Linked by Hadrien Grasland on Fri 27th May 2011 11:34 UTC
After having an interesting discussion with Brendan on the topic of deadlocks in threaded and asynchronous event handling systems (see the comments on this blog post), I just had something to ask to the developers on OSnews: could you live without blocking API calls? Could you work with APIs where lengthy tasks like writing to a file, sending a signal, doing network I/O, etc is done in a nonblocking fashion, with only callbacks as a mechanism to return results and notify your software when an operation is done?
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Linked by Thom Holwerda on 05/24/13 17:26 UTC
So, the Xbox One disaster continues. Microsoft's policy for dealing with the used games market has reportedly leaked - and it's a clear and direct attack to destroy the used games market. Prices for used games will be set at the retail value of a new game, and retailers have to hook into Microsoft's computer systems and comply with Microsoft's terms and conditions.
Linked by Thom Holwerda on 05/21/13 21:38 UTC
At an event earlier today, Microsoft unveiled the next Xbox - the third model, but confusingly named Xbox One. The big focus was TV, integrated Kinect, and all the other stuff we all expected to be forced down our throats. I think it took them 25 minutes to actually come to what should be the core of the story: gaming. Nothing groundbreaking in the gaming department, except for how Microsoft intends to handle the used games market and borrowing games from friends: pay up, buddy!
Linked by Thom Holwerda on 05/20/13 11:29 UTC
The day has finally come! Jolla has finally announced the launch device for its Sailfish operating system - and by god this is a looker. It's decidedly different from other phones out there, but it has good specifications and carries a relatively reasonably price tag - EUR 399, and it's up for pre-order today, shipping in the fourth quarter of this year.
Linked by Thom Holwerda on 05/18/13 21:33 UTC
Why does Google get so much credit in the technology industry? Why, despite the company's many obvious failings, do many geeks and enthusiasts still hold a somewhat positive view on the all-knowing technology giant? A specific talk at Google I/O this week provides the answer.
Linked by David Adams on 05/16/13 4:23 UTC
OSNews is a sponsor of this year's O'Reilly OSCON in Portland, Oregon, USA. A lucky OSNews reader will win a free three-day pass, including two tutorials days. To win the pass, post a comment on this story saying something about Open Source Software or OSCON. We'll pick a winner at random next week. If you don't have an OSNews account, you may email us your entry. Part of the conference is the 9th annual Open Source Awards, and today the 16th is the deadline for nominations. If you'd like to nominate an outstanding open source contributor, do it here. Read on for more information about OSCON. Update: The 20% discount code for OSNews readers is "OSN."
Linked by Thom Holwerda on 05/11/13 21:41 UTC
"Windows is indeed slower than other operating systems in many scenarios, and the gap is worsening." That's one way to start an insider explanation of why Windows' performance isn't up to snuff. Written by someone who actually contributes code to the Windows NT kernel, the comment on Hacker News, later deleted but reposted with permission on Marc Bevand's blog, paints a very dreary picture of the state of Windows development. The root issue? Think of how Linux is developed, and you'll know the answer.
Linked by Thom Holwerda on 05/08/13 14:22 UTC
This is one of those news items that's fun to write, fun to read, fun to comment on, and where no one will be able to say anything unkind. It's all just one big ball of awesome fluffiness. TuneTracker, the BeOS radio automation software, has just released something very special: TuneTracker System 5, the first version designed entirely and specifically for Haiku. In fact, it actually includes Haiku in the software package. Better yet, TuneTracker also unveiled several system-in-a-box products - which have Haiku and TuneTracker pre-installed.
Linked by Thom Holwerda on 05/02/13 15:28 UTC
Exactly twenty years ago, a document was published that played a huge role in establishing the web as we know it today. Twenty years later, and this simple and straightforward document is proof of an irrefutable fact: while closed technologies can change markets, open technologies can change the world.
Linked by Thom Holwerda on 04/29/13 21:06 UTC
Oh multitasking. That staple of computing that got thrown out the window with many modern smartphones. We got some rudimentary thing in its place - but even as multitasking on phone and tablets improves, its user-visible side remains cumbersome. Windows 8 has a neat implementation, and now it's time Android follows in it footsteps.
Linked by Thom Holwerda on 04/24/13 22:24 UTC
They're here! Whether that excites you or not remains to be seen, but the Galaxy S4, which will most likely become the best selling Android smartphone of the year by a huge margin, has been reviewed by all the major sites, and there's lots of interesting conclusions in there - although I think most of you will get the gist.More Features »
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2005-11-16
Hi,
Why need there be any limit at all, short of memory constraints or policy?
There doesn't need to be any hard limit.
In practice, if the limit is too small you end up splitting data into many messages and combining the pieces at the receiving end (and possibly pounding the daylights out of the kernel); and if the message size is too big (or unspecified/unlimited) it's hard to tasks to reserve space for receiving messages, and you risk running out of RAM (e.g. all your free RAM gets tied up in messages in queues).
There's also compatibility issues. For example, imagine a 64-bit kernel capable of running 64-bit processes and 32-bit processes. With no limit, what happens when a 64-bit process sends a 12 GiB message to a 32-bit process?
Locally delivered messages can be guarantied, network messages would depend on the underlying protocols - but how is this any different between threads/async?
Locally delivered messages may not be guaranteed to be received. You send a message to a task, it's placed in that task's queue, then that task terminates or crashes before it gets your message from its queue.
It's using asynchronous messaging and multiple threads; so I'm not sure if that's different to whatever you think "threads/async" is... ;-)
A queued async model doesn't get out of sequence messages, so I'm not sure why your asking this question?
Imagine 3 tasks. Task A sends a message to task B and then sends a message to task C. When task C receives the message from Task A, it sends a message to task B. Can task B receive the message from task C before it receives the message from task A?
In some cases the answer is "yes" - mostly when there's some sort of intermediate buffering/queuing happening before the message reaches the final task's queue (e.g. in networking layers).
- Brendan