This document provides information about threads and concurrency in computing. It discusses that modern computers have multiple processor cores and that programs can have multiple threads of execution running simultaneously. This leads to concurrency where threads reference shared data, which can cause problems like race conditions where threads interfere with each other's access of data and deadlocks where threads are waiting for resources held by other threads. The document gives examples of how threads and race conditions work in Java code. It explains how to create new threads that extend the Thread class or implement the Runnable interface.
This document discusses multithreading and concurrency in Java. It defines a thread as a single sequential flow of control within a program. Multithreading allows a single processor to run multiple threads concurrently by rapidly switching between them. Creating threads in Java involves either extending the Thread class or implementing the Runnable interface. The document outlines thread states like new, ready, running, blocked, and finished. It also discusses thread scheduling, priorities, synchronization to prevent race conditions, and thread pools for managing tasks.
This document provides an overview of concurrency in Python using multiprocessing and threading. It begins by introducing the speaker and defining key terms like concurrency, threads, and processes. It then discusses the benefits and use cases of threads versus processes. The document also covers the Global Interpreter Lock (GIL) in Python and how multiprocessing can help avoid it. It provides an example benchmark showing multiprocessing can significantly outperform threading for CPU-bound tasks. Finally, it discusses key aspects of Python's multiprocessing module like Process, Queue, Pool, and Manager classes.
The document discusses parallel programming in .NET. It covers two main strategies for parallelism - data parallelism and task parallelism. For data parallelism, it describes using Parallel.For to partition work over collections. For task parallelism, it discusses using the Task Parallel Library to create and run independent tasks concurrently, allowing work to be distributed across multiple processors. It provides examples of creating tasks implicitly with Parallel.Invoke and explicitly by instantiating Task objects and passing delegates.
This document discusses multithreaded programming in Java. It covers two main approaches for creating threads: extending the Thread class or implementing the Runnable interface. Common thread problems like race conditions are addressed, as are techniques for synchronizing access to shared resources using synchronized blocks and methods. The thread lifecycle and useful thread methods like start(), sleep(), join(), etc. are outlined. Signaling with wait() and notify() is demonstrated as a way for threads to communicate. Overall, the document provides an overview of multithreaded concepts in Java and best practices for writing multithreaded programs.
This document discusses Java threads and multithreading. It begins by defining multitasking as allowing multiple programs to run concurrently, while multithreading refers to multiple threads of control within a single program. It notes that threads allow maintaining responsiveness during long tasks and enabling cancellation of separable tasks. The document then covers creating and managing threads in Java by extending the Thread class or implementing Runnable, and describes thread states, priorities, and daemon threads.
Apache Storm is a distributed real-time computation system for processing large amounts of data in real-time. It is fault-tolerant and guarantees message processing. Storm topologies consist of spouts that emit streams of data and bolts that consume and process the streams. Storm provides a simple programming model and is scalable, fault-tolerant, and guarantees processing.
maXbox Starter 42 Multiprocessing Programming Max Kleiner
The document discusses multiprocessing and multithreading programming. It begins by explaining the difference between multiprocessing and multithreading. Multiprocessing uses separate processes that are isolated from each other by the OS, while multithreading runs multiple threads within the same process. It then provides an example code showing how to launch multiple processes asynchronously on different CPU cores using the ExecuteProcess and ExecuteMultiProcessor API calls. The document continues explaining concepts like blocking vs non-blocking calls, threads, and playing sounds asynchronously vs synchronously. It provides examples of playing multiple sounds simultaneously using different approaches.
Google: Cluster computing and MapReduce: Introduction to Distributed System D...tugrulh
This document provides an overview of a distributed computing seminar. The seminar covers 5 lectures including an introduction to distributed computing, MapReduce and GFS, and algorithms for distributed computing. It discusses how distributed computing allows larger problems to be solved by splitting work across multiple computers. Key challenges include parallelizing work, synchronizing access to shared resources, and networking between machines. Synchronization techniques like semaphores and condition variables are introduced to coordinate parallel threads.
This document discusses multithreading and concurrency in Java. It defines a thread as a single sequential flow of control within a program. Multithreading allows a single processor to run multiple threads concurrently by rapidly switching between them. Creating threads in Java involves either extending the Thread class or implementing the Runnable interface. The document outlines thread states like new, ready, running, blocked, and finished. It also discusses thread scheduling, priorities, synchronization to prevent race conditions, and thread pools for managing tasks.
This document provides an overview of concurrency in Python using multiprocessing and threading. It begins by introducing the speaker and defining key terms like concurrency, threads, and processes. It then discusses the benefits and use cases of threads versus processes. The document also covers the Global Interpreter Lock (GIL) in Python and how multiprocessing can help avoid it. It provides an example benchmark showing multiprocessing can significantly outperform threading for CPU-bound tasks. Finally, it discusses key aspects of Python's multiprocessing module like Process, Queue, Pool, and Manager classes.
The document discusses parallel programming in .NET. It covers two main strategies for parallelism - data parallelism and task parallelism. For data parallelism, it describes using Parallel.For to partition work over collections. For task parallelism, it discusses using the Task Parallel Library to create and run independent tasks concurrently, allowing work to be distributed across multiple processors. It provides examples of creating tasks implicitly with Parallel.Invoke and explicitly by instantiating Task objects and passing delegates.
This document discusses multithreaded programming in Java. It covers two main approaches for creating threads: extending the Thread class or implementing the Runnable interface. Common thread problems like race conditions are addressed, as are techniques for synchronizing access to shared resources using synchronized blocks and methods. The thread lifecycle and useful thread methods like start(), sleep(), join(), etc. are outlined. Signaling with wait() and notify() is demonstrated as a way for threads to communicate. Overall, the document provides an overview of multithreaded concepts in Java and best practices for writing multithreaded programs.
This document discusses Java threads and multithreading. It begins by defining multitasking as allowing multiple programs to run concurrently, while multithreading refers to multiple threads of control within a single program. It notes that threads allow maintaining responsiveness during long tasks and enabling cancellation of separable tasks. The document then covers creating and managing threads in Java by extending the Thread class or implementing Runnable, and describes thread states, priorities, and daemon threads.
Apache Storm is a distributed real-time computation system for processing large amounts of data in real-time. It is fault-tolerant and guarantees message processing. Storm topologies consist of spouts that emit streams of data and bolts that consume and process the streams. Storm provides a simple programming model and is scalable, fault-tolerant, and guarantees processing.
maXbox Starter 42 Multiprocessing Programming Max Kleiner
The document discusses multiprocessing and multithreading programming. It begins by explaining the difference between multiprocessing and multithreading. Multiprocessing uses separate processes that are isolated from each other by the OS, while multithreading runs multiple threads within the same process. It then provides an example code showing how to launch multiple processes asynchronously on different CPU cores using the ExecuteProcess and ExecuteMultiProcessor API calls. The document continues explaining concepts like blocking vs non-blocking calls, threads, and playing sounds asynchronously vs synchronously. It provides examples of playing multiple sounds simultaneously using different approaches.
Google: Cluster computing and MapReduce: Introduction to Distributed System D...tugrulh
This document provides an overview of a distributed computing seminar. The seminar covers 5 lectures including an introduction to distributed computing, MapReduce and GFS, and algorithms for distributed computing. It discusses how distributed computing allows larger problems to be solved by splitting work across multiple computers. Key challenges include parallelizing work, synchronizing access to shared resources, and networking between machines. Synchronization techniques like semaphores and condition variables are introduced to coordinate parallel threads.
Introduction & Parellelization on large scale clustersSri Prasanna
This document provides an overview of distributed computing and parallelization challenges. It discusses how parallelization can be difficult due to synchronization issues when multiple threads access shared resources. Various synchronization primitives are introduced like semaphores, condition variables, and barriers to help coordinate parallel threads. The challenges of deadlocks are also covered. MapReduce is then introduced as a paradigm that handles data distribution and synchronization challenges for distributed computing problems.
This document outlines the key concepts and objectives covered in Lecture 04 on threads. It introduces processes and threads, defining them as the basic units of execution in operating systems and Java programs respectively. It discusses how multi-processing systems and multi-threading programs allow concurrent execution. The lecture then covers thread fundamentals in Java, including creating and managing threads, and synchronizing access to shared resources using monitors, locks, and wait-notify mechanisms. Students are assigned workshops on the producer-consumer problem and philosophers problem to demonstrate these concurrency concepts.
This document summarizes key concepts from a lecture on threads. It defines processes and threads, explaining that threads exist within processes and allow for multithreaded execution. It covers thread fundamentals in Java, including creating threads by extending Thread or implementing Runnable, and methods like start(), sleep(), and yield(). The document also discusses synchronizing access to shared resources using monitors, and how wait-notify allows threads to pause and resume execution. Homework includes solving producer-consumer and philosophers problems using these threading concepts.
Java Multi Threading Concept
By N.V.Raja Sekhar Reddy
www.technolamp.co.in
Want more...
Like us @ https://www.facebook.com/Technolamp.co.in
subscribe videos @ http://www.youtube.com/user/nvrajasekhar
Modeling the Behavior of Threads in the PREEMPT_RT Linux Kernel Using AutomataDaniel Bristot de Oliveira
This document discusses modeling the behavior of threads in the PREEMPT RT Linux kernel using automata. It proposes an automata-based model to describe and verify thread management code using a modular approach with generators and specifications. The model was integrated with Linux's tracing features, which helped catch an inefficiency bug in the scheduler code and lead to a kernel improvement. Future work includes expanding the model to support interrupts, locks, and multi-core behavior.
This document provides a brief overview of concurrency concepts in Python, focusing on threading. It defines processes and threads, explaining that threads run within a process and can share resources, while processes are independent and communicate via interprocess communication. It discusses why to use concurrency for performance, responsiveness, and non-blocking behavior. It also covers the Global Interpreter Lock in Python and its implications for threading, and provides examples of creating and running threads.
The document discusses intra-machine parallelism and threaded programming. It introduces key concepts like threads, processes, synchronization constructs (locks and condition variables), and challenges like overhead and Amdahl's law. An example of domain decomposition for parallel rendering is presented to demonstrate how to divide a problem into independent tasks and assign them to threads.
This document provides an introduction to concurrency in Java programming. It discusses modifying a word counting program to run in parallel using threads. It covers thread safety, critical sections, synchronized blocks and methods, lock objects, and other concurrency concepts in Java like volatile fields and deadlocks. The document uses examples to illustrate how to design thread-safe classes and properly synchronize access to shared resources between multiple threads.
This document provides an overview of multi-threaded programming in Java. It discusses how to create threads that extend the Thread class or implement the Runnable interface. It describes how asynchronous thread execution can lead to unpredictable ordering. It also covers issues like data races that can occur from concurrent reads and writes to shared memory by multiple threads. The document introduces thread synchronization using locks to avoid data races and provides an example of deadlock that can occur from incorrect lock usage.
This document discusses concurrent programming with real-time operating systems (RTOS). It begins with an overview of RTOS and what they provide to programmers, such as task management, synchronization primitives, and driver packages. It then discusses specific RTOS concepts like tasks, concurrency primitives like semaphores, and common concurrency problems like data races. Examples are given to demonstrate task creation and using semaphores to safely increment a shared variable between tasks. The document concludes with discussing classical concurrency problems like the dining philosophers problem and potential issues that could arise like deadlock or starvation.
This document discusses multithreading and concurrency in .NET. It covers key concepts like processes and threads, and how they relate on an operating system level. It also discusses the Thread Pool, Task Parallel Library (TPL), Tasks, Parallel LINQ (PLINQ), and asynchronous programming patterns in .NET like async/await. Examples are provided for common threading techniques like producer/consumer and using the Timer class. Overall it serves as a comprehensive overview of multithreading and concurrency primitives available in the .NET framework.
Easier, Better, Faster, Safer Deployment with Docker and Immutable ContainersC4Media
Video and slides synchronized, mp3 and slide download available at URL http://bit.ly/1W22OMy.
Jerome Petazzoni explains in detail the advantages of immutable servers, then how to implement them with containers in general, and Docker in particular. Filmed at qconnewyork.com.
Jerome Petazzoni is a senior engineer at Docker, where he helps others to containerize all the things. In another life he built and operated Xen clouds when EC2 was just the name of a plane, developed a GIS to deploy fiber interconnects through the French subway, managed commando deployments of large-scale video streaming systems in bandwidth-constrained environments such as conference centers.
The document discusses multithreaded programming in Python. It covers threads and the threading module, the difference between single-threaded and multithreaded execution, and provides an example of multithreading. Key points include that threads are lightweight processes that can run concurrently within a larger parent process and share resources like memory. The threading module provides higher-level thread management compared to the lower-level thread module.
This document discusses concurrency and threads in Java. It begins by explaining how to create threads using the Thread class or Runnable interface. It then covers thread states, scheduling, and synchronization to prevent race conditions. Key points include how threads can run concurrently but share resources like memory, the use of synchronized methods to allow only one thread access at a time, and monitors that control access to objects.
- Python allows programmers to write multithreaded programs that run multiple threads concurrently for more efficient use of resources and responsiveness.
- The main benefits of multithreading over multiple processes are that threads within a process can share data and resources more easily. Threads also have less memory overhead than processes.
- There are two main modules for multithreading in Python - the older thread module and the newer threading module, which provides more powerful features and methods for managing threads.
This document provides an overview of concurrency and multi-threading concepts in Java. It defines processes and threads, explaining that threads exist within processes and allow for more efficient concurrent execution than multiple processes. The document reviews object-oriented concepts in Java and introduces threads and multi-threading, describing how to create threads by extending Thread or implementing Runnable. It also outlines the Thread class and common thread states like ready, running, blocked, and dead.
Medical Image Processing Strategies for multi-core CPUsDaniel Blezek
This document discusses various strategies for parallelizing medical image processing tasks across multi-core CPUs. It begins with a poll asking about readers' computer hardware and parallel programming experience. It then covers degrees of parallelism from serial to large-scale parallelism. The document presents pragmatic approaches using C/C++ with "bolted on" parallel concepts. It provides a brief introduction to SIMD and focuses on SMP concepts using threads, concurrency, and parallel programming models like OpenMP, TBB, and ITK. It discusses example problems like thresholding images and common errors. It concludes with next steps in parallel computing.
Introduction & Parellelization on large scale clustersSri Prasanna
This document provides an overview of distributed computing and parallelization challenges. It discusses how parallelization can be difficult due to synchronization issues when multiple threads access shared resources. Various synchronization primitives are introduced like semaphores, condition variables, and barriers to help coordinate parallel threads. The challenges of deadlocks are also covered. MapReduce is then introduced as a paradigm that handles data distribution and synchronization challenges for distributed computing problems.
This document outlines the key concepts and objectives covered in Lecture 04 on threads. It introduces processes and threads, defining them as the basic units of execution in operating systems and Java programs respectively. It discusses how multi-processing systems and multi-threading programs allow concurrent execution. The lecture then covers thread fundamentals in Java, including creating and managing threads, and synchronizing access to shared resources using monitors, locks, and wait-notify mechanisms. Students are assigned workshops on the producer-consumer problem and philosophers problem to demonstrate these concurrency concepts.
This document summarizes key concepts from a lecture on threads. It defines processes and threads, explaining that threads exist within processes and allow for multithreaded execution. It covers thread fundamentals in Java, including creating threads by extending Thread or implementing Runnable, and methods like start(), sleep(), and yield(). The document also discusses synchronizing access to shared resources using monitors, and how wait-notify allows threads to pause and resume execution. Homework includes solving producer-consumer and philosophers problems using these threading concepts.
Java Multi Threading Concept
By N.V.Raja Sekhar Reddy
www.technolamp.co.in
Want more...
Like us @ https://www.facebook.com/Technolamp.co.in
subscribe videos @ http://www.youtube.com/user/nvrajasekhar
Modeling the Behavior of Threads in the PREEMPT_RT Linux Kernel Using AutomataDaniel Bristot de Oliveira
This document discusses modeling the behavior of threads in the PREEMPT RT Linux kernel using automata. It proposes an automata-based model to describe and verify thread management code using a modular approach with generators and specifications. The model was integrated with Linux's tracing features, which helped catch an inefficiency bug in the scheduler code and lead to a kernel improvement. Future work includes expanding the model to support interrupts, locks, and multi-core behavior.
This document provides a brief overview of concurrency concepts in Python, focusing on threading. It defines processes and threads, explaining that threads run within a process and can share resources, while processes are independent and communicate via interprocess communication. It discusses why to use concurrency for performance, responsiveness, and non-blocking behavior. It also covers the Global Interpreter Lock in Python and its implications for threading, and provides examples of creating and running threads.
The document discusses intra-machine parallelism and threaded programming. It introduces key concepts like threads, processes, synchronization constructs (locks and condition variables), and challenges like overhead and Amdahl's law. An example of domain decomposition for parallel rendering is presented to demonstrate how to divide a problem into independent tasks and assign them to threads.
This document provides an introduction to concurrency in Java programming. It discusses modifying a word counting program to run in parallel using threads. It covers thread safety, critical sections, synchronized blocks and methods, lock objects, and other concurrency concepts in Java like volatile fields and deadlocks. The document uses examples to illustrate how to design thread-safe classes and properly synchronize access to shared resources between multiple threads.
This document provides an overview of multi-threaded programming in Java. It discusses how to create threads that extend the Thread class or implement the Runnable interface. It describes how asynchronous thread execution can lead to unpredictable ordering. It also covers issues like data races that can occur from concurrent reads and writes to shared memory by multiple threads. The document introduces thread synchronization using locks to avoid data races and provides an example of deadlock that can occur from incorrect lock usage.
This document discusses concurrent programming with real-time operating systems (RTOS). It begins with an overview of RTOS and what they provide to programmers, such as task management, synchronization primitives, and driver packages. It then discusses specific RTOS concepts like tasks, concurrency primitives like semaphores, and common concurrency problems like data races. Examples are given to demonstrate task creation and using semaphores to safely increment a shared variable between tasks. The document concludes with discussing classical concurrency problems like the dining philosophers problem and potential issues that could arise like deadlock or starvation.
This document discusses multithreading and concurrency in .NET. It covers key concepts like processes and threads, and how they relate on an operating system level. It also discusses the Thread Pool, Task Parallel Library (TPL), Tasks, Parallel LINQ (PLINQ), and asynchronous programming patterns in .NET like async/await. Examples are provided for common threading techniques like producer/consumer and using the Timer class. Overall it serves as a comprehensive overview of multithreading and concurrency primitives available in the .NET framework.
Easier, Better, Faster, Safer Deployment with Docker and Immutable ContainersC4Media
Video and slides synchronized, mp3 and slide download available at URL http://bit.ly/1W22OMy.
Jerome Petazzoni explains in detail the advantages of immutable servers, then how to implement them with containers in general, and Docker in particular. Filmed at qconnewyork.com.
Jerome Petazzoni is a senior engineer at Docker, where he helps others to containerize all the things. In another life he built and operated Xen clouds when EC2 was just the name of a plane, developed a GIS to deploy fiber interconnects through the French subway, managed commando deployments of large-scale video streaming systems in bandwidth-constrained environments such as conference centers.
The document discusses multithreaded programming in Python. It covers threads and the threading module, the difference between single-threaded and multithreaded execution, and provides an example of multithreading. Key points include that threads are lightweight processes that can run concurrently within a larger parent process and share resources like memory. The threading module provides higher-level thread management compared to the lower-level thread module.
This document discusses concurrency and threads in Java. It begins by explaining how to create threads using the Thread class or Runnable interface. It then covers thread states, scheduling, and synchronization to prevent race conditions. Key points include how threads can run concurrently but share resources like memory, the use of synchronized methods to allow only one thread access at a time, and monitors that control access to objects.
- Python allows programmers to write multithreaded programs that run multiple threads concurrently for more efficient use of resources and responsiveness.
- The main benefits of multithreading over multiple processes are that threads within a process can share data and resources more easily. Threads also have less memory overhead than processes.
- There are two main modules for multithreading in Python - the older thread module and the newer threading module, which provides more powerful features and methods for managing threads.
This document provides an overview of concurrency and multi-threading concepts in Java. It defines processes and threads, explaining that threads exist within processes and allow for more efficient concurrent execution than multiple processes. The document reviews object-oriented concepts in Java and introduces threads and multi-threading, describing how to create threads by extending Thread or implementing Runnable. It also outlines the Thread class and common thread states like ready, running, blocked, and dead.
Medical Image Processing Strategies for multi-core CPUsDaniel Blezek
This document discusses various strategies for parallelizing medical image processing tasks across multi-core CPUs. It begins with a poll asking about readers' computer hardware and parallel programming experience. It then covers degrees of parallelism from serial to large-scale parallelism. The document presents pragmatic approaches using C/C++ with "bolted on" parallel concepts. It provides a brief introduction to SIMD and focuses on SMP concepts using threads, concurrency, and parallel programming models like OpenMP, TBB, and ITK. It discusses example problems like thresholding images and common errors. It concludes with next steps in parallel computing.
Design and optimization of ion propulsion dronebjmsejournal
Electric propulsion technology is widely used in many kinds of vehicles in recent years, and aircrafts are no exception. Technically, UAVs are electrically propelled but tend to produce a significant amount of noise and vibrations. Ion propulsion technology for drones is a potential solution to this problem. Ion propulsion technology is proven to be feasible in the earth’s atmosphere. The study presented in this article shows the design of EHD thrusters and power supply for ion propulsion drones along with performance optimization of high-voltage power supply for endurance in earth’s atmosphere.
Advanced control scheme of doubly fed induction generator for wind turbine us...IJECEIAES
This paper describes a speed control device for generating electrical energy on an electricity network based on the doubly fed induction generator (DFIG) used for wind power conversion systems. At first, a double-fed induction generator model was constructed. A control law is formulated to govern the flow of energy between the stator of a DFIG and the energy network using three types of controllers: proportional integral (PI), sliding mode controller (SMC) and second order sliding mode controller (SOSMC). Their different results in terms of power reference tracking, reaction to unexpected speed fluctuations, sensitivity to perturbations, and resilience against machine parameter alterations are compared. MATLAB/Simulink was used to conduct the simulations for the preceding study. Multiple simulations have shown very satisfying results, and the investigations demonstrate the efficacy and power-enhancing capabilities of the suggested control system.
Comparative analysis between traditional aquaponics and reconstructed aquapon...bijceesjournal
The aquaponic system of planting is a method that does not require soil usage. It is a method that only needs water, fish, lava rocks (a substitute for soil), and plants. Aquaponic systems are sustainable and environmentally friendly. Its use not only helps to plant in small spaces but also helps reduce artificial chemical use and minimizes excess water use, as aquaponics consumes 90% less water than soil-based gardening. The study applied a descriptive and experimental design to assess and compare conventional and reconstructed aquaponic methods for reproducing tomatoes. The researchers created an observation checklist to determine the significant factors of the study. The study aims to determine the significant difference between traditional aquaponics and reconstructed aquaponics systems propagating tomatoes in terms of height, weight, girth, and number of fruits. The reconstructed aquaponics system’s higher growth yield results in a much more nourished crop than the traditional aquaponics system. It is superior in its number of fruits, height, weight, and girth measurement. Moreover, the reconstructed aquaponics system is proven to eliminate all the hindrances present in the traditional aquaponics system, which are overcrowding of fish, algae growth, pest problems, contaminated water, and dead fish.
An improved modulation technique suitable for a three level flying capacitor ...IJECEIAES
This research paper introduces an innovative modulation technique for controlling a 3-level flying capacitor multilevel inverter (FCMLI), aiming to streamline the modulation process in contrast to conventional methods. The proposed
simplified modulation technique paves the way for more straightforward and
efficient control of multilevel inverters, enabling their widespread adoption and
integration into modern power electronic systems. Through the amalgamation of
sinusoidal pulse width modulation (SPWM) with a high-frequency square wave
pulse, this controlling technique attains energy equilibrium across the coupling
capacitor. The modulation scheme incorporates a simplified switching pattern
and a decreased count of voltage references, thereby simplifying the control
algorithm.
Null Bangalore | Pentesters Approach to AWS IAMDivyanshu
#Abstract:
- Learn more about the real-world methods for auditing AWS IAM (Identity and Access Management) as a pentester. So let us proceed with a brief discussion of IAM as well as some typical misconfigurations and their potential exploits in order to reinforce the understanding of IAM security best practices.
- Gain actionable insights into AWS IAM policies and roles, using hands on approach.
#Prerequisites:
- Basic understanding of AWS services and architecture
- Familiarity with cloud security concepts
- Experience using the AWS Management Console or AWS CLI.
- For hands on lab create account on [killercoda.com](https://killercoda.com/cloudsecurity-scenario/)
# Scenario Covered:
- Basics of IAM in AWS
- Implementing IAM Policies with Least Privilege to Manage S3 Bucket
- Objective: Create an S3 bucket with least privilege IAM policy and validate access.
- Steps:
- Create S3 bucket.
- Attach least privilege policy to IAM user.
- Validate access.
- Exploiting IAM PassRole Misconfiguration
-Allows a user to pass a specific IAM role to an AWS service (ec2), typically used for service access delegation. Then exploit PassRole Misconfiguration granting unauthorized access to sensitive resources.
- Objective: Demonstrate how a PassRole misconfiguration can grant unauthorized access.
- Steps:
- Allow user to pass IAM role to EC2.
- Exploit misconfiguration for unauthorized access.
- Access sensitive resources.
- Exploiting IAM AssumeRole Misconfiguration with Overly Permissive Role
- An overly permissive IAM role configuration can lead to privilege escalation by creating a role with administrative privileges and allow a user to assume this role.
- Objective: Show how overly permissive IAM roles can lead to privilege escalation.
- Steps:
- Create role with administrative privileges.
- Allow user to assume the role.
- Perform administrative actions.
- Differentiation between PassRole vs AssumeRole
Try at [killercoda.com](https://killercoda.com/cloudsecurity-scenario/)
Embedded machine learning-based road conditions and driving behavior monitoringIJECEIAES
Car accident rates have increased in recent years, resulting in losses in human lives, properties, and other financial costs. An embedded machine learning-based system is developed to address this critical issue. The system can monitor road conditions, detect driving patterns, and identify aggressive driving behaviors. The system is based on neural networks trained on a comprehensive dataset of driving events, driving styles, and road conditions. The system effectively detects potential risks and helps mitigate the frequency and impact of accidents. The primary goal is to ensure the safety of drivers and vehicles. Collecting data involved gathering information on three key road events: normal street and normal drive, speed bumps, circular yellow speed bumps, and three aggressive driving actions: sudden start, sudden stop, and sudden entry. The gathered data is processed and analyzed using a machine learning system designed for limited power and memory devices. The developed system resulted in 91.9% accuracy, 93.6% precision, and 92% recall. The achieved inference time on an Arduino Nano 33 BLE Sense with a 32-bit CPU running at 64 MHz is 34 ms and requires 2.6 kB peak RAM and 139.9 kB program flash memory, making it suitable for resource-constrained embedded systems.
Introduction- e - waste – definition - sources of e-waste– hazardous substances in e-waste - effects of e-waste on environment and human health- need for e-waste management– e-waste handling rules - waste minimization techniques for managing e-waste – recycling of e-waste - disposal treatment methods of e- waste – mechanism of extraction of precious metal from leaching solution-global Scenario of E-waste – E-waste in India- case studies.
artificial intelligence and data science contents.pptxGauravCar
What is artificial intelligence? Artificial intelligence is the ability of a computer or computer-controlled robot to perform tasks that are commonly associated with the intellectual processes characteristic of humans, such as the ability to reason.
› ...
Artificial intelligence (AI) | Definitio
2. Prelim room assignments (not yet posted
elsewhere)
5:30. URHG01: netids lac326 to rzt4
5:30. BKL200: netids sa2229 to zz632
plus all conflicts moving from 7:30 to 5:30 exam
--------------------------------
7:30. URHG01: aa2277 to gyz2
7:30. BKL200: hcm58 to ky356
plus all conflicts moving from 5:30 to 7:30 exam
There will be a homework on concurrency.
2
3. CPU Central Processing Unit. Simplified
view
The CPU is the part of the
computer that executes
instructions.
Java: x= x + 2;
Suppose variable x is at
Memory location 800,
Instructions at 10
Machine language:
10: load register 1, 800
11: Add register 1, 2
12: Store register 1, 800
3
Basic uniprocessor-CPU computer.
Black lines indicate data flow, red
lines indicate control flow
From wikipedia
4. Part of Activity Monitor in Gries’s laptop
4
>100 processes are competing for time. Here’s some of them:
5. Clock rate
Clock rate “frequency at which CPU is
running”
Higher the clock rate, the faster
instructions
are executed.
First CPUs: 5-10 Hz
(cycles per second)
Today MacBook Pro 3.5GHz
Your OS can control the
clock rate, slow it down when
idle, speed up when more
5
7. But a fast computer runs hot
Power dissipation rises as square of the clock
rate
Chips were heading toward melting down!
Put more CPUs on a chip:
with four CPUs on one
chip, even if we run each at
half speed we can perform
more overall computations!
7
8. Today: Not one CPU but many
Processing Unit is called a core.
Modern computers have “multiple cores” (processing
units)
Instead of a single CPU (central processing unit) on
the chip 5-10 common. Intel has prototypes with 80!
We often run many programs at the same time
Even with a single core (processing unit), your program
may have more than one thing “to do” at a time
Argues for having a way to do many things at once
8
9. Many programs. Each can have several
“threads of execution”
We often run many programs at the same time
And each program may have several “threads of
execution”
9
Example, in a Paint program,
when you click the pencil tool,
a new thread of execution is
started to call the method to
process it:
Main GUI thread
Process pencil
click
10. Programming a Cluster...
10
• Sometimes you want to write a
program that is executed on
many machines!
• Atlas Cluster (at Cornell):
• 768 cores
• 1536 GB RAM
• 24 TB Storage
• 96 NICs (Network Interface
Controller)
11. Programming a Cluster...
11
Programs like those that simulate
weather have a big array of
points,
At each step of simulation,
calculates whether at each point
based on info at surrounding
points.
Each is on a separate processor.
12. Many processes are executed
simultaneously on your computer
12
• Operating system provides support for multiple
“processes”
• Usually fewer processors than processes
• Processes are an abstraction:
at hardware level, lots of multitasking
–memory subsystem
–video controller
–buses
–instruction prefetching
13. Concurrency
Concurrency refers to a single program in which several
processes, called threads, are running simultaneously
Special problems arise
They reference the same data and can interfere with
each other, e.g. one process modifies a complex
structure like a heap while another is trying to read it
CS2110: we focus on two main issues:
Race conditions
Deadlock
13
14. Race conditions
A “race condition” arises if two or more processes
access the same variables or objects concurrently and
at least one does updates
Example: Processes t1 and t2 x= x + 1; for some
static global x.
Process t1 Process t2
… ...
x= x + 1; x= x + 1;
But x= x+1; is not an “atomic action”: it takes several steps
14
15. Race conditions
LOAD x
ADD 1
STORE x
...
LOAD x
ADD 1
STORE x
Thread t1 Thread t2
15
Suppose x is initially 5
... after finishing, x = 6! We “lost” an update
16. Race conditions
Typical race condition: two processes wanting to change
a stack at the same time. Or make conflicting changes
to a database at the same time.
Race conditions are bad news
Race conditions can cause many kinds of bugs, not
just the example we see here!
Common cause for “blue screens”: null pointer
exceptions, damaged data structures
Concurrency makes proving programs correct much
harder!
16
17. Deadlock
To prevent race conditions, one often requires a process
to “acquire” resources before accessing them, and only
one process can “acquire” a given resource at a time.
Examples of resources are:
A file to be read
An object that maintains a stack, a linked list, a hash
table, etc.
But if processes have to acquire two or more resources
at the same time in order to do their work, deadlock can
occur. This is the subject of the next slides.
17
18. Dining philosopher problem
18
Five philosophers
sitting at a table.
Each repeatedly
does this:
1. think
2. eat
What do they
eat?
spaghetti.
Need TWO forks
to eat spaghetti!
19. Dining philosopher problem
19
Each does
repeatedly :
1. think
2. eat (2 forks)
eat is then:
pick up left fork
pick up right fork
pick up food, eat
put down left fork
put down rght fork
At one point,
they all pick up
their left forks
DEADLOCK!
20. Dining philosopher problem
20
Simple solution to
deadlock:
Number the forks. Pick
up smaller one first
1. think
2. eat (2 forks)
eat is then:
pick up smaller fork
pick up bigger fork
pick up food, eat
put down bigger fork
put down smallerfork
1
2
4
3
5
21. Java: What is a Thread?
A separate “execution” that runs within a single
program and can perform a computational task
independently and concurrently with other threads
Many applications do their work in just a single thread:
the one that called main() at startup
But there may still be extra threads...
... Garbage collection runs in a “background” thread
GUIs have a separate thread that listens for events
and “dispatches” calls to methods to process them
Today: learn to create new threads of our own in Java
21
22. Thread
A thread is an object that “independently computes”
Needs to be created, like any object
Then “started” --causes some method to be called. It
runs side by side with other threads in the same
program; they see the same global data
The actual executions could occur on different CPU
cores, but but don’t have to
We can also simulate threads by multiplexing a
smaller number of cores over a larger number of
threads
22
23. Java class Thread
threads are instances of class Thread
Can create many, but they do consume space & time
The Java Virtual Machine creates the thread that
executes your main method.
Threads have a priority
Higher priority threads are executed preferentially
By default, newly created threads have initial priority
equal to the thread that created it (but priority can be
changed)
23
24. Creating a new Thread (Method 1)
24
class PrimeThread extends Thread {
long a, b;
PrimeThread(long a, long b) {
this.a= a; this.b= b;
}
@Override public void run() {
//compute primes between a and b
...
}
}
PrimeThread p= new PrimeThread(143, 195);
p.start();
overrides
Thread.run()
Call run() directly?
no new thread is used:
Calling thread will run it
Do this and
Java invokes run() in new thread
25. Creating a new Thread (Method 2)
25
class PrimeRun implements Runnable {
long a, b;
PrimeRun(long a, long b) {
this.a= a; this.b= b;
}
public void run() {
//compute primes between a and b
...
}
}
PrimeRun p= new PrimeRun(143, 195);
new Thread(p).start();
26. Example
26
Thread[Thread-0,5,main] 0
Thread[main,5,main] 0
Thread[main,5,main] 1
Thread[main,5,main] 2
Thread[main,5,main] 3
Thread[main,5,main] 4
Thread[main,5,main] 5
Thread[main,5,main] 6
Thread[main,5,main] 7
Thread[main,5,main] 8
Thread[main,5,main] 9
Thread[Thread-0,5,main] 1
Thread[Thread-0,5,main] 2
Thread[Thread-0,5,main] 3
Thread[Thread-0,5,main] 4
Thread[Thread-0,5,main] 5
Thread[Thread-0,5,main] 6
Thread[Thread-0,5,main] 7
Thread[Thread-0,5,main] 8
Thread[Thread-0,5,main] 9
public class ThreadTest extends Thread {
public static void main(String[] args) {
new ThreadTest().start();
for (int i= 0; i < 10; i++) {
System.out.format("%s %dn",
Thread.currentThread(), i);
}
}
public void run() {
for (int i= 0; i < 10; i++) {
System.out.format("%s %dn",
Thread.currentThread(), i);
}
}
}
Thread name, priority, thread group
27. Example
27 Thread[main,5,main] 0
Thread[main,5,main] 1
Thread[main,5,main] 2
Thread[main,5,main] 3
Thread[main,5,main] 4
Thread[main,5,main] 5
Thread[main,5,main] 6
Thread[main,5,main] 7
Thread[main,5,main] 8
Thread[main,5,main] 9
Thread[Thread-0,4,main] 0
Thread[Thread-0,4,main] 1
Thread[Thread-0,4,main] 2
Thread[Thread-0,4,main] 3
Thread[Thread-0,4,main] 4
Thread[Thread-0,4,main] 5
Thread[Thread-0,4,main] 6
Thread[Thread-0,4,main] 7
Thread[Thread-0,4,main] 8
Thread[Thread-0,4,main] 9
public class ThreadTest extends Thread {
public static void main(String[] args) {
new ThreadTest().start();
for (int i= 0; i < 10; i++) {
System.out.format("%s %dn",
Thread.currentThread(), i);
}
}
public void run() {
currentThread().setPriority(4);
for (int i= 0; i < 10; i++) {
System.out.format("%s %dn",
Thread.currentThread(), i);
}
}
}
Thread name, priority, thread group
28. Example
28 Thread[main,5,main] 0
Thread[main,5,main] 1
Thread[main,5,main] 2
Thread[main,5,main] 3
Thread[main,5,main] 4
Thread[main,5,main] 5
Thread[Thread-0,6,main] 0
Thread[Thread-0,6,main] 1
Thread[Thread-0,6,main] 2
Thread[Thread-0,6,main] 3
Thread[Thread-0,6,main] 4
Thread[Thread-0,6,main] 5
Thread[Thread-0,6,main] 6
Thread[Thread-0,6,main] 7
Thread[Thread-0,6,main] 8
Thread[Thread-0,6,main] 9
Thread[main,5,main] 6
Thread[main,5,main] 7
Thread[main,5,main] 8
Thread[main,5,main] 9
public class ThreadTest extends Thread {
public static void main(String[] args) {
new ThreadTest().start();
for (int i= 0; i < 10; i++) {
System.out.format("%s %dn",
Thread.currentThread(), i);
}
}
public void run() {
currentThread().setPriority(6);
for (int i= 0; i < 10; i++) {
System.out.format("%s %dn",
Thread.currentThread(), i);
}}}
Thread name, priority, thread group
30. Terminating Threads is tricky
Easily done... but only in certain ways
Safe way to terminate a thread: return from method
run
Thread throws uncaught exception? whole program
will be halted (but it can take a second or two ... )
Some old APIs have issues: stop(), interrupt(),
suspend(),
destroy(), etc.
Issue: Can easily leave application in a “broken”
internal state.
Many applications have some kind of variable telling
the thread to stop itself.
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31. Threads can pause
When active, a thread is “runnable”.
It may not actually be “running”. For that, a CPU
must schedule it. Higher priority threads could run
first.
A thread can pause
Call Thread.sleep(k) to sleep for k milliseconds
Doing I/O (e.g. read file, wait for mouse input, open
file) can cause thread to pause
Java has a form of locks associated with objects.
When threads lock an object, one succeeds at a time.
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32. Background (daemon) Threads
In many applications we have a notion of “foreground”
and “background” (daemon) threads
Foreground threads are doing visible work, like
interacting with the user or updating the display
Background threads do things like maintaining data
structures (rebalancing trees, garbage collection, etc.)
On your computer, the same notion of background
workers explains why so many things are always
running in the task manager.
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33. Fancier forms of locking
Java developers have created various synchronization
abstract data types
Semaphores: a kind of synchronized counter
(invented by Dijkstra)
Event-driven synchronization
The Windows and Linux and Apple O/S have kernel
locking features, like file locking
But for Java, synchronized is the core mechanism
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34. Summary
Use of multiple processes and multiple threads within
each process can exploit concurrency
Which may be real (multicore) or “virtual” (an
illusion)
When using threads, beware!
Synchronize any shared memory to avoid race
conditions
Synchronize objects in certain order to avoid
deadlocks
Even with proper synchronization, concurrent
programs can have other problems such as
“livelock”
Serious treatment of concurrency is a complex topic
34