And are you going for programming roles or software engineering/development roles? Make sure you understand the difference because the latter is far more involved.
It seems to me that developers are always looking for talented young programmers. We're out here looking for you too. Am I missing something?"
If you really are a talented programmer then you have loads of experience proving it - personal folio of projects, contributions to open source, volunteer or paid industry experience from throughout your course - these are the essential things. If you have no experience you'll forgive employers for not taking your claim as being a 'talented programmer' seriously.
I'd give it a try if Apple 'blessed' it (which I doubt they will considering how 'fair' they are)
They better, or Apple will end up like MS with EU slapping penalties and making demands.
No they won't, and personally i reckon that's rubbish, but it's because they don't have a monopoly in that market. Infact Microsoft could do the same in the console, smartphone or portable media player market, just not in the OS market. It's just crap that the same anti-competitive behavior is only illegal if the company has a monopoly.
You might as well say - for example - it's ok for a car manufacturer to mandate that your car can ONLY be serviced at the dealership and you can ONLY fill up with fuel from selected petrol stations.
You guy's are ignorant and stobborn.
For f sake With GCD and blocks I can make my Hello World! App multi threadded and run in optimal amount's of threads on unkonwn hardware specs.
Let's see it then...what part of 'Hello World' are you running concurrently?!
Steve is selling a device, not a browser. If opera wants to compete, they can do it by making their own phone, or by trying to sell Opera on any open devices out there. Nothing new here.
It's like saying "Whirlpool doesn't compete" because I can't load my own software onto my dishwasher. Yeah, no duh dumbass.
MS is selling an operating system, not a browser. If Opera wants to compete they can do it by making their own operating system or by trying to sell opera on any open source operating systems out there. Nothing new here.
Yes there are, just as they apply to microsoft with regard to things like the bundling of internet explorer. These laws are called Anti-trust laws, however they ONLY apply to companies considered to have a monopoly on a market. So absolutely Apple would be demolished in the courts if it were to ever gain a monopolistic position in the smartphone market with the iphone, however unfortunately that same behavior is not considered illegal if the company does not have a monopoly in that market.
"Threading is not difficult, the difficulty comes in parallelising the problem and this must be done regardless of who does the thread management."
No, the problem is synchronization. Threading is not difficult if you don't need or don't care about synchronization, but odds are that if you aren't paying attention to that you aren't really getting performance out of your threading. And most either don't pay sufficient attention or don't know how.
And of course the synchronization part is where the parallel-ized parts of the problem come together. Hence it is the actual splitting of the problem into parallel parts that is the difficult part, the actual implementation of synchronization is easy if you have designed a well parallel-ized application, but that design is the very difficult part.
Once you have your well-designed parallel-ized version of your problem what is the difficulty you're having with synchronization?
You're still doing it manually! With Task Parallel Library you still have to use Parallel.Invoke()!!! And if you want parallelism, you still have to take the trouble to use PLINQ.
It just doesn't compare. It doesn't even approach having threading and thread management built into the OS. And I never claimed that it was the most efficient. But it is still the only mainstream OS that does that. At all.
And in GDC you still have to get a reference to a dispatch queue and call dispatch_async when you want to run a block in another thread. You're still doing things manually, you still have to determine when to use serial (essentially locking) and concurrent queues, you still have a semaphore construct you have to control, it's not magically doing concurrency for you.
If this begins to sound a lot like Apple's solution, that's not surprise. Microsoft can easily make their own version/flavor if they so wish. There's plenty of room in the marketplace to complete.
But Apple's core business is hardware, they rely on being able to bundle hardware and software as a product and have viciously been protecting their questionable practice of tying their software to their hardware because they know if they lose that tying then the 'apple tax' goes away. Microsoft's core business is software, if they make a product that is compatible with the all the unix and unix-like operating systems then they end up in furious competition with free alternatives, the predominant reason that prevents people who would potentially switch to, say Ubuntu, from switching is the incompatibility of applications.
But if they do nothing and wait until Windows 9 Windows 10 to make this move (8 is as soon as they could do it- maybe 2 years from now) they will be dead and forgotten.
A perfect example of this is Epson. They were #1 in printing and printers for almost two decades. They had a lock on the market and it was considered law that it would always be that way. Then a small upstart named HP came along and bet everything on a new technology. Within a few years the entire industry had bailed on Epson and moved to inkjet technology. Epson went from being #1 to just another small player in a field of many.
Except that changing from Epson to HP is easy, it's not like you have a bunch of critical software that will only print on Epson printers. It's not as though 90%+ of new printers are Epson by default then you can - if you want - switch to HP.
Note "earlier version of OS X" i.e., those without GCD.
I've never used DCOM, but it's supposed to be a simple extension of COM and there's a big difference in usability between COM and the NeXt distributed objects.
Yes i agree in terms of usability distributed objects were easier than DCOM, or even CORBA, but the tying to the Obj-C runtime back when Obj-C wasn't very popular is what caused next's implementation of distributed objects to not have much of an impact and not be seen as any better than DCOM or CORBA. Ease of use is one thing, domain of use is another.
Very little helps with concurrency problems. Ease of communication and setting up threads and processes is important as well.
Which would be GCD on OSX (snow leopard) or TPL & PLINQ for.Net, PPL for Windows Native apps (which sits between full thread control and a more declarative model like that used in OpenMP) and the higher level cross-platform OpenMP.
I think it's actually distributed objects, not shared.
I'm fairly sure it is, shared-objects are basically a singleton pattern implementation.
He's talking about the Distributed Objects mechanism, which depends on some features of the Objective-C runtime and the Foundation framework. It comes from NeXT and there's been a working GNUstep implementation for about 15 years too. It allows you to publish an object and then send it messages from another process (optionally on another machine) in exactly the same way that you would with a local object. It's very powerful; you can decompose a large program into several processes using it and have them communicate transparently.
Ah yes, well that still isn't a concurrency solution though, shared mutable state is what makes parallel processing difficult. Distributed objects is a similar concept to DCOM, certainly not game-changing in terms of OS concurrency.
Apple's decision to put provision for this in their Snow Leopard OS is a clear demonstration of their forward (and practical) thinking. Where are all the others?
Apple aren't ahead of the curve on this, TPL and PLINQ were available before GCD was. Not sure why you're trumpeting their Thread-pool (yes the idea has been around for a long time, as have implementations) and scheduler so much. Threading abstractions are not new. And it absolutely is not any kind of solution to the core concurrency problem of splitting a serial problem into smaller parallel tasks. It seems to me you don't quite understand the issue here or what GCD actually is, because it really isn't anything revolutionary.
The issue is who does the thread management, the programmer or the OS?
The issue is working out how to break up inherently serial problems into smaller parallel problems. Threading is not difficult, the difficulty comes in parallelising the problem and this must be done regardless of who does the thread management.
Completely wrong on the first two counts, and the third is irrelevant. Here is why: Grand Central Dispatch is not a "thread manager" in the sense you mean. It makes and manages threads on its own, rather than relying on the programmer to handle them in inside the application.
Correct, it's a thread-pool. Which means it still relies on the application programmer to actually parallelise the problem. GCD doesn't magically create parallelism, it simply manages the threads themselves.
It creates and manages threads on its own, even in applications that are not written to be threaded..
What do you mean by managing threads even for applications that are not written to be threaded? If they are not written to be threaded - or to take advantage of GCD - then what exactly does it do for those applications?
With little work you can make some very nice distributed applications.
That's just use of a global context, and sure you can share that between threads and even processes but that doesn't help with concurrency problem, infact it exacerbates the problem, creating yet more shared mutable state.
I'm not sure if Windows has something similar, but the shared object system in ObjC/Cocoa is pretty fantastic. I think it's inherited from NeXt, so I suspect it's been in OS X all along. Nobody seems to know anything about it though.
AFAIK a cocoa shared-object is just a singleton, it's not a feature of the platform, it's just a pattern.
Now if we can just get rid of this Stephen Conroy idiot, maybe Australia won't be a laughing stock for tech news and articles for a while again.
If possible please help to get the word out to send emails of support to Joe Hockey, an MP who has strongly and vocally opposed the internet filter and is doing a damn good job! If we as a community show support so such people im sure they are likely to continue with those actions!
That would require quite a breakthrough, either in battery or processor tech.
Apparently we have that. The new ARM processors when put with the new hardware decoders are capable of this, as we'll see. Apparently Apple was waiting for just this breakthrough to enable this platform and as soon as it was able, made it.
It's not just the power required by the processor to decode it but also 10hours powering a ~10" LCD screen.
All of this 'think of the children' stuff is aimed to censor the world at the expense of freedom for bad parents who didn't 'think of the children' before they decided to have a family that they aren't capable - or aren't willing to - look after. It's about giving lazy parents another break.
That's the beauty of our current state of cultural development; People are allowed to make stupid decisions for rubbish reasons. It's their money, after all.
That's just your opinion, there are people who would call your decision to use windows 'stupid' and the reasons for it 'rubbish', yet the majority would disagree.
I certainly agree with you but the fact is that most people don't, or more likely don't care enough to take up a position on it. Voting with your wallet only works if the majority does it, and i'd wager a fair percentage of gamers who are opposed to that awful DRM in Assassin's Creed 2 have still bought the game and put up with it.
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I can program!
And are you going for programming roles or software engineering/development roles? Make sure you understand the difference because the latter is far more involved.
It seems to me that developers are always looking for talented young programmers. We're out here looking for you too. Am I missing something?"
If you really are a talented programmer then you have loads of experience proving it - personal folio of projects, contributions to open source, volunteer or paid industry experience from throughout your course - these are the essential things. If you have no experience you'll forgive employers for not taking your claim as being a 'talented programmer' seriously.
I'd give it a try if Apple 'blessed' it (which I doubt they will considering how 'fair' they are)
They better, or Apple will end up like MS with EU slapping penalties and making demands.
No they won't, and personally i reckon that's rubbish, but it's because they don't have a monopoly in that market. Infact Microsoft could do the same in the console, smartphone or portable media player market, just not in the OS market. It's just crap that the same anti-competitive behavior is only illegal if the company has a monopoly.
Yeah, and Apple is going to remove it "fast as a rocket" too.
So sure about that? What about all the other web browsers on the iPhone?
You might as well say - for example - it's ok for a car manufacturer to mandate that your car can ONLY be serviced at the dealership and you can ONLY fill up with fuel from selected petrol stations.
You guy's are ignorant and stobborn. For f sake With GCD and blocks I can make my Hello World! App multi threadded and run in optimal amount's of threads on unkonwn hardware specs.
Let's see it then...what part of 'Hello World' are you running concurrently?!
Apple will say that it duplicates existing iPhone functions and will refuse to accept it.
But lets all keep saying Microsoft is evil.
How do you know that? There are plenty of other web browsers available on the iphone, why reject Opera?
Steve is selling a device, not a browser. If opera wants to compete, they can do it by making their own phone, or by trying to sell Opera on any open devices out there. Nothing new here.
It's like saying "Whirlpool doesn't compete" because I can't load my own software onto my dishwasher. Yeah, no duh dumbass.
MS is selling an operating system, not a browser. If Opera wants to compete they can do it by making their own operating system or by trying to sell opera on any open source operating systems out there. Nothing new here.
Yes there are, just as they apply to microsoft with regard to things like the bundling of internet explorer. These laws are called Anti-trust laws, however they ONLY apply to companies considered to have a monopoly on a market. So absolutely Apple would be demolished in the courts if it were to ever gain a monopolistic position in the smartphone market with the iphone, however unfortunately that same behavior is not considered illegal if the company does not have a monopoly in that market.
"Threading is not difficult, the difficulty comes in parallelising the problem and this must be done regardless of who does the thread management." No, the problem is synchronization. Threading is not difficult if you don't need or don't care about synchronization, but odds are that if you aren't paying attention to that you aren't really getting performance out of your threading. And most either don't pay sufficient attention or don't know how.
And of course the synchronization part is where the parallel-ized parts of the problem come together. Hence it is the actual splitting of the problem into parallel parts that is the difficult part, the actual implementation of synchronization is easy if you have designed a well parallel-ized application, but that design is the very difficult part.
Once you have your well-designed parallel-ized version of your problem what is the difficulty you're having with synchronization?
You're still doing it manually! With Task Parallel Library you still have to use Parallel.Invoke()!!! And if you want parallelism, you still have to take the trouble to use PLINQ. It just doesn't compare. It doesn't even approach having threading and thread management built into the OS. And I never claimed that it was the most efficient. But it is still the only mainstream OS that does that. At all.
And in GDC you still have to get a reference to a dispatch queue and call dispatch_async when you want to run a block in another thread. You're still doing things manually, you still have to determine when to use serial (essentially locking) and concurrent queues, you still have a semaphore construct you have to control, it's not magically doing concurrency for you.
If this begins to sound a lot like Apple's solution, that's not surprise. Microsoft can easily make their own version/flavor if they so wish. There's plenty of room in the marketplace to complete.
But Apple's core business is hardware, they rely on being able to bundle hardware and software as a product and have viciously been protecting their questionable practice of tying their software to their hardware because they know if they lose that tying then the 'apple tax' goes away. Microsoft's core business is software, if they make a product that is compatible with the all the unix and unix-like operating systems then they end up in furious competition with free alternatives, the predominant reason that prevents people who would potentially switch to, say Ubuntu, from switching is the incompatibility of applications.
But if they do nothing and wait until Windows 9 Windows 10 to make this move (8 is as soon as they could do it- maybe 2 years from now) they will be dead and forgotten.
A perfect example of this is Epson. They were #1 in printing and printers for almost two decades. They had a lock on the market and it was considered law that it would always be that way. Then a small upstart named HP came along and bet everything on a new technology. Within a few years the entire industry had bailed on Epson and moved to inkjet technology. Epson went from being #1 to just another small player in a field of many.
Except that changing from Epson to HP is easy, it's not like you have a bunch of critical software that will only print on Epson printers. It's not as though 90%+ of new printers are Epson by default then you can - if you want - switch to HP.
Sigh.
?
Note "earlier version of OS X" i.e., those without GCD.
I've never used DCOM, but it's supposed to be a simple extension of COM and there's a big difference in usability between COM and the NeXt distributed objects.
Yes i agree in terms of usability distributed objects were easier than DCOM, or even CORBA, but the tying to the Obj-C runtime back when Obj-C wasn't very popular is what caused next's implementation of distributed objects to not have much of an impact and not be seen as any better than DCOM or CORBA. Ease of use is one thing, domain of use is another.
Very little helps with concurrency problems. Ease of communication and setting up threads and processes is important as well.
Which would be GCD on OSX (snow leopard) or TPL & PLINQ for .Net, PPL for Windows Native apps (which sits between full thread control and a more declarative model like that used in OpenMP) and the higher level cross-platform OpenMP.
I think it's actually distributed objects, not shared.
In that case the windows version would be DCOM.
Umm, no.
I'm fairly sure it is, shared-objects are basically a singleton pattern implementation.
He's talking about the Distributed Objects mechanism, which depends on some features of the Objective-C runtime and the Foundation framework. It comes from NeXT and there's been a working GNUstep implementation for about 15 years too. It allows you to publish an object and then send it messages from another process (optionally on another machine) in exactly the same way that you would with a local object. It's very powerful; you can decompose a large program into several processes using it and have them communicate transparently.
Ah yes, well that still isn't a concurrency solution though, shared mutable state is what makes parallel processing difficult. Distributed objects is a similar concept to DCOM, certainly not game-changing in terms of OS concurrency.
Apple's decision to put provision for this in their Snow Leopard OS is a clear demonstration of their forward (and practical) thinking. Where are all the others?
Apple aren't ahead of the curve on this, TPL and PLINQ were available before GCD was. Not sure why you're trumpeting their Thread-pool (yes the idea has been around for a long time, as have implementations) and scheduler so much. Threading abstractions are not new. And it absolutely is not any kind of solution to the core concurrency problem of splitting a serial problem into smaller parallel tasks. It seems to me you don't quite understand the issue here or what GCD actually is, because it really isn't anything revolutionary.
The issue is who does the thread management, the programmer or the OS?
The issue is working out how to break up inherently serial problems into smaller parallel problems. Threading is not difficult, the difficulty comes in parallelising the problem and this must be done regardless of who does the thread management.
You missed the point. With Windows (XP, Vista, or 7), you, as a programmer, have to explicitly handle threads.
No you do not. You can use the Task Parallel Library and PLINQ.
Completely wrong on the first two counts, and the third is irrelevant. Here is why: Grand Central Dispatch is not a "thread manager" in the sense you mean. It makes and manages threads on its own, rather than relying on the programmer to handle them in inside the application.
Correct, it's a thread-pool. Which means it still relies on the application programmer to actually parallelise the problem. GCD doesn't magically create parallelism, it simply manages the threads themselves.
It creates and manages threads on its own, even in applications that are not written to be threaded..
What do you mean by managing threads even for applications that are not written to be threaded? If they are not written to be threaded - or to take advantage of GCD - then what exactly does it do for those applications?
With little work you can make some very nice distributed applications.
That's just use of a global context, and sure you can share that between threads and even processes but that doesn't help with concurrency problem, infact it exacerbates the problem, creating yet more shared mutable state.
I'm not sure if Windows has something similar, but the shared object system in ObjC/Cocoa is pretty fantastic. I think it's inherited from NeXt, so I suspect it's been in OS X all along. Nobody seems to know anything about it though.
AFAIK a cocoa shared-object is just a singleton, it's not a feature of the platform, it's just a pattern.
Now if we can just get rid of this Stephen Conroy idiot, maybe Australia won't be a laughing stock for tech news and articles for a while again.
If possible please help to get the word out to send emails of support to Joe Hockey, an MP who has strongly and vocally opposed the internet filter and is doing a damn good job! If we as a community show support so such people im sure they are likely to continue with those actions!
That would require quite a breakthrough, either in battery or processor tech.
Apparently we have that. The new ARM processors when put with the new hardware decoders are capable of this, as we'll see. Apparently Apple was waiting for just this breakthrough to enable this platform and as soon as it was able, made it.
It's not just the power required by the processor to decode it but also 10hours powering a ~10" LCD screen.
You deserve many many modpoints!
All of this 'think of the children' stuff is aimed to censor the world at the expense of freedom for bad parents who didn't 'think of the children' before they decided to have a family that they aren't capable - or aren't willing to - look after. It's about giving lazy parents another break.
They say that you should put your money where your mouth is: I did, and I now have £150 I wouldn't otherwise have (2 x Windows 7 Home license).
So how much of the Always-On Ubisoft DRM affects you then?
That's the beauty of our current state of cultural development; People are allowed to make stupid decisions for rubbish reasons. It's their money, after all.
That's just your opinion, there are people who would call your decision to use windows 'stupid' and the reasons for it 'rubbish', yet the majority would disagree.
I certainly agree with you but the fact is that most people don't, or more likely don't care enough to take up a position on it. Voting with your wallet only works if the majority does it, and i'd wager a fair percentage of gamers who are opposed to that awful DRM in Assassin's Creed 2 have still bought the game and put up with it.