Dual Core vs Single Core

[YankeeDudeL]

There's been some chatter in the Droid forum about the actual functionality a dual core will have in an Android phone, and we've certainly argued it here. I wanted to make a thread specific to this point as to the benefits in either direction and whether or not you're going to base your decision on your next phone based on it.

Now, let's push the envelope. NVIDIA is saying that they're going to have quad core in tablets by August and in phones by Christmas. Will Android be optimized for it? And more importantly, can you wait that long for a new phone?

 

[dyezak]

Having gone through this in computers we should all remember that just having a dual, quad, or 8 core processor means nothing if the software isn't designed to be multi-threaded and take advantage of the additional cores. Google has already said that Honeycomb is the only version of Android that will take advantage of multiple cores. So 2.2 (that is on the Bionic) may have some enhanced apps to take advantage of it, but until the OS is redesigned the intrensic benefits for the entire user experience will not be there.

 

[drdoom]

Having gone through this in computers we should all remember that just having a dual, quad, or 8 core processor means nothing if the software isn't designed to be multi-threaded and take advantage of the additional cores. Google has already said that Honeycomb is the only version of Android that will take advantage of multiple cores. So 2.2 (that is on the Bionic) may have some enhanced apps to take advantage of it, but until the OS is redesigned the intrensic benefits for the entire user experience will not be there.

Having had a quad core since '07, I can attest to this. I'm not sure how Android is coded, but even without multi-threaded programs, I could put my quad to use by setting different programs to different cores. Maybe Motorola did something to allow the currently opened app to run on one core while the other core manages all of the background tasks. It wouldn't be a very efficient use of the dual core, but it would be better than having one core idle and drawing power until 2.3 was available for download.
For the OP: I wouldn't even hold my breath on the quad cores. Look at how large the batteries in the Atrix and the Bionic are with these Tegra 2's. Not only would a quad core require more power, but it would also generate more heat. I haven't seen anyone complain about the Tegra 2's overheating yet, but it is definitely possible that a quad core in a mobile phone form factor could easily overheat. Also, just because Nvidia said that Tegra 3 would be available for tablets in August and smartphones in Q4 doesn't mean they will actually be used in the newest phones. Look how long ago Nvidia announced Tegra 2 and how long it took for phones and tablets to start using it.

TL;DR: Don't hold your breath because of the Nvidia Tegra 3 announcement.

 

[rushmore]

Tegra 2 is the real deal. My Gtablet makes my Incredible and Droid X in comparison seem like a G1. Really.

 

[YankeeDudeL]

Having had a quad core since '07, I can attest to this. I'm not sure how Android is coded, but even without multi-threaded programs, I could put my quad to use by setting different programs to different cores. Maybe Motorola did something to allow the currently opened app to run on one core while the other core manages all of the background tasks. It wouldn't be a very efficient use of the dual core, but it would be better than having one core idle and drawing power until 2.3 was available for download.
For the OP: I wouldn't even hold my breath on the quad cores. Look at how large the batteries in the Atrix and the Bionic are with these Tegra 2's. Not only would a quad core require more power, but it would also generate more heat. I haven't seen anyone complain about the Tegra 2's overheating yet, but it is definitely possible that a quad core in a mobile phone form factor could easily overheat. Also, just because Nvidia said that Tegra 3 would be available for tablets in August and smartphones in Q4 doesn't mean they will actually be used in the newest phones. Look how long ago Nvidia announced Tegra 2 and how long it took for phones and tablets to start using it.

TL;DR: Don't hold your breath because of the Nvidia Tegra 3 announcement.

In one of those videos (I think the first link), the guy talks about dual core not consuming nearly as much battery life b/c the tablet didn't have to work as hard to run the processess and therefore keeping it cooler.

I think a lot of us that don't have experience with this could use some info on this. I know I have a quad core pc, but I have no idea how it functions or it's benefits.

 

[drdoom]

Tegra 2 is the real deal. My Gtablet makes my Incredible and Droid X in comparison seem like a G1. Really.

That might have more to do with the architecture than the fact it is dual core. It could also have some optimizations to make it set different programs to different cores like I described in my other post.

In one of those videos (I think the first link), the guy talks about dual core not consuming nearly as much battery life b/c the tablet didn't have to work as hard to run the processess and therefore keeping it cooler.

I'm thinking the reason they have better battery life is that (I keep coming back to this next point ) instead of running all of these programs on a single core and having to keep it at 1Ghz in order to move things along smoothly, the programs are getting divided to the different cores and the cores are downclocking to say, 500Mhz each. It takes less power to run two cores at 500Mhz than it does to run one at 1Ghz, especially when they are manufactured on different processes (90nm vs 45nm for example). Once programs start getting optimized for dual cores, I wouldn't expect the better battery life to be as significant; it might even get worse if you start running a bunch of multi-threaded programs.

I'm just using my experiences with processors in the desktop world as a way to synthesize what might be happening in the near future with these dual core phones. I could be wrong and I would appreciate it if someone corrected any mistakes or incorrect assumptions I might be making.