mikeash.com: NSBlog

Tags: fridayqna blocks gcdWelcome back to another Friday Q&A. This week I'm departing from my usual user-driven format to present a class I've written for what I'm calling "background timers", and discuss potential uses for it.

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Blocks and GCD in Russian at 2010-06-29 15:22

Tags: blocks gcd translationAlexander Babaev has been kind enough to translate my series of posts on blocks and GCD into Russian for TouchDev.ru. So far he has posted two, Blocks in Objective-C and Intro to Grand Central Dispatch, Part I. Others in the series will be going up in the future. If you happen to speak Russian, check them out!

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Friday Q&A 2009-12-11: A GCD Case Study: Building an HTTP Server at 2009-12-11 23:58

Tags: fridayqna gcd http networking generatorsIt's time for another wintry edition of Friday Q&A. From the comfort of your toasty-warm homes, you can read about building an HTTP server using Grand Central Dispatch, a topic suggested by Steven Degutis.

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Friday Q&A 2009-09-25: GCD Practicum at 2009-09-25 11:52

Tags: fridayqna gcd performance sourcecodeWelcome back to another Friday Q&A. I'm off to C4 today (hope to see you there!) but I've prepared this in advance so everyone stuck at home (or worse, work) can at least have something interesting to read. Over the past four weeks I've introduced Grand Central Dispatch and discussed the various facilities it provides. In Part I I talked about the basics of GCD and how to use dispatch queues. In Part II I discussed how to use GCD to extract more performance from multi-core machines. In Part III I discussed GCD's event dispatching mechanism, and in Part IV I took care of various odds and ends that I hadn't covered before. This week I'm going to examine a practical application of using GCD to speed up the production of thumbnails for a large quantity of images, a topic suggested by Willie Abrams.

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Friday Q&A 2009-09-18: Intro to Grand Central Dispatch, Part IV: Odds and Ends at 2009-09-18 17:23

Tags: fridayqna gcd performanceIt's that time of the week again. Over the past three weeks I've introduced you to the major pieces Grand Central Dispatch, an exciting new API for parallel processing and event handling in Snow Leopard. The first week I covered basic concepts and dispatch queues. The second week I discussed how to use dispatch queues for parallel processing on multi-core computers. The third week I covered GCD's event handling system. This week I'm going to cover various odds and ends which I didn't get to before: dispatch queue suspension and targeting, semaphores, and one-time initialization.

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GCD Is Not Blocks, Blocks Are Not GCD at 2009-09-11 21:27

Tags: gcd rantThere's a lot of discussion going around the internet lately about blocks and Grand Central Dispatch. They're both great new technologies that have seen the light of day with the 10.6 release, and they see a lot of use together. However, a lot of the people discussing blocks and GCD don't seem to understand that they are not, in fact, the same thing, and aren't even really related. I just wanted to make a quick note here to describe exactly what each one is, how they're different, and how they work together.

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Friday Q&A 2009-09-11: Intro to Grand Central Dispatch, Part III: Dispatch Sources at 2009-09-11 15:28

Tags: fridayqna gcd performanceWelcome back to another Friday Q&A. This week I continue the discussion of Grand Central Dispatch from the past two weeks. In the last two weeks I mainly focused on dispatch queues. This week I'm going to examine dispatch sources, how they work, and how to use them.

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Friday Q&A 2009-09-04: Intro to Grand Central Dispatch, Part II: Multi-Core Performance at 2009-09-04 01:51

Tags: fridayqna gcd performanceWelcome back to Friday Q&A. Last week I discussed the basics of Grand Central Dispatch, an exciting new technology in Snow Leopard. This week I'm going to dive deeper into GCD and look at how you can use GCD to take advantage of multi-core processors to speed up computation. This post assumes that you've read last week's edition, so be sure to do that if you haven't already.

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Friday Q&A 2009-08-28: Intro to Grand Central Dispatch, Part I: Basics and Dispatch Queues at 2009-08-28 14:16

Tags: fridayqna gcd performanceWelcome back to Friday Q&A. This week's edition lines up with Apple's release of Snow Leopard, so I'm going to take this opportunity to open up the discussion on previously NDA'd technologies and talk about some of the cool stuff now available in Snow Leopard. For this week I'm going to start what I plan to be an ongoing series on Grand Central Dispatch, a topic suggested by Chris Liscio.

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WWDC 08 Followup at 2008-06-23 01:33

Tags: wwdc gcd opencl llvm clangAs you saw from my last post, I was sorely disappointed in this year's WWDC keynote. Fortunately the rest of the week didn't follow the same trend.

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