Concurrency control algorithms | Concurrency control | Transaction processing

Optimistic concurrency control

Optimistic concurrency control (OCC), also known as optimistic locking, is a concurrency control method applied to transactional systems such as relational database management systems and software transactional memory. OCC assumes that multiple transactions can frequently complete without interfering with each other. While running, transactions use data resources without acquiring locks on those resources. Before committing, each transaction verifies that no other transaction has modified the data it has read. If the check reveals conflicting modifications, the committing transaction rolls back and can be restarted. Optimistic concurrency control was first proposed by H. T. Kung and John T. Robinson. OCC is generally used in environments with low data contention. When conflicts are rare, transactions can complete without the expense of managing locks and without having transactions wait for other transactions' locks to clear, leading to higher throughput than other concurrency control methods. However, if contention for data resources is frequent, the cost of repeatedly restarting transactions hurts performance significantly, in which case other concurrency control methods may be better suited. However, locking-based ("pessimistic") methods also can deliver poor performance because locking can drastically limit effective concurrency even when deadlocks are avoided. (Wikipedia).

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Fuzzy control of inverted pendulum

Fuzzy control of inverted pendulum, State-feedback controller is designed based on T-S fuzzy model with the consideration of system stability and performance.

From playlist Demonstrations

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Fuzzy control of inverted pendulum,

Fuzzy control of inverted pendulum, State-feedback controller is designed based on T-S fuzzy model with the consideration of system stability and performance. Details can be found in https://nms.kcl.ac.uk/hk.lam/HKLam/index.php/demonstrations

From playlist Demonstrations

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Melanie Zeilinger: "Learning-based Model Predictive Control - Towards Safe Learning in Control"

Intersections between Control, Learning and Optimization 2020 "Learning-based Model Predictive Control - Towards Safe Learning in Control" Melanie Zeilinger - ETH Zurich & University of Freiburg Abstract: The question of safety when integrating learning techniques in control systems has

From playlist Intersections between Control, Learning and Optimization 2020

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Everything You Need to Know About Control Theory

Control theory is a mathematical framework that gives us the tools to develop autonomous systems. Walk through all the different aspects of control theory that you need to know. Some of the concepts that are covered include: - The difference between open-loop and closed-loop control - How

From playlist Control Systems in Practice

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Yafeng Yin: "Rhythmic Traffic Management and Control in Fully Automated Vehicle Environment"

Mathematical Challenges and Opportunities for Autonomous Vehicles 2020 Workshop III: Large Scale Autonomy: Connectivity and Mobility Networks "Rhythmic Traffic Management and Control in Fully Automated Vehicle Environment" Yafeng Yin - University of Michigan Abstract: In this talk, we pr

From playlist Mathematical Challenges and Opportunities for Autonomous Vehicles 2020

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Lecture 14: Optimistic Concurrency Control

Lecture 14: Optimistic Concurrency Control MIT 6.824: Distributed Systems (Spring 2020) https://pdos.csail.mit.edu/6.824/

From playlist MIT 6.824 Distributed Systems (Spring 2020)

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Lecture 12: Distributed Transactions

Lecture 12: Distributed Transactions MIT 6.824: Distributed Systems (Spring 2020) https://pdos.csail.mit.edu/6.824/

From playlist MIT 6.824 Distributed Systems (Spring 2020)

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New Directions in Multiprocessor Synchronization

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From playlist Course | Computer Systems Laboratory Colloquium (2006-2007)

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Martin Odersky, "Working Hard to Keep It Simple" - OSCON Java 2011

Today's world of parallel and distributed computing poses hard new challenges for software development. A rapidly increasing number of developers now have to deal with races, deadlocks, non-determinism, and we are ill-equipped to do so. How can we keep things simple, in spite of the comple

From playlist OSCON 2011

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Is Software Development The Most Difficult Job ITW

Software development is difficult, why is that? If you are wondering “is software development right for me”, “is software development a good career”, or if a software development career is an easy one it probably depends on how you think about problems. You don’t need to be a genius to be

From playlist Teamwork and Leadership

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Constraint Enforcement for Improved Safety | Learning-Based Control, Part 2

Learn about the constraints of your system and how you can enforce those constraints so the system does not violate them. In safety-critical applications, constraint enforcement ensures that any control action taken does not result in the system exceeding a safety bound. Constraint enforce

From playlist Learning-Based Control

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Kurt Kremer: Multiscale modeling for soft matter - Perspectives and challenges

Abstract: Material properties of soft matter are governed by a delicate interplay of energetic and entropic contributions. In other words, generic universal aspects are as relevant as local chemistry specific properties. Thus many different time and length scales are intimately coupled, wh

From playlist Numerical Analysis and Scientific Computing

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What Is Robust Control? | Robust Control, Part 1

Watch the other videos in this series: Robust Control, Part 2: Understanding Disk Margin - https://youtu.be/XazdN6eZF80 Robust Control, Part 3: Disk Margins for MIMO Systems - https://youtu.be/sac_IYBjcq0 This videos covers a high-level introduction to robust control. The goal is to get

From playlist Robust Control

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UHCL 06a Graduate Database Course - Undergraduate Review Part 2

This video corresponds to the unit 1 notes for a graduate database (dbms) course taught by Dr. Gary D. Boetticher at the University of Houston - Clear Lake (UHCL). It provides an undergraduate review of databases. Please note that this video is split into two parts.

From playlist UHCL Graduate Database Course

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Rocky Mountain Ruby 2012 - Let's talk concurrency by Jose Valim

For a long time, the de facto way of doing multi-core concurrency was using threads. However, the complexity of manipulating threads and state affected negatively how developers perceive concurrency. Fortunately, languages like Clojure and Erlang implement new paradigms that aim to make co

From playlist Rocky Mountain Ruby 2012

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10 Adjoint state method

We show the connection between the method of adjoints in optimal control to the implicit function theorem ansatz. We relate the costate or adjoint state variable to Lagrange multipliers.

From playlist There and Back Again: A Tale of Slopes and Expectations (NeurIPS-2020 Tutorial)

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Data-Driven Control: The Goal of Balanced Model Reduction

In this lecture, we discuss the overarching goal of balanced model reduction: Identifying key states that are most jointly controllable and observable, to capture the most input—output energy. https://www.eigensteve.com/

From playlist Data-Driven Control with Machine Learning

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Another Go at Language Design

(April 28, 2010) Rob Pike, a Principal Engineer at Google, Inc., discusses possible reasons why new computer languages keep appearing and why they led Google engineers to define yet another language, Go. Stanford University: http://www.stanford.edu/ Stanford School of Engineering: http:/

From playlist Engineering

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LoneStarRuby 2015 Phoenix - Productive. Reliable. Fast. by Chris McCord

Phoenix is an Elixir web framework for building productive, reliable applications with the performance to take on the modern computing world. Together, we’ll review what makes Phoenix great and how it uses Elixir to optimize code for performance – without sacrificing programmer productivit

From playlist LoneStarRuby 2015

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Eigenvalues and Modes of Linear Systems

In this video we discuss how the eigenvalues of the A matrix lead to the modes of a linear state space system. We will also examine how to chose initial conditions to excite a specific mode. In other words, we use a carefully chosen initial condition to ensure that the state response of

From playlist Control Theory

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Multiversion concurrency control | Concurrency control | Software transactional memory | Kubernetes | Edit conflict | Linearizability