Sorry, but I have to respectfully disagree with a lot of the things you've said.
As said, I'm no hardware expert, so I'm thankful for any information here
1) NEON is on every Cortex-A9 SoC out there except Tegra 2, which is itself outmoded even by nVidia. So you're right, an A9 SoC is not automatically better, but that only applies if you're dumb enough to use Tegra 2.
Well, I knew the Tegra 2 didn't use it, and according to the
ARM information page about the Cortex-A9 stating "Optional
NEON™ media and/or
floating point processing engine", I thought there were more SoCs that do not have NEON included, especially some in these cheap chinese devices that will probably keep flooding in.
2) NEON is integer SIMD, it's not an FPU. gpu_neon is 100% integer NEON.
Thanks for the correction
4) Benchmarks on mobiles are a real crap-shoot and frankly, most of them aren't very good. To get a good feel for what's best for something like Pandora you'd want to look at performance differences for a pretty particular set of programs, like emulators. I can think of good reasons why emulators could benefit noticably more from A9 than A8. For instance, dynarecs aren't generating code that's scheduled well, but OoOE on A9 helps hide that. And auto-prefetching goes a long way to help access patterns for software graphics rendering.
The benchmark wasn't done on a smartphone. I got this directly from an SoC manufacturer, who made a direct speed comparison of the A8 and A9 (at same CPU speed).
The blog post I linked to stated the same, so I'm pretty sure this is accurate.
This is just a stock CPU comparison though, not including any optional stuff.
5) No one's clocking Pandora at 1.2GHz while running NEON.. if I were you (and Craig) I'd be VERY careful about making these comments that allude to "you can just overclock to close the gap"
True, forgot about NEON here. That needs to be corrected.
6) Size of L2 cache does matter, but in that regard Pandora only has 256KB.. only the aforementioned cheap 65nm Amlogic SoC pairs a single Cortex-A9 with 128KB. Almost all the rest give 1MB shared between two cores. Memory bandwidth also matters, but more important than that is memory latency and OMAP3530 is on the poor end of that spectrum (some other SoCs are too though, it's hit or miss)
How much difference can there be, speedwise?
7) Saying that dual core only helps if YOU multitask is off the mark. A single program will benefit greatly if it's well threaded. Maybe most things running on Pandora now aren't, but this is gradually changing in the computing world at large. It can make a big difference for DS and PSP emulation for instance (see desmume, where the 3D rendering is threaded). Even N64 emulation as it is on Pandora would probably benefit a lot from two cores, because the second core could be used to soak up all the CPU time that the OpenGL ES 2 driver needs. And do you really think you sacrifice a lot of power consumption if you only end up with a small speedup? If you're not using the CPU cycles you're not going to be using a lot of power, it'll spend most of its time sleeping..
Yeah, I probably didn't make myself clear with the post.
Specwise, this COULD make a difference - but I was looking at it from a realistic view.
How realistic is it that many application actually make use of that?
N64 emulation would be faster anyway (I mentioned that above as well), but how realistic is it that somebody would port stuff like DS or PSP emulation working fullspeed on a Cortex-A9 right now?
Apps ARE slowly changing to make use both cores, but I'm not sure how fast this change will really happen (took ages on a PC).
8) While on power consumption, newer SoCs will offer better power consumption because they're on better (more modern) manufacturing processes. And because Cortex-A9 intrinsically has better perf/W than Cortex-A8. Even for DM3730, saying it's "the same chip" is disingenuous.. since it's a 45nm part, it WILL have better perf/W and it WILL clock higher. It also has double the L1 cache. Comparing a stock 1GHz to overclocked > 1GHz for Pandora is highly unfair. Maybe you should find what DM3730 overclocks to? And should you really ignore the higher memory bandwidth (try setting OMAP3530 to 200MHz memory clock and get back to me, notaz says he failed to) and nearly twice as fast GPU?
I've got a BeagleBoard-xM, and Ari also made a post about how he tried running N64 on the DM3730, didn't give a huge speedboost.
According to various posts I found on the internet, the DM3730 doesn't go higher than 1,2GHz when overclocking.
I'd love to do more tests on that myself, but that's what I found so far.
The BeagleBoard-xM doesn't feel faster for me than my Pandora does (running ArchLinux ARM on both as a test).
9) You don't mention GPU, but Pandora's is way behind. While we're on the topic of software, I'm actually with Craig in believing that Android support would bring a huge push. But that needs better hardware to be even remotely competitive with actual software performance.
As mentioned above: I'm seeing it in a realistic way, not pure technical (should've made myself more clear about that).
People even stated in this post that they didn't even use the GPU at all until now.
Why would they do that on an A9 suddenly?
I'm not sure others really do that. Every Android phone I tried (tried Samsung Galaxy S2 and the likes as well) felt somewhat sluggish.
I was looking for a new phone, so I tried various phones, but in the end, I bought a used N900 (had one already).
The only smartphone OS that doesn't seem laggish to me (at least in the UI) is the iPhone.
But that's probably because the OS is optimized to run on one single hardware with huge money behind it...
And still, Forget-Me-Not on an iPhone 4 needs more frameskip than it does on the Pandora.
The iPhone4 is also still using an Cortex-A8. Would anybody say the iPhone4 is outdated? (Well, it sure is, as the 4s is newer, but who would SAY that the iPhone4 is outdated?)
Are there any games that really NEED an iPhone4s and wouldn't work on an iPhone4?
10) Pandora could potentially be better at video playback, but only to a point, and the software situation is messy. With a lot of newer SoCs you get easy 1080p playback. Also features like HDMI out.
HDMI out is the only real thing missing here, not sure we need 1080p on an LCD
But yeah, if you're using it as a media player, it would be nice.
11) You can't really say current SoCs aren't really faster but A15 SoCs will be 8 times faster. If all you care about is single threaded performance (as the post seems to) and you're confident in Pandora being a lock at 800MHz then a Cortex-A15 will most certainly not give you 8 times over that.
True, with 800MHz, it won't be 8 times as fast.
Though I remember reading somewhere that the A15 will have about 4x the performance of the A9 with the same speed.
And as the A15 will start at 1,5 - 1,8GHz, it will have about 8x the performance compared to our A8 with 800MHz.
13) Even for tasks where you don't need more CPU time, better SoCs still offer better battery life and/or let you do more stuff in the background. But like everyone says, there's way more that can be done on these
things than N64 and PS1 emulation, including some things that always benefit from as much as you can throw at it.. like compilation.
True. But what WILL be realistically be done?
I'm sure the Pandora would be capable of running PS2-Like games, if there would be somebody who coded it.
I think we can agree we cannot expect big blockbuster commercial titles on the Pandora, so we'll most probably never see a game like that, but it would be possible.
So regardless of having an A8 or A9, we probably wouldn't see any other games.
About compilation: Yeah, that would be neat. Though I'm not sure how many users are actually compiling on their Pandora.
14) If you're telling me to run my Pandora at 800MHz that means I can change the voltage without voiding my warranty, right? Because at OPP3 my Pandora doesn't survive NEON code at 800MHz w/o freezing.
Sure, whatever the OS allows is within warranty.
OPP5 is within TIs specs, and that's the maximum the stock OS allows.
notaz is currently working on Kernel 3.2, which adds some OMAP stuff following TI's specifications.
The kernel forces OPP4 on >=550MHz, OPP5 on 600MHz.
You're right, Pandora does have things to offer that other devices don't, precisely because there are developers who are focusing on it more and because it's missing some software overheads (a compromise these other devices willingly make in order to bring in a vastly more meaningful app library). But that's all pretty tangential to the question of whether or not Pandora's userbase would benefit from something better or if Pandora is, as the title puts it, "outdated."
Well, I wanted to take a more realistic approach.
Is there ANYTHING you can do on a modern smartphone, that you can't do on the Pandora?
(not theoretically, but realistically).
Emulators like PS2 or GameCube are not possible at playable with an A9 (not sure if that would even be possible with an A15)
I haven't seen a game on iOS / Android that I think wouldn't be possible on the Pandora as well.
The OS itself on phones is needing a lot more CPU power (which makes sense, since it's a phone and should react to phone calls quickly), so some games (like Forget-Me-Not) even run slower on higher specced phones than on the Pandora.
So while the specs are outdated, the system itself isn't in my opinion.
That's what my approach of this was supposed to be.
The A9 is not the holy grail speed wise. The speed boost from the A9 to the A15 will be A LOT higher than from the A8 to the A9.
What I really want to know is less why better hardware is important and more why this post is important, especially since it reads eerily similar to one made by Craig on these forums ages ago.. Pandora is using an SoC that was first showing up in real devices in 2008. Are we really supposed to turn up our noses and say that 3.5 years of SoC advancement during a huge period of progress has nothing whatsoever to offer anyone?
Nope, as said, I am no speed whore.
I want to do a proper comparison in a realistical way, not theoretical way.
No app or game currently running on an A9 will probably NEED one. It would work fine on an A8 as well (might need some optimization, but should run).
So when is a hardware outdated? When new hardware is out, or when it's so slow it can't compete with current systems (not based on specs but on user experience)?
In the end, educate people of the facts.. then leave it at that. Let them make up their minds as to what is and isn't enough for their own purposes.
That's what I want to do
But as said, lacking a deep hardware background, I was just referring to what I got from talks with TI technicians, other sources and my own experiences.
I am planning some section on the new website which shows people who will just say "it's outdated" without taking a closer look why it ISN'T outdated.
So I'm trying to reach out into multiple directions:
* Is the A9 really that much faster?
* What is running on a smartphone that won't run on a Pandora?
I know you used to be in support of DM3730 in Pandoras, until it was evident that there were too many OMAP3530s purchased for that to happen any time soon. I don't think it's fair to only now act like that was never really worth consideration.
Don't be confused!
That was Michael saying that, not me. I'm still planning to use the DM3730 in future Pandoras.
Maybe I made myself a bit more clear what my goal was... not easy if English is not your native language.
