ConferenceSIGMOD-PODS'09 - Proceedings of the International Conference on Management of Data and 28th Symposium on Principles of Database Systems · January 1, 2009
The database community has made rapid strides in capturing, representing, and querying uncertain data. Probabilistic databases capture the inherent uncertainty in derived tuples as probability estimates. Data acquisition and stream systems can produce succ ...
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Journal ArticleProceedings of the VLDB Endowment · January 1, 2009
Database systems have a large number of configuration parameters that control memory distribution, I/O optimization, costing of query plans, parallelism, many aspects of logging, recovery, and other behavior. Regular users and even expert database administ ...
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ConferenceInternational Conference on Information and Knowledge Management, Proceedings · December 1, 2008
The typical workload in a database system consists of a mixture of multiple queries of different types, running concurrently and interacting with each other. Hence, optimizing performance requires reasoning about query mixes and their interactions, rather ...
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Journal Article2008 IEEE International Symposium on Modeling, Analysis and Simulation of Computer and Telecommunication Systems, MASCOTS · December 1, 2008
Manually tuning tens to hundreds of configuration parameters in a complex software system like a database or an application server is an arduous task. Recent work has looked into automated approaches for recommending good configuration settings that adopti ...
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Journal ArticleProceedings - International Conference on Data Engineering · October 1, 2008
The typical workload in a database system consists of a mixture of multiple queries of different types, running concurrently and interacting with each other. Hence, optimizing performance requires reasoning about query mixes and their interactions, rather ...
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ConferenceProceedings - International Conference on Data Engineering · October 1, 2008
Many popular Web sites suffer occasional user-visible problems such as slow responses, blank pages or error messages being displayed, items not being added to shopping carts, database slowdowns, and others. Such deviations of systems from desired behavior, ...
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Journal Article5th International Conference on Autonomic Computing, ICAC 2008 · September 18, 2008
There is widespread interest today in developing tools that can diagnose the cause of a system failure accurately and efficiently based on monitoring data collected from the system. Over time, the system monitoring data will contain two types of failure da ...
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ConferenceProceedings of the 2008 USENIX Annual Technical Conference, USENIX 2008 · January 1, 2008
A common approach to benchmarking a server is to measure its behavior under load from a workload generator. Often a set of such experiments is required—perhaps with different server configurations or workload parameters—to obtain a statistically sound resu ...
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Conference3rd Workshop on Tackling Computer Systems Problems with Machine Learning Techniques, SysML 2008 · January 1, 2008
Automated techniques to diagnose the cause of system failures based on monitoring data is an active area of research at the intersection of systems and machine learning. In this paper, we identify three tasks that form key building blocks in automated diag ...
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Journal ArticleProceedings - International Conference on Data Engineering · December 1, 2007
Are self-healing database-centric multitier services utopia or just a hard puzzle? We argue for the latter and aim to identify the missing pieces of this puzzle. We advocate robust and scalable learning-based approaches to self-healing that we expect to wo ...
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Journal ArticleProceedings of the ACM SIGMOD International Conference on Management of Data · October 30, 2007
Suppose a long-running analytical query is executing on a database server and has been allocated a large amount of physical memory. A high-priority task comes in and we need to run it immediately with all available resources. We have several choices. We co ...
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Journal ArticleProceedings of the ACM SIGMOD International Conference on Management of Data · October 30, 2007
Utility computing delivers compute and storage resources to applications as an 'on-demand utility', much like electricity, from a distributed collection of computing resources. There is great interest in running database applications on utility resources ( ...
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ConferenceProceedings of the 2nd International Workshop on Hot Topics in Autonomic Computing, HotAC 2007, Held in conjunction with ICAC 2007 · January 1, 2007
This paper introduces Automat, a testbed architecture and prototype for research in autonomic services and hosting centers. Automat is an interactive web-based laboratory in which users allocate resources from an ondemand server cluster to experiment with ...
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Conference33rd International Conference on Very Large Data Bases, VLDB 2007 - Conference Proceedings · January 1, 2007
Forecasting future events based on historic data is useful in many domains like system management, adaptive query processing, environmental monitoring, and financial planning. We describe the Fa system where users and applications can pose declarative fore ...
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Journal ArticleProceedings of the ACM SIGMOD International Conference on Management of Data · December 1, 2006
We propose to demonstrate Fa, an automated tool for timely and accurate prediction of Service-Level-Agreement (SLA) violations caused by performance problems in database systems. Fa periodically collects performance data at three levels: applications, data ...
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Journal ArticleProceedings - 3rd International Conference on Autonomic Computing, ICAC 2006 · December 1, 2006
Shared computing utilities allocate compute, network, and storage resources to competing applications on demand. An awareness of the demands and behaviors of the hosted applications can help the system to manage its resources more effectively. This paper p ...
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Journal ArticleVLDB Journal · June 1, 2006
CQL, a continuous query language, is supported by the STREAM prototype data stream management system (DSMS) at Stanford. CQL is an expressive SQL-based declarative language for registering continuous queries against streams and stored relations. We begin b ...
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ConferenceVLDB 2006 - Proceedings of the 32nd International Conference on Very Large Data Bases · January 1, 2006
We present the NIMO system that automatically learns cost models for predicting the execution time of computational-science applications running on large-scale networked utilities such as computational grids. Accurate cost models are important for selectin ...
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Journal ArticleProceedings - International Conference on Data Engineering · December 12, 2005
We address the problem of executing continuous multiway join queries in unpredictable and volatile environments. Our query class captures windowed join queries in data stream systems as well as conventional maintenance of materialized join views. Our adapt ...
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Journal ArticleLecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) · December 1, 2005
A classical problem in query optimization is to find the optimal ordering of a set of possibly correlated selections. We provide an abstraction of this problem as a generalization of set cover called pipelined set cover, where the sets are applied sequenti ...
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Journal ArticleVLDB 2005 - Proceedings of 31st International Conference on Very Large Data Bases · December 1, 2005
Query optimizers in current database systems are designed to pick a single efficient plan for a given query based on current statistical properties of the data. However, different subsets of the data can sometimes have very different statistical properties ...
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Journal Article2nd Biennial Conference on Innovative Data Systems Research, CIDR 2005 · December 1, 2005
A great deal of work on adaptive query processing has been done over the last few years: Adaptive query processing has been used to detect and correct optimizer errors due to incorrect statistics or simplified cost metrics; it has been applied to long-runn ...
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Journal ArticleProceedings of the ACM SIGMOD International Conference on Management of Data · December 1, 2005
Traditional query optimizers rely' on the accuracy of estimated statistics of intermediate subexpressions to choose good query execution plans, This design often leads to suboptiinal plan choices for complex queries since errors in estimates grow exponenti ...
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Journal ArticleProceedings of the ACM SIGMOD International Conference on Management of Data · December 1, 2005
Traditional query optimizers rely on the accuracy of estimated statistics to choose good execution plans. This design often leads to suboptimal plan choices for complex queries, since errors in estimates for intermediate subexpressions grow exponentially i ...
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Journal ArticleVLDB Journal · December 1, 2004
In many applications involving continuous data streams, data arrival is bursty and data rate fluctuates over time. Systems that seek to give rapid or real-time query responses in such an environment must be prepared to deal gracefully with bursts in data a ...
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Journal ArticleACM Transactions on Database Systems · September 1, 2004
Continuous queries often require significant run-time state over arbitrary data streams. However, streams may exhibit certain data or arrival patterns, or constraints, that can be detected and exploited to reduce state considerably without compromising cor ...
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Journal ArticleProceedings of the ACM SIGMOD International Conference on Management of Data · July 27, 2004
StreaMon is the adaptive query processing engine of the STREAM prototype Data Stream Management System (DSMS). A fundamental challenge in many DSMS applications (e.g., network monitoring, financial monitoring over stock tickers, sensor processing) is that ...
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Journal ArticleACM Transactions on Database Systems · March 1, 2004
This article deals with continuous conjunctive queries with arithmetic comparisons and optional aggregation over multiple data streams. An algorithm is presented for determining whether or not any given query can be evaluated using a bounded amount of memo ...
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Journal ArticleLecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) · January 1, 2004
Despite the recent surge of research in query processing over data streams, little attention has been devoted to defining precise semantics for continuous queries over streams. We first present an abstract semantics based on several building blocks: formal ...
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Journal ArticleProceedings of the ACM SIGMOD International Conference on Management of Data · January 1, 2004
We consider the problem of pipelined filters, where a continuous stream of tuples is processed by a set of commutative filters. Pipelined filters are common in stream applications and capture a large class of multiway stream joins. We focus on the problem ...
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Journal ArticleProceedings of the ACM SIGMOD International Conference on Management of Data · December 1, 2003
In many applications involving continuous data streams, data arrival is bursty and data rate fluctuates over time. Systems that seek to give rapid or real-time query responses in such an environment must be prepared to deal gracefully with bursts in data a ...
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Journal ArticleProceedings of the ACM SIGACT-SIGMOD-SIGART Symposium on Principles of Database Systems · January 1, 2002
In this overview paper we motivate the need for and research issues arising from a new model of data processing. In this model, data does not take the form of persistent relations, but rather arrives in multiple, continuous, rapid, time-varying data stream ...
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Journal ArticleProceedings of the ACM SIGACT-SIGMOD-SIGART Symposium on Principles of Database Systems · January 1, 2002
We consider conjunctive queries with arithmetic comparisons over multiple continuous data streams. We specify an algorithm for determining whether or not a query can be evaluated using a bounded amount of memory for all possible instances of the data strea ...
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Journal ArticleProceedings of the ACM SIGMOD International Conference on Management of Data · September 29, 2001
While a variety of lossy compression schemes have been developed for certain forms of digital data (e.g., images, audio, video), the area of lossy compression techniques for arbitrary data tables has been left relatively un-explored. Nevertheless, such tec ...
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Journal ArticleComputer Communications · April 1, 2001
In this paper, we consider the problem of developing a MAC layer protocol to support real-time as well as non-real-time packet streams in Broadcast and Select WDM optical networks having rapidly tunable transmitters. We propose a MAC layer protocol which i ...
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Journal ArticleSIGMOD Record (ACM Special Interest Group on Management of Data) · January 1, 2001
In many recent applications, data may take the form of continuous data streams, rather than finite stored data sets. Several aspects of data management need to be reconsidered in the presence of data streams, offering a new research direction for the datab ...
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Journal ArticleSIGMOD Record (ACM Special Interest Group on Management of Data) · January 1, 2001
While a variety of lossy compression schemes have been developed for certain forms of digital data (e.g., images, audio, video), the area of lossy compression techniques for arbitrary data tables has been left relatively unexplored. Nevertheless, such tech ...
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