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Which is an example of an atomic operation?
Atomic operation. An atomic operation is an operation that will always be executed without any other process being able to read or change state that is read or changed during the operation. It is effectively executed as a single step, and is an important quality in a number of algorithms that deal with multiple indepent processes,…
What is the meaning of atomic in Stack Overflow?
Note that “atomic” is contextual: in this case, the upsert operation only needs to be atomic with respect to operations on the answers table in the database; the computer can be free to do other things as long as they don’t affect (or are affected by) the result of what upsert is trying to do. Thanks for contributing an answer to Stack Overflow!
What does atomic mean in the context of upsert?
Everything works. Note that “atomic” is contextual: in this case, the upsert operation only needs to be atomic with respect to operations on the answers table in the database; the computer can be free to do other things as long as they don’t affect (or are affected by) the result of what upsert is trying to do.
How are atomic operations used in concurrent programming?
In concurrent programming, it means that there will be no context switch during it – nothing can affect the execution of atomic command. An example: a web poll, open-ended questions, but we want to sum up how many people give the same answer. You have a database table where you insert answers and counts of that answer. The code is straightforward:
Can a multiprocessor system guarantee atomic access?
On multiprocessor systems, ensuring atomicity exists is a little harder. It is still possible to use a lock (e.g. a spinlock) the same as on single processor systems, but merely using a single instruction or disabling interrupts will not guarantee atomic access.
Which is the most efficient way to ensure atomicity?
If it is possible, disabling interrupts may be the most efficient method of ensuring atomicity (although note that this may increase the worst-case interrupt latency, which could be problematic if it becomes too long). On multiprocessor systems, ensuring atomicity exists is a little harder.