Concurrency control algorithms
In software engineering, a spinlock is a lock that causes a thread trying to acquire it to simply wait in a loop ("spin") while repeatedly checking whether the lock is available. Since the thread remains active but is not performing a useful task, the use of such a lock is a kind of busy waiting. Once acquired, spinlocks will usually be held until they are explicitly released, although in some implementations they may be automatically released if the thread being waited on (the one that holds the lock) blocks or "goes to sleep". Because they avoid overhead from operating system process rescheduling or context switching, spinlocks are efficient if threads are likely to be blocked for only short periods. For this reason, operating-system kernels often use spinlocks. However, spinlocks become wasteful if held for longer durations, as they may prevent other threads from running and require rescheduling. The longer a thread holds a lock, the greater the risk that the thread will be interrupted by the OS scheduler while holding the lock. If this happens, other threads will be left "spinning" (repeatedly trying to acquire the lock), while the thread holding the lock is not making progress towards releasing it. The result is an indefinite postponement until the thread holding the lock can finish and release it. This is especially true on a single-processor system, where each waiting thread of the same priority is likely to waste its quantum (allocated time where a thread can run) spinning until the thread that holds the lock is finally finished. Implementing spinlocks correctly is challenging because programmers must take into account the possibility of simultaneous access to the lock, which could cause race conditions. Generally, such an implementation is possible only with special assembly-language instructions, such as atomic test-and-set operations and cannot be easily implemented in programming languages not supporting truly atomic operations. On architectures without such operations, or if high-level language implementation is required, a non-atomic locking algorithm may be used, e.g. Peterson's algorithm. However, such an implementation may require more memory than a spinlock, be slower to allow progress after unlocking, and may not be implementable in a high-level language if out-of-order execution is allowed. (Wikipedia).
What is the "spin" of a particle?
“Spin” is one of the core building blocks of quantum reality, but it is a subtle concept to grasp. Here’s Brian Greene with one way to think about it. Subscribe to our YouTube Channel for all the latest from World Science U. Visit our Website: http://www.worldscienceu.com/ Like us on Fac
From playlist Science Unplugged: Quantum Mechanics
ADULT SPINNER TURBINE TEST Large Scale High RPM helicopter engine part for steam turbine
ADULT SPINNER This is a turbine conversion from a helicopter engine works project. Compressor shaft. Note: I am behind polycarbonate material. http://www.greenpowerscience.com/ Never free spin anything without proper safety protection. Fingers, eyes and other things can be lost.
From playlist DIY ALTERNATOR WIND TURBINE
Spin in quantum mechanics is an incredibly interesting property. However, it can be very difficult to understand what exactly it is. In this video, we dispel some misconceptions about spin as well as answer some of the more frequently asked questions about spin. #physics #quantum
From playlist Quantum Mechanics
Spin Art... centripetal force..."centrifugal" force // Homemade Science with Bruce Yeany
Spin art has been a popular device in the arts and science over the years. It is rather simple, spin a piece of paper at high speeds, splash some paints on it and then stop it and admire the results. It can be a nice piece to start a discussion on the application of centripetal forces,
From playlist Videos in the introduction
Spinlaunch Throw Rockets into Space (with something which looks like Nikola Tesla turbine)!!!
The concept behind that system is simple. Essentially, SpinLaunch wants to get to orbit by using a large, vacuum-sealed chamber and a hypersonic tether to spin a spacecraft at a high enough velocity up to 5000 miles per hour to escape the atmosphere. That means no rocket, no rocket engines
From playlist SPACE
Spinning ring puts surprising twist on familiar physics
Differences in drag cause the ring to switch directions as it wobbles around. Read more http://scim.ag/1FJbRe3
From playlist Materials and technology
Physics, Torque (1 of 13) An Explanation
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From playlist Mechanics
Watch Time Warp Wednesdays at 8 pm ET. http://dsc.discovery.com/videos/time-warp/ Watch the gracefulness of paint on an ink spinner in slow motion.
From playlist Time Warp
Chem 203. Organic Spectroscopy. Lecture 23. Using TOCSY to Elucidate Spin Systems. ROESY
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From playlist Chem 203: Organic Spectroscopy
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From playlist Science Unplugged: General Relativity
Writing an OS in Rust - Part 10 - Heap Allocation
This is my version of Philipp Oppermann's "BlogOS". It's a baremetal operating system that can boot off of a USB stick on any BIOS-compatible machine, which is pretty amazing. I'm going to be following the whole blog, one video at a time, and running the OS using QEMU instead of booting a
From playlist Rust OS
#381 How to work with a Real Time Operating System and is it any good? (FreeRTOS, ESP32)
Using a real operating system to simplify programming with the Arduino IDE. Is this possible and how? Let’s have a closer look! Operating systems were invented to simplify our lives. But, because they need a lot of resources, they only run on reasonable computers like the Raspberry Pi or a
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Crust of Rust: Atomics and Memory Ordering
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Kernel Recipes 2019 - BPF at Facebook
This talk will provide several examples of how Facebook engineers use BPF to scale the networking, prevent denial of service, secure containers, analyze performance. It’s suitable for BPF newbies and experts. Alexei Starovoitov
From playlist Kernel Recipes 2019
Kernel Recipes 2017 - Refactoring the Linux Kernel - Thomas Gleixner
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From playlist Kernel Recipes 2017
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From playlist Chem 203: Organic Spectroscopy
Kernel Recipes 2018 - Evolution and use of relaxed concurrency primitives - Will Deacon
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How did the concept of particles having "spin" arise from experimental studies?
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From playlist Science Unplugged: Quantum Mechanics
Kernel Recipes 2022 - Looking at yourself: Linux Introspection tales
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From playlist Kernel Recipes 2022