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.
Correct, it could have been missing on any Cortex-A9 SoC, but it's only Tegra 2 (cheap ones from Chinese manufacturers like Amlogic and Rockchip have it). You barely save die space by not having it on a dual or especially single core SoC, it's really tiny.. at 40nm like Tegra 2 they probably saved at most 1-2mm^2 (whole chip is 49mm^2). I suspect that nVidia made this decision for marketing/strategic reasons, or were just completely mistaken somehow. Tegra 3 corrects this and adds NEON.
This makes a compelling argument for comparing against a Tegra 2, perhaps. But Tegra 2 is barely used in phones and is being phased out in tablets. OPT would be crazy to use a Tegra 2 in a device that's meant to be compatible with Pandora, so I'd rather take it off the table completely for this discussion.
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.
Vendors and various third parties are pretty bad at benchmarking too. In the former case companies can be especially misleading because they always have something to sell you (even TI knows you can buy OMAP3530 or DM3730 but not OMAP4s). It just varies way too much to make a broad statement, but I think any 10-20% figure is absorbing a lot of cases were the speed isn't improved much because things are dominated by memory performance or a somewhat atypical case where the scheduling on A8 is as good as it'll be on A9 and there aren't a lot of dynamic stalls. Highly optimized NEON code can actually run faster on A8 clock for clock. But I still wouldn't trade that vs an A9.
In the case listed you do have an A9 vs an A8, but it's a pretty high-end well done A8 implementation on 45nm vs a crappy 65nm budget A9. Samsung SoCs for instance have much better memory bandwidth than a lot of the competition, and in this case it has much more cache. So yes, you have to consider more than just the CPU core. But with
everything else equal A9 will often win a lot. Maybe that's the point you were really trying to get at.
How much difference can there be, speedwise?
Varies way too much per program to really make a statement, and I'm not aware of any tests on these platforms.. main memory performance makes a huge difference too (more cache helps more if your memory is slower). For some data points I'd look at current Celeron and Pentium vs higher end Intel chips that have more L3 cache.
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).
It's way more realistic that programs will benefit from multi-threading than that'll they use the DSP, or even make good use of NEON. In the end for something like Pandora you benefit a ton based on what a handful of programs do, not what everyone is doing on average. A few killer app that benefits from multiple cores is enough to justify it. I don't know about it helping DS or PSP emulation ports, but the best emulators on Pandora aren't just ports of PC emulators. So why should we use that standard when thinking of possibilities for new emulators?
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).
With all of the problems with say, Pandaboard's performance, I put little stock in these things being configured right. And a subjective test about how fast something "feels" isn't really that useful. It doesn't make any sense for DM3730 to not be faster, and TI wouldn't have added things to it if it did nothing.
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?
If Android were used that GPU would suddenly become much more relevant. That's the gateway, more than the CPU type. But even with the kind of Linux Pandora has if the GPU was better there might be more porting efforts. And assuming Pandora had better manufacturing capacity it'd sell more with better specs (and/or cheaper price..) and that'd attract more development. It's not really fair to say that no one cares about GPU when current circumstances and specs are holding back interest.
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...
UI response time is a software issue, but that doesn't mean that critical loops in games and emulators are going to all around run slower on these devices. The two things are pretty separate. You can't really compare how different UIs feel to judge hardware or other software quality.
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?
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.
Yes, I'm pretty sure people would actually say 4 is outdated compared to 4S. Of course, iPhone 4's hardware is better than Pandora's too.. I don't think games need 4, but it's kind of hard to bridge this with Pandora when a vast majority of phone games aren't available for it. With most games being PC ports it benefits from CPU more there. I don't know about Forget-Me-Not but most games available on the app store will have enough development effort to not end up behind a Pandora port in performance.
Yes, 1080p is actually nice to have when you also have good TV out.
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.
Take what you read with a little more scrutiny. You actually thought that an A15 could improve per-clock per-core performance over A9 4 times (and you think A9 is effectively zero faster than A8)? It'd be substantially faster per-clock than a Sandy Bridge. The real world performance improvement per-clock is going to be more like 1.5x. I would give Cortex-A9 a typical 1.2x improvement over Cortex-A8. Cortex-A15 in a Pandora like device might clock at 1.8GHz but it'd positively chew battery, still: (1.8 / 0.8) * 1.2 * 1.5 = 4.05x. A 1.2GHz Cortex-A9 that can be had today would give you about 1.8x, which is still substantial.
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.
The way I see it, the more you limit Pandora to its CURRENT niche the more you DO want CPU because you're doing more desktop-like things instead of phone-like things. But are you saying you're against Android, or..?
As for compilation, I don't know, how many Pandora owners are developers.. a lot? Maybe I'd compile on it if it were a lot faster
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.
So I guess the stance on that changed at some point. The changes sound good.
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.
Clock boosts are the biggest driver in performance right now. A9s are already out that can clock to 1.5GHz on tablets. I don't know what a Pandora can do; it's a lot bulkier and has a much bigger battery than a phone. But it's not a tablet.
hlide has said he believes in PSP emulation on a 1+GHz dual core A9 with NEON. I believe in DS emulation on similar hardware, or at least much better DS emulation than possible on Pandora. Not with ports of anything though. And I still don't really buy into the "OS is slower and makes your CPU effectively slower" mindset, I think the comparison is way more complex than that.
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)?
My biggest problem with your viewpoint is your black and white determination of if hardware is "needed" or not. If you want realistic, why not ask the users, are there times when they wish the Pandora was faster? Then it'd benefit from being faster. Maybe ask developers too. Limiting everything to PS2 and Gamecube emulation is way too narrow (and do you think an A15 SoC will suddenly have those emulators at "good enough"?) Forget DS and PSP, what about Saturn? Or less known platforms like PC-FX? What about web browsing.. flash, HTML5? What about boot up time? What about battery life? I don't really like these "everything is good enough and therefore can't be better" mindsets. But it's not like it's the first time we've had this argument so I'm just going to leave it at that.
And I don't like the bit about other phones being saddled by their OSes so therefore Pandora isn't outdated. It's not a phone, it doesn't have the app catalog, it's apples to apples. Pandora's hardware IS outdated because better hardware can be bought for the same price. That's a really critical evaluation point. It has been passed up by multiple design AND process revision stages (which are usually not done at the same time). I'd feel better if the question was instead "is Pandora's hardware good enough for your needs despite being outdated?"
I agree with you in a sense, though, that it's the specs that are outdated rather than the Pandora.. but that's more because the Pandora hasn't been updated nor replaced with any real competitor. I worry that lack of competition results in stagnation (but also opens up a lot of hurt for if a competitor really does drop down)
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.
MWeston said that you had to use up the OMAP3530s, but don't you agree with this? Still, in your opening thread you say the chip is the same. Why bother? Or is it just because OMAP3530 is eventually going to be EOLed? If it isn't already..