Threading Archives - Page 2 of 2

8 February 20179 January 2022

Implementing an Asynchronous Dispatch Queue

Previously, I introduced the concept of dispatch queues. Here’s a quick review of what a dispatch queue is, in case you haven’t read the previous article: The dispatcher contains multiple generic-use threads and a work queue. Threads can dispatch single functional operations to run asynchronously on the dispatch work threads. Apple is encouraging its app …

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6 February 201714 December 2021

Dispatch Queues

Last week's article discussed the problem with threads. But since threads are simply a fact of life with our current development tools, how can we reduce risk and complexity? Apple's solution: general purpose dispatch queues. In Apple's own words: Dispatch queues let you execute arbitrary blocks of code either asynchronously or synchronously with respect to …

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30 January 201714 December 2021

The Problem with Threads

Threads are a fact of life for the modern programmer. They can be found eveywhere, even on embedded systems. However, threads destroy determinism and make it much harder to reliably predict how your program will behave. We are familiar with the types of problems that arise from using threads: mutal exclusion, deadlocks, priority inversion, and …

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