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→‎WTF: seems reasonable to me
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As a programmer of 20 years, I just came to this page wondering what "futxes" are and left none the wiser. Am I stupid or is this page just filled with jargon but no clear normal English explanation? <!-- Template:Unsigned IP --><small class="autosigned">—&nbsp;Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[Special:Contributions/118.174.38.58|118.174.38.58]] ([[User talk:118.174.38.58#top|talk]]) 19:42, 18 June 2017 (UTC)</small> <!--Autosigned by SineBot-->
As a programmer of 20 years, I just came to this page wondering what "futxes" are and left none the wiser. Am I stupid or is this page just filled with jargon but no clear normal English explanation? <!-- Template:Unsigned IP --><small class="autosigned">—&nbsp;Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[Special:Contributions/118.174.38.58|118.174.38.58]] ([[User talk:118.174.38.58#top|talk]]) 19:42, 18 June 2017 (UTC)</small> <!--Autosigned by SineBot-->
: It is a hard thing to describe, as they don't do much on their own. Which is why the summary in the first line is just "building blocks for implementing semaphores", and the rest are details of how they operate. We can then only describe what it is and what can be done on it. I thought that was should be clear enough, they are wait-queues with an atomic integer and a few special operations, which is basically half of a semaphore implementation if you know how semaphores are implemented. Are there anything in particular you stumbled on that could be improved? [[User:Carewolf|Carewolf]] ([[User talk:Carewolf|talk]]) 11:37, 19 June 2017 (UTC)
: It is a hard thing to describe, as they don't do much on their own. Which is why the summary in the first line is just "building blocks for implementing semaphores", and the rest are details of how they operate. We can then only describe what it is and what can be done on it. I thought that was should be clear enough, they are wait-queues with an atomic integer and a few special operations, which is basically half of a semaphore implementation if you know how semaphores are implemented. Are there anything in particular you stumbled on that could be improved? [[User:Carewolf|Carewolf]] ([[User talk:Carewolf|talk]]) 11:37, 19 June 2017 (UTC)
: This article may have evolved since this complaint; to me, it seems to be perfectly understandable to anyone who understands mutexes and semaphores, which are both linked in the first paragraph. [[User:BernardoSulzbach|BernardoSulzbach]] ([[User talk:BernardoSulzbach|talk]]) 09:39, 7 August 2021 (UTC)


== Bugs fixed ==
== Bugs fixed ==

Revision as of 09:39, 7 August 2021

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Benaphore

I've just fixed the reference to benaphores to mention that they're similar, but not the same. Specifically (in case anyone wants to go find reference material and write a paragraph for the article) the Benaphore always requires an OS semaphore, so if you have 1000 Benaphores you need also 1000 of the (relatively scarce) OS semaphores, in addition to the atomic variables, just in case any of your benephores are contended. In contrast if you have 1000 futexes you don't use any kernel resources at all except when one of them is contended.

Linux is also able to promise that futexes will work correctly between processes (because it provides a way for them to map the same RAM), whereas in BeOS the benaphore worked only among threads within a single process. 2001:8B0:FBB0:1247:21A:4DFF:FE96:2C2B (talk) 16:14, 1 June 2013 (UTC)[reply]

WTF

As a programmer of 20 years, I just came to this page wondering what "futxes" are and left none the wiser. Am I stupid or is this page just filled with jargon but no clear normal English explanation? — Preceding unsigned comment added by 118.174.38.58 (talk) 19:42, 18 June 2017 (UTC)[reply]

It is a hard thing to describe, as they don't do much on their own. Which is why the summary in the first line is just "building blocks for implementing semaphores", and the rest are details of how they operate. We can then only describe what it is and what can be done on it. I thought that was should be clear enough, they are wait-queues with an atomic integer and a few special operations, which is basically half of a semaphore implementation if you know how semaphores are implemented. Are there anything in particular you stumbled on that could be improved? Carewolf (talk) 11:37, 19 June 2017 (UTC)[reply]
This article may have evolved since this complaint; to me, it seems to be perfectly understandable to anyone who understands mutexes and semaphores, which are both linked in the first paragraph. BernardoSulzbach (talk) 09:39, 7 August 2021 (UTC)[reply]

Bugs fixed

The "History" section mentions a few instances where futexes introduced bugs into Linux. But there are no mentions of whether those bugs were ever fixed or not. Were they? — Loadmaster (talk) 17:01, 11 April 2018 (UTC)[reply]

Of course they were. Feel free to complete it though. I would just assumed they were fixed before they were announced publically, that is how it usually works.Carewolf (talk) 08:28, 14 April 2018 (UTC)[reply]