Limited RAM in Apple's A5 chip in iPad 2, iPhone 4S motivated by battery life concerns

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  • Reply 41 of 70
    Quote:
    Originally Posted by jmillermcp View Post


    Good God man, next time read the freaking article before you go off on a rant. MS was applauding Apple for their memory decisions, not bashing them.



    What do you expect. This place is crawling with Apple-fanatic-idiots. There are quite a number of good Apple folks here too.
  • Reply 42 of 70
    Quote:
    Originally Posted by Corporate View Post


    Yes because you know more about this subject than the ENGINEERS at 2 of the biggest companies in the world....



    I have always said this to my cousin who seems to love the phone with the best specs. I would just say "wats the point of having these 'SUPER GREAT SPECS' if your really not going to use them all that much on the phone, its more efficient to put in the specs NEEDED to perform the tasks that it can"....my point is that all these android fans love their specced out phones but is it really worth it to having a shitload of memory if your batter life is going to be shit? Apple knows how to make use of what they have and somehow still beat out the competiton with better specs, and then to put the their foot a little further up Android's ass they have way better battery life.



    There was a time somewhere between Jaguar and Tiger that OS updates actually felt faster on the same hardware (the RISC days with IBM.) Between Tiger and Leopard, with all of the changes it felt as though Apple forgot how to write sleek code. Then SL came, and people thought that with "no new features" it was a flop, until you realized the bloat was gone and the machines were fast again, all without a hardware upgrade.

    I truly hope for all of us MS has finally gotten the hint; that good code is better than hardware advances. If so, we all win.
  • Reply 43 of 70
    hirohiro Posts: 2,663member
    Quote:
    Originally Posted by Bancho View Post


    How do you figure? The article says in the first line that it's built into the processor. It's all contained in the same "chip" though there are multiple dies within that package. It's a semantic issue at best.



    Hardly. The price paid for going off die, even within the same package is an access time increase of at least 30x or so. Keeping memory on die will eventually be the way of the future, and it will make computers that 30x or so faster all at once. We've got more than a few years before we get there yet.



    The main benefit of packaging the way Apple does is that power requirements are significantly lower because the connections can be better engineered compared to memory off-package connections. Better engineered connections mean less noise and less noise means less signal strength needed which is why the power consumption gets lower.



    So no, it's not semantic issues at all. It's hard fact and precise terminology that immediately identifies the performance regimes.
  • Reply 44 of 70
    hirohiro Posts: 2,663member
    Quote:
    Originally Posted by wizard69 View Post


    The primary issue (more RAM = more power) is accurate to an extent. Dynamic RAM is especially an issue here as you can't stop refreshing it. However there are extensions and considerations that can tip the scales in a different direction. For example if an app has to spend extensive amounts of time accessing secondary store it can have a greater impact on battery life than limiting RAM. Also pressure on RAM can impact responsiveness of the platform.



    Now realize that this is an engineering issue. Each time a process shrink comes along the engineering team has to evaluate where the best place is to get additional advantage from the power savings. That may mean more cores, a better GPU or more RAM. Obviously Apple decided that the weak points in their system architecture was in the CPU and GPU this time around. That might not be the case in the next revision.



    Those reasons are why Apple provides so many stock GUI elements. Sharing the graphics makes an order of magnitude or more improvement in memory efficiency. It's also why Apple suspends programs between invocations as the default way to do business. That saves both from eliminating background running code when it isn't necessary as well as further lowering overall memory requirements, which allows less RAM and again less power draw.
  • Reply 45 of 70
    wizard69wizard69 Posts: 13,377member
    Quote:
    Originally Posted by hill60 View Post


    I remember updating my Mac Plus from 256kb of RAM to an amazing 1Mb.



    I did a science degree with that thing, complete with 20Mb hard drive which cost $3000.



    A slow poke of a computer by today's standards. On the other hand I just loved that little machine as it highlighted why people would want to have such a machine in the house.



    It did however highlight another issue, that is Apples reluctance to offer enough RAam in their machines.
  • Reply 46 of 70
    wizard69wizard69 Posts: 13,377member
    Obviously we won't get the area to implement system RAM but we should have enough die space for video RAM for the GPU. Even if it is just a frame buffer it ought to help a great deal with power savings. After all the GPU constantly accesses memory.



    I suppose the modern approach would be to make the cache bigger. I'm sure that would lead to an interesting discussion amongst engineers. My thing is that moving to retina type displays in an iPad means a lot of data gets accessed for each screen update. Putting that frame buffer outside of normal memory channels just means less congestion on a regular cache.

    Quote:
    Originally Posted by Hiro View Post


    Hardly. The price paid for going off die, even within the same package is an access time increase of at least 30x or so. Keeping memory on die will eventually be the way of the future, and it will make computers that 30x or so faster all at once. We've got more than a few years before we get there yet.



    For anybody interested there is a series on ITunes that goes into chip design. Unfortunately I don't have the exact name but it was offered through Stanford and was part of their computer science offerings.



    In a nut shell you pay big time in access speed and power when going off chip. the question for Apple is the move to the 20nm nodes enough of a shrink to provide room for a reasonably sized RAM array. I suspect not, at least not for general system access. Especially after adding cores and other functionality.

    Quote:

    The main benefit of packaging the way Apple does is that power requirements are significantly lower because the connections can be better engineered compared to memory off-package connections. Better engineered connections mean less noise and less noise means less signal strength needed which is why the power consumption gets lower.



    While you are correct on the technology I think the big advantage for Apple is the ability to crunch a 32 bit computer down to the size of the tiny motherboard inside iPhone. In otherwords physical space is a driving force for this type of hardware. That doesn't mean the advantages you point out aren't important as the have a huge impact on the system. It is just that without the stacked dies iPhone would likely be a much fatter device.

    Quote:

    So no, it's not semantic issues at all. It's hard fact and precise terminology that immediately identifies the performance regimes.



    I'm not happy to see people wallow in ignorance either. For the non technical person simply understanding that there are multiple chips in that A5 package ought to be good enough. In the future we may have 3D technologies that obscure the issues here. For now people need to realizes that A5 is a package of chips.
  • Reply 47 of 70
    Quote:
    Originally Posted by SixnaHalfFeet View Post


    AppleInsider, Can we get the link to the Microsoft blog? It will help with fact checking. Thanks.



    It took me about 15 seconds to google for that link:



    http://blogs.msdn.com/b/b8/archive/2...windows-8.aspx



    I wonder how you want to do "fact checking" without even being able to find that link yourself.



    But then why work yourself when others can do the job for you...
  • Reply 48 of 70
    wizard69wizard69 Posts: 13,377member
    The problem with a system that uses dynamic RAM is that it constantly has to be refreshed. That ends up being a significant power draw for something that might spend most of its day in your pocket. I honestly think the guy from Microsoft was addressing those loads that impact idle battery lifetimes. Let's face it when an app is being ran or used the power demand can vary widely and more importantly the user expects power to be used when the app is in use. What the user doesn't like is his cell phone going dead in his pocket.



    Now here one has to expect that a device will have significant idle periods which many iOS devices do. The always on nature of most iOS devices though require that idle power be minimized as much as possible.



    Quote:
    Originally Posted by Hiro View Post


    Those reasons are why Apple provides so many stock GUI elements. Sharing the graphics makes an order of magnitude or more improvement in memory efficiency. It's also why Apple suspends programs between invocations as the default way to do business. That saves both from eliminating background running code when it isn't necessary as well as further lowering overall memory requirements, which allows less RAM and again less power draw.



  • Reply 49 of 70
    Quote:
    Originally Posted by Andreas71 View Post


    It took me about 15 seconds to google for that link:



    http://blogs.msdn.com/b/b8/archive/2...windows-8.aspx



    I wonder how you want to do "fact checking" without even being able to find that link yourself.



    But then why work yourself when others can do the job for you...



    Thanks for helping the tall youngster, Andreas. It's sad really. In the words of Jed Clampett, "pitiful, just pitiful".
  • Reply 50 of 70
    macslutmacslut Posts: 514member
    Quote:
    Originally Posted by dagamer34 View Post


    The obvious reason for more RAM is so that the phone has to spend less energy getting costly resources over a 3G data connection again. It is important to note that all desktop operating systems are different from their mobile counterparts in that desktops can stick data in RAM onto the hard disk to be used later. Sure, there's a penalty when you have to grab that data from the hard disk again instead of RAM, but it's MUCH better than having to access network resources (and on a mobile device, using 3G is the largest penalty there is).



    As far as I know, none of the mobile operating systems have virtual memory because they don't want to wear out their Flash chips with continuous read/write cycles. Desktops and laptops don't really have this problem. Even Windows 8 tablets will write data to virtual memory.



    So I don't really buy the "less RAM = more power savings" argument on a mobile device. Any savings gained from having less RAM would quickly be wiped out by having to re-download images and other media assets from the web.



    Your comment is wrong on so many levels, it's almost as if you tried.



    3G has nothing to do with RAM. The only data being uses over 3G, WiFi, or any other connection is data that could otherwise be stored via Flash, but isn't because it either needs to be fresh data (what is the weather, stock price, news), or because it takes up too much space (the Netflix library, Wikipedia, Google Maps, etc...).



    Using 512MB or 1GB of RAM would have no impact on connectivity required resources.



    Furthermore, even 3rd party apps are allowed to cache incoming data to Flash, so even assets that are time sensitive, but haven't expired, or are too large, but only represent what was previously needed, can be written and read from Flash.



    The bottom line is that this article is spot on. There are multiple reasons for the decision to use less RAM: 1) Cost 2) Power Savings 3) Size 4) Speed. The last point, speed, is a tricky one, because less RAM will actually increase the speed of the device *IF* the upper threshold of memory usage is not reached and is only of practical significance if the amount of installed RAM that you're comparing it against is overkill.
  • Reply 51 of 70
    macrulezmacrulez Posts: 2,455member
    deleted
  • Reply 52 of 70
    macrulezmacrulez Posts: 2,455member
    deleted
  • Reply 53 of 70
    Quote:
    Originally Posted by mstone View Post


    iPhone sure, but the iPad has volumes of unused space that could accommodate a much larger battery to provide the needed power for the additional RAM. It might make it too heavy, but more RAM is better, in my opinion, as long as you can still deliver the long battery life that we currently enjoy on iPad.



    no, heavy is not better. use a laptop if you want more ram and weight.
  • Reply 54 of 70
    Quote:
    Originally Posted by Corporate View Post


    Yes because you know more about this subject than the ENGINEERS at 2 of the biggest companies in the world....



    I have always said this to my cousin who seems to love the phone with the best specs. I would just say "wats the point of having these 'SUPER GREAT SPECS' if your really not going to use them all that much on the phone, its more efficient to put in the specs NEEDED to perform the tasks that it can"....my point is that all these android fans love their specced out phones but is it really worth it to having a shitload of memory if your batter life is going to be shit? Apple knows how to make use of what they have and somehow still beat out the competiton with better specs, and then to put the their foot a little further up Android's ass they have way better battery life.



    exactly. this is a big beef with me and android hardware. i could care less if it has a 6 core cpu and 4 gig ram blah, blah, blah, blah. get the f***** battery life and weight in order first!
  • Reply 55 of 70
    macrulezmacrulez Posts: 2,455member
    deleted
  • Reply 56 of 70
    macrulezmacrulez Posts: 2,455member
    deleted
  • Reply 57 of 70
    MarvinMarvin Posts: 14,751moderator
    Quote:
    Originally Posted by AppleInsider View Post


    "In any PC, RAM is constantly consuming power. If an OS uses a lot of memory, it can force device manufacturers to include more physical RAM. The more RAM you have on board, the more power it uses, the less battery life you get.



    "Having additional RAM on a tablet device can, in some instances, shave days off the amount of time the tablet can sit on your coffee table looking off but staying fresh and up to date,"



    A Macbook Air doesn't last any longer on battery with 1GB RAM than it does with 4GB. If anything, it's the opposite because not being able to maintain data in RAM requires you to download content again and redraw the screen using wifi, CPU, GPU and Flash memory.



    There is something to be said for efficient use of memory but a lack of RAM is not something we should hope for. Competing tablets/phones can have lower battery life for any number of reasons - using inefficient code, using highly clocked CPUs and GPUs, Adobe Flash support, larger displays with less efficient illumination methods.



    I reckon iPad 3 will have 1GB RAM and I also reckon it won't affect battery life.
  • Reply 58 of 70
    jmmxjmmx Posts: 341member
    Quote:
    Originally Posted by MacRulez View Post




    When Apple adopts true multitasking in iOS 6 the benefits will become self-evident.



    Would you be kind enough to explain what you mean by "true multitasking" and why iOS does not have it?



    ty
  • Reply 59 of 70
    Quote:
    Originally Posted by wizard69 View Post


    The primary issue (more RAM = more power) is accurate to an extent. Dynamic RAM is especially an issue here as you can't stop refreshing it. However there are extensions and considerations that can tip the scales in a different direction. For example if an app has to spend extensive amounts of time accessing secondary store it can have a greater impact on battery life than limiting RAM.



    What you say is undoubtedly true of hard drive based systems, but we are talking about the iPhone here and Dynamic RAM will most likely always consume more power than Flash RAM. Therefore accessing secondary storage will most likely have very little power hit (especially if it is just read cycles) compared to the power hit from increasing Dynamic RAM. As the article points out, Dynamic RAM consumes power whether the RAM is being used or not, whether it is actually holding any data or not. Flash RAM only consumes power when an actual read or write is in progress.
  • Reply 60 of 70
    Quote:
    Originally Posted by Marvin View Post


    I reckon iPad 3 will have 1GB RAM and I also reckon it won't affect battery life.



    I reckon you are correct, but I also reckon that the iPad3 won't be using iPad2 power management or battery size to give the same battery life.
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