Microsoft Please Read! Re:XScale optimization

[Rand]

Whew...
I feel like I've been going through a crash course on PC processors. I logged on this afternoon ready to add my (one) post to this incredibly long, interesting thread, but as I read where it's going now I'm troubled.

What I wanted to contribute was that today at the PocketPC Expo in Hollywood, CA, I sat in on the end of an Intel Keynote Speaker. At the end of the presentation I was first to ask my two questions. The first being, "As Intel shareholders, when can we expect to benefit from these devices..." The response had something to do with demand from the masses when these chips are combined with cell phones.

The second question I prefaced by stating that I understood very little about this issue execept for what I've been reading on this very BH thread. So I asked about the dissapointing lack of performance increase by the Xscale chip over SA. The response by this, apparently very knowledgeable Intel spokesperson was that Xscale is a new processor and new programs will be developed to take advantage of it. Also that there are currently undisclosed features that the Xscale will provide that are forthcoming. Also he stated that this is only the first Xscale and that future Xscale chips will be worth the switch.

OK, so my point of posting my naive, non-technical comments in this thread is that to me, the Intel statement made sense.

I think you'll find most typical users, (like myself?...) will agree.

In closing, why I'm troubled by the recent direction of this thread? To advocate interupting a marketing campaign of a new exciting hardware device to verbalize your (temporary?) frustration over this issue, seems like poor judgement.

Thanks for letting me add my $0.02 (Hopefully the sentiment of many of the silent readers of this thread...)

All the best.
Rand

[pixelator]

And I recall Apple telling //gs owners that they were buying the best home computer money could buy - and that it would have a long, comfortable life alongside the Macintosh.

Still, I do hope we see some hardware-talking apps that do take advantage of XScale and run faster on the PXA than on SA. So far, that hasn't happened yet.

b

[Bandung]

Well, not wanting to get sucked in by yet another Intel dance of the seven veils, the PXA26x line of XScale devices does look interesting. By putting 128 - 256 Megs of Flash on board with the processor, that hopefully will remove some of the slow memory read preformance issues. But it doesn't help anyone whose trying to pull down a big video file off of their micro drive.

There are lots of cute little gizmos within the current PXA250. Things like the ability to temporarily switch the processor into a turbo mode running at 1.5 or 2.3 x its 400 Mhz processor speed.

Yah, I know, you're probably asking "if this is the case, why haven't we seen performance gains". It turns out this feature was added in order to permit an application to temporarily bypass the PLL (Phase lock loop) which is used to down shift the clock and save power during low processing demands. It permits "instant" speed shifts, up or down.

The chip probably can't run in this state for long but then again, who knows, maybe it can? We were told that the XScale design objectives included processors capable of running at speeds up to 800 Mhz and more so maybe today's device just might have the genetic material to do so.

Still I would have thought that Intel has been at this pipeline cache game long enough for their design engineers to have learned something from previous processors. If so, then they should have gotten things right the first time with XScale. Maybe they need to buy Transmeta and so get farther up their experience curve?

[cideo]

Rand, I don't know what to say - so I am willing to say nothing at the meeting if being a PDA Yippie isn't going to help us. But the point of that idea was Intel introduced a new processor that built on the StrongArm and Microsoft walked away from it because according to Derek, "they are not ready for it." Since Microsoft doesn't manufacture these devices, they don't have the billion dollar investment OEMs do to keep them focused. So what happens if MS gets innocent people to buy into their tablets? What is to prevent MS from leaving everyone hanging again the second they get an even "better" product idea? Don't forget, XScale uses the architecture of the StrongArm adding a co-processor and some limited media instructions that no one seems to be using.

I am going to be able to get rid of my e740 so I am not going to take the XScale financial hit many others here will. I guess the point is do we sit by and let this all happen or do we try something else? It is clear that this thread didn't work very well.

Bandung you are an amazing guy. I recall you saying you were not in the industry in a post somewhere but I have to tell you I have never seen anyone with such a broad and impressive command of digital electronics. If you don't mind my asking, what is your background and where are you located? If you really are not part of the industry, can you recommend some reading for us? Like Rand, I am taken with some of the depth we have seen in this thread but I don't have the general knowledge to put all of the pieces together. I just know that my e740 seemed to work at half the speed of my iPaqs - and wasn't real happy about it. Thanks - I will abide by a majority opinion of the users on this thread.

[Bandung]

In a previous thread in which Derek participated, I commented on the need for Microsoft to learn from the Open Source community. To which Derek responded with how many focus groups and user encounter sessions his group has participated in.

Not to sound snooty but "encountering" and "focus groups" isn't what Open Source is all about. What Microsoft described is what we marketing types have used for as far back as I can remember. Somewhat more insightful was a conference shortly after that when Balmer talked about emulating the good aspects of the Open Source Community and by delivering more value.

Balmer shared how, unlike Netscape, the Open Source community is not going to run out of cash. "They started out bankrupt", in a sense, is what he said. So apart from letting a few valued developers/users, get access to Windows source code, the adventure stops there.

I'm not about doing Microsoft's job on this topic. They are going to have to research it and learn it themselves. After all, something for nothing is worth nothing. They need a way to better handle the forks in the road for those users who need more than the mainstream.

In the past, MS use to issue things like Power Toys. Pretty useful utilities that were not officially supported. Nevertheless, they worked and were very useful. But how many of these things has MS released in the past year?

So what's my point? Maybe they don't need to support two operating systems - SA and XScale. BUt surely, they can get some power toys out there that both users and apps builders can use to improve the XScale experience. I would like to encourage someone in one of those work stations to think outside of the box with regard to this XScale fiasco.

Even publishing technical papers regarding known deficiencies and/or strengths would be a great help. But this "silence '. It isn't golden.

I share pixelator's frustrations (but not to the same level of "out of pocket" experience . At the same time, a part of me wants to be the eternal optimist (aka the mythical 250 Mhz three headed Xscale creature that I invented)

Where there is the will, there always is a way.

[Bandung]

Gamma Ray,
I've been in Marketing and Business Development for quite some time. My forte is in taking technologies to market profitably. I'm the original Columbo around the techies. They in turn love to take this poor sod under their wing and teach him a few things or two. (It helps that I have a Masters degree in Quantum Optics and Semiconductor Physics - Deans Honor List but I don't tell them that.)

I started out in telecom and within 5 years was running the department responsible for the network expansion of all of data networks for the nation's largest carrier. Then I abruptly changed careers and went into marketing, finance, you name it.

In addition to my telecom background, I've worked for firms in the IT services sector as well as for Manufacturing. My current role? COO for a high tech firm. I may still get the facts wrong, use inappropriate analogies and not even understand fully what the techs are telling me at times. But I can sure as heck figure out what its going to mean to our bottom line. If it doesn't make sense to me, we ain't funding it.

And I love writing and teaching.

[cideo]

Well I am impressed! Are you operating in the USA or Bandung Malaysia (what is a good USA time to catch your new posts)?

At any rate, as Rand mentioned we have seen "Frontside Bus," "Video Bus," "Memory Move Function," "Emulation," "Pipeline" and other geekspeak here without anyone translating into English. PocketTV claims that their program doesn't use the OS to get the video to the screen but never explains how the OS normally works and how his program does the end run. Do PDivX and Media Player run the same way? I understand that the co-processor is especially useful for MPEG4 decoding but not MPEG1 - yet no one has ever explained why? I believe PTV says they can only use it for things like resizing. My general understanding is that the OS and available programs don't take advantage of the hardware. Because of this they run slower even though XScale uses the same basic instruction set with minor media embellishments and a co-processor (from the Intel site).

If you get some spare time it would be great if you could post your understanding of what is going on under the hood, especially with video in plain English. Include all the terms I have mentioned and anything else you can think of. Assuming that MS will never optimize, what raw processor speed do we have to get from Intel to actually improve performance over the StrongArm? XScale can go to 800MHz - is that what we need for quality video or is it only a matter of programmers writing an MPEG4 decoder that uses the co-processor on the 300MHz unit? I have seen a post here that said that a MS optimization in the OS could result in a 25%(?) speed increase. Why? If MS used the media extensions and co-processor on Player, would we be seeing 30 frames per second (fps) at appropriate bitrates to support the extra fps? If the other extreme techs here want to chime in that would be great - but remember you need to use plain English.

BTW - is this all happenning with MS because they want everyone to migrate to CE.net and their Tablet PC? I understand that CE.net is also available for the Casio BE-300. So here's another basic question. What is CE.cet? The next CE interface or OS? Thanks again.

[Bandung]

Wow,
Lots of questions. i suppose in time "the team" here at Brighthand can help with those answers.

First, an adjustment in one of my assumptions. I think the XScale's turbo mode doesn't actually clock the core at 1.5 or 2.3 x the 400 Mhz clock. Judging by the diagrams, it simply provides another path parallel to the PLL path which the core usually uses to get its clock.

So for example, if the PLL has geared down to 160 Mhz clock rate, the turbo mode simply provides the core with a clock rate that is 2.3 x this 160 Mhz for a period of time long enough to permit the PLL to shift gears and wind itself up to 400 Mhz again. (Something like that)

The easiest question to deal with first is the one about the MPEG4 co-processor. (ie the functions that ATI's Imageon 100 video chips perform) It performs some of the actual decoding functions in hardware, to offload the main CPU and allow it enough overhead to handle other tasks such as audio decoding.

Each compression standard uses different mathematical algorithms and processes with which to decode a file. Something hard wired in hardware for MPEG4 will not help with an MPEG1 decode. Its a cost vs flexibility tradeoff that one chooses if you use ASIC chips (Application Specific IC's) to do things rather than a programmable device like a cpu.

[cideo]

Bandung the math co-processor I am talking about is part of the XScale chip and is not specific to mpeg. As far as plain English, a better approach here might be something like "Phase Lock Loop (PLL)." Maybe even a short explaination for the technical newbies.

[imported_jeff]

Gamma Ray said:

BTW - is this all happenning with MS because they want everyone to migrate to CE.net and their Tablet PC? I understand that CE.net is also available for the Casio BE-300. So here's another basic question. What is CE.cet? The next CE interface or OS? Thanks again.

CE.Net is the next revision of their CE operating system. The way that they work it, their OS releases do have some interface stuff, but the users are free to do their own. They do this via the Platform Builder.

This is the case with PocketPC, which takes whatever CE release they have decided to use (with PPC and PPC2K, it's been CE 3), and add in their own interface, crafted to what they see as the requirements of the platform. Note that the PocketPC team takes CE, which is available for a large number of platforms/CPUs and makes the requirement that PPC is available only for ARM 4. The Pocket PC group then takes what they've got, and passes it to the OEMs as a toolkit so that they can customize for their own devices (not sure what the name of this product is, or exactly how it works).

Evidently the Casio BE-300 is another CE user, with their own interface requirements distinct from PocketPC. I would guess that they work directly with the CE platform builder, as they are not PPC.

Microsoft also supports a number of other mobile platforms, see the following:
Microsoft Mobile Developer Info