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The 808 is also a big little architecture, with two A57 cores and four A53 cores. The A53 cores will likely carry the vast majority of every day use, and redoub

The 808 is also a big little architecture, with two A57 cores and four A53 cores. The A53 cores will likely carry the vast majority of every day use, and redouble the battery savings. As a Nexus 5 user I'm pleased with most of the changes and non-changes. 2GB is fine for a smartphone, and an image sensor with more than double the light capture area per pixel is brilliant, and if it delivers the better photographs will be worth it right there. Losing OIS...I don't think that's a downgrade as OIS was always suspect to begin with (not least because OIS only helps for lateral movements. It does nothing for rotational movements, and of course make subjects stand still. It yielded a tonne of unusable photos). The only thing I'm really displeased about is the removal of wireless charging. That was a really nice feature. Between the Snapdragon 810 and 808, the only real items of concern is that the 808 does not have h265 hardware encoding (the 810 does), and its image processing DSP is 12-bit per pixel rather than the 14-bpp of the 810.

DannyBee 11y ago
"The A53 cores will likely carry the vast majority of every day use, and redouble the battery savings." non-ARM-manufacturer citation needed :). My experience as a compiler guy (that makes the toolchains for these kinds of phones) has been that big little brings improvements to what these guys can shove on a chip and advertise, but so far not real improvements to battery life or real numbers. There reason why is pretty simple. In an ideal world, you don't want anything running at all. You don't want A53's "handling the majority of the workload". What you want is to wake up, do whatever work is needed as fast as possible, and go back to sleep. Period. Sleeping chips are lower power, by far, than idling chips. If it's faster to do that work with an A57, it'll generally give you better battery life to do that. Again, this is right now, based on perf per watt/blah blah blah. Maybe someday, in the future, a53's will be so low power vs a57 that doing something else makes sense. But it's not true now, AFAIK. Instead, they make big-little because they can't really increase the speed of the higher end cores more without increasing power usage too much.
- inversionOf 11y ago
  You don't want A53's "handling the majority of the workload". Yes. You do. If I'm casually browsing non-intensive web pages, e-reading, or watching a Netflix movie, or even encoding a video, the background is doing IO rate limited system updates and basic data logging, etc, the vast majority of the time the CPU demands are very low, but frequent enough that putting a CPU to sleep is completely out of the question. An A53 has a much lower ceiling, but a much better middle tier power usage level, than the A57. Yes, if you want to run a benchmark the A53 is not a good bet (and is generally worse in a workload power usage), but it is a very good bet for most real world usage.
  - DannyBee 11y ago
    No, you don't. Encoding a video should not be CPU, so let's get that out of there. Most of the rest is more GPU dependent than CPU dependent. The amount of CPU time you should be spending on these tasks is really low. For example, web browsing and reading, the CPU should be asleep most of the time. Now, don't get me wrong, there are plenty of very silly little tasks for A53's to do, but what you listed are not those tasks. It's more things like "syncing" or something that is a poll loop and event bound, not something that is in any way CPU bound. Period. CPU bound stuff is not something for the A53's in this to tackle. It makes battery life worse. That is what the actual, in-the-field data says. " a much better middle tier power usage level, than the A57" Truthfully, for most A53 cores, this is true only in the dreams of the chip designers. "but it is a very good bet for most real world usage." Then what, pray tell, do you expect the A57's to be doing in this world? And why, in practice, has big.little and other things not shown any better battery life at all if it's really a better way of doing things. I have no doubt it may be a better way of doing things in the future, but it ain't right now ;)
    - inversionOf 11y ago
      The amount of CPU time you should be spending on these tasks is really low. Which is exactly the point. They are not CPU intensive, but the CPU is constantly doing a multitude of little things, whether simply moving memory around from the GPU to storage, sending the render buffers for the 60fps display, etc. Another comment mentioned, rightly, that cores are put to sleep in they don't have anything to do in a quantum. A quantum is an enormously huge period of time, and is a macro power management technique, and is the last bastion behind idle frequency scaling, and big.little. Truthfully, for most A53 cores, this is true only in the dreams of the chip designers. You have zero expertise to be saying this. I mean, here's how Samsung actually does it on a big/little setup- http://www.androidauthority.com/galaxy-s6-octa-core-processor-usage-617585/ http://www.androidauthority.com/galaxy-s6-octa-core-processo... Here's Qualcomm- http://www.anandtech.com/show/8933/snapdragon-810-performance-preview/4 http://www.anandtech.com/show/8933/snapdragon-810-performanc... Here's ARM- https://www.arm.com/products/processors/technologies/biglittleprocessing.php https://www.arm.com/products/processors/technologies/biglitt... They favor the little cores, unless the process actually saturates the core at which point it is elevated to a big core, because the power profile for low demand tasks is far better for the small cores. I'm going to favor the industry's interpretation of this a bit more than your anecdotal, occasional compiler-writer knowledge. what do you expect the A57's to be doing in this world? ...

DannyBee 11y ago

"The A53 cores will likely carry the vast majority of every day use, and redouble the battery savings." non-ARM-manufacturer citation needed :). My experience as a compiler guy (that makes the toolchains for these kinds of phones) has been that big little brings improvements to what these guys can shove on a chip and advertise, but so far not real improvements to battery life or real numbers. There reason why is pretty simple. In an ideal world, you don't want anything running at all. You don't want A53's "handling the majority of the workload". What you want is to wake up, do whatever work is needed as fast as possible, and go back to sleep. Period. Sleeping chips are lower power, by far, than idling chips. If it's faster to do that work with an A57, it'll generally give you better battery life to do that. Again, this is right now, based on perf per watt/blah blah blah. Maybe someday, in the future, a53's will be so low power vs a57 that doing something else makes sense. But it's not true now, AFAIK. Instead, they make big-little because they can't really increase the speed of the higher end cores more without increasing power usage too much.

inversionOf 11y ago
You don't want A53's "handling the majority of the workload". Yes. You do. If I'm casually browsing non-intensive web pages, e-reading, or watching a Netflix movie, or even encoding a video, the background is doing IO rate limited system updates and basic data logging, etc, the vast majority of the time the CPU demands are very low, but frequent enough that putting a CPU to sleep is completely out of the question. An A53 has a much lower ceiling, but a much better middle tier power usage level, than the A57. Yes, if you want to run a benchmark the A53 is not a good bet (and is generally worse in a workload power usage), but it is a very good bet for most real world usage.
- DannyBee 11y ago
  No, you don't. Encoding a video should not be CPU, so let's get that out of there. Most of the rest is more GPU dependent than CPU dependent. The amount of CPU time you should be spending on these tasks is really low. For example, web browsing and reading, the CPU should be asleep most of the time. Now, don't get me wrong, there are plenty of very silly little tasks for A53's to do, but what you listed are not those tasks. It's more things like "syncing" or something that is a poll loop and event bound, not something that is in any way CPU bound. Period. CPU bound stuff is not something for the A53's in this to tackle. It makes battery life worse. That is what the actual, in-the-field data says. " a much better middle tier power usage level, than the A57" Truthfully, for most A53 cores, this is true only in the dreams of the chip designers. "but it is a very good bet for most real world usage." Then what, pray tell, do you expect the A57's to be doing in this world? And why, in practice, has big.little and other things not shown any better battery life at all if it's really a better way of doing things. I have no doubt it may be a better way of doing things in the future, but it ain't right now ;)
  - inversionOf 11y ago
    The amount of CPU time you should be spending on these tasks is really low. Which is exactly the point. They are not CPU intensive, but the CPU is constantly doing a multitude of little things, whether simply moving memory around from the GPU to storage, sending the render buffers for the 60fps display, etc. Another comment mentioned, rightly, that cores are put to sleep in they don't have anything to do in a quantum. A quantum is an enormously huge period of time, and is a macro power management technique, and is the last bastion behind idle frequency scaling, and big.little. Truthfully, for most A53 cores, this is true only in the dreams of the chip designers. You have zero expertise to be saying this. I mean, here's how Samsung actually does it on a big/little setup- http://www.androidauthority.com/galaxy-s6-octa-core-processor-usage-617585/ http://www.androidauthority.com/galaxy-s6-octa-core-processo... Here's Qualcomm- http://www.anandtech.com/show/8933/snapdragon-810-performance-preview/4 http://www.anandtech.com/show/8933/snapdragon-810-performanc... Here's ARM- https://www.arm.com/products/processors/technologies/biglittleprocessing.php https://www.arm.com/products/processors/technologies/biglitt... They favor the little cores, unless the process actually saturates the core at which point it is elevated to a big core, because the power profile for low demand tasks is far better for the small cores. I'm going to favor the industry's interpretation of this a bit more than your anecdotal, occasional compiler-writer knowledge. what do you expect the A57's to be doing in this world? ...