Reconfigurable Computers - Again? 51
shermNOTsherm writes "Here's a story on UniSci about research at the University of Rochester on reconfigurable computers. The idea is to dynamically adjust cache sizes on the fly to more efficiently operate. Supposedly halves power consumption, and is based on current commercial chips, not customized, so it's just a little closer to real world."
starbridge systems? (Score:1)
www.starbridgesystems.com [starbridgesystems.com]
I still ask myself if this if a legitimate company or a hoax...
Re:Sounds like a simple idea (Score:1)
It's easy(ish) to do on a per functional unit basis, but someone (in manchester?) has a whole chip designed that way. Impressive.
Don't know about energy consumption.
As for this chip, I was suprised that the cache was responisble for such a large part of the energy load. Isn't it possible to turn the cache off by software on some chips?
Johan
Re:PicoRadio and very low power consumption (Score:1)
Re:starbridge systems? (Score:1)
It is a company that claims to have some reconfigurable stuff for sale, but I've never seen any reliable references of anyone actually using anything by them... so I am dubious...
Re:Why adjust the hardware? (Score:1)
My Windows 98 machine (pII 400mhz, 128mb ram) boots in under 30 seconds from cold off (and that includes typing in 'windows' at the LILO prompt), why doesn't yours?
- Wedg
Software bloat (Score:3)
Re:Why adjust the hardware? (Score:1)
I also know of one major company who not only had this fault with *every* desktop, but were resolving every Netware name lookup via DNS prior to NDS. It took over 5 minutes to boot up Windows and log on to their network.
Been done before... (Score:1)
Re:Problems with reconfiguration (Score:1)
Re:Been done before... (Score:1)
http://www.starbridgesystems.com/
Outlook on the future (Score:1)
Even the samurai
have teddy bears,
and even the teddy bears
Startbridge systems has a commercial product! (Score:1)
Yes this has been done before and is nothing new! Star Bridge Systems has had a comercial product available for about 2 years now.
Here is a blurb from the technology section on their page
http://www.starbridgesystems.com/
Re:Why adjust the hardware? (Score:1)
Wow! (Score:1)
--
Re:Dynamic Reconfigurability and Noise (Score:2)
Actually, you don't want to set to zero unless it is already there - it's the act of causing a transition in a cell state which causes the noise.
Presumably, if you know that you're not using a bank of memory, you just turn off the power to that bank & let its contents dribble away through leakage w/o worrying about doing any DRAM refreshes on it.
Re:starbridge systems? (Score:1)
Re:Why adjust the hardware? (Score:2)
Generally, things go like this.
Manager: The customer has requested a new feature. Mr. Designer, can you come up with a plan.
Mr.Designer: (Thinks for three minutes) Well, we could modify module A, B and D and then write module L and T.
Manager: I'll put some people right on it.
There aren't enough engineers so a college grad is hired or someone is brought in from another project where they have been working in another language for several years.
Manager: I know you're new here, but we're in a crunch. You have two days to review our 11MB CVS code base, and the weekend to get the feature implemented.
Programmer: Sounds reasonable.
11pm on Sunday night.
Programmer: None of the stuff is coded right. None of it makes any sense. I'll just write the feature from scratch and hardcode some links into modules A and B.
The feature is written like it was a seperate program and shipped. The new guy writes his own library functions. A code optimizer is never run against it to see what's duplicated or if the 30MB of resources (mostly library icons the the Manager paid a lot to license) is ever used. No-one with an overall knowledge of how the whole code base works is ever kept around.
It doesn't matter though. The next new-hire will just continue the tradition.
Problems with reconfiguration (Score:4)
Having said that, I firmly believe that both this technology and Transmeta's 'codemorphing' ideas will become the norm within the next few years. Now, if only they could JIT Java bytecode in microcode...
Crusoe? (Score:2)
Despite they hype in this article it seems like they are making a lower power consumption chip by disabling extra transistors, lowering the cache size, and cutting the voltage... not exactly groundbreaking and i'm sure you'd be better using a SparcLite or ARM cpu if you wanted to achieve the same effect.
Dynamic cache resizing research @ Purdue (Score:2)
Just more power saving (Score:3)
As for the speed increase aspect of it, I doubt that this tech can turn L1 and L2 caches into each other - it probably can just cut the sizes of each - so leaving them all the way on all the time would give you them best performance - and of the power saving features would at best change nothing.
Sounds like a neat idea though, but the proof will be in the implementation .
Why adjust the hardware? (Score:4)
Lets face it; a lot of commercial software out there is bloatware of the finest. Recently I did a small test with some friends who also had a laptop; pentium 160Mhz, 64Mb internal memory, 4Gb harddisk, 12.x" LCD screen and running Windows 95. My laptop is a PIII 550Mhz, Win98, 6Gb hardisk and has a 14" TFT screen. Both were equiped with a PCMCIA network card. We put the laptops next to each other and booted the machines. The 95 machine was waay done while mine was just past the PCMCI initialization. And no; my machine does not have major programs which are loaded during boot; its a very plain Win98 installation, most commonly used for office applications and demonstration purposes.
Second example is something which most people experienced afaik; if you take win98 running on a PII266 Mhz and on a PIII500 Mhz you will notice some increase in performance but not as drastic as it could be. If you compare all these Windows based experiences with an environment as Linux, BeOS or OS/2 (I haven't played around with BSD myself) then you'll notice that by using environments like Windows you don't use the hardware to its full capabilities.
Offcourse I do realize that this isn't an issue in all cases. Not everyone uses Windows and in some environments the software is allready at the 'cutting edge' in which there is no more performance to gain by adjusting the software.
But if you focus on the consumers market then the remark "We'll have to rely on innovations like this to go faster" is not the issue.
Re:Problems with reconfiguration (Score:2)
Not too sure if this would make a big diference however.
Re:Sounds like a simple idea (Score:1)
Ummm if i am to correctly understand this this is what my Macintosh does on the fly depending on what i am doing both application wize, and to the power saving level i have specifieed, i do not know if this is accurate or not, but hey there is the little checkbox
.sig =
Dynamic Reconfigurability and Noise (Score:2)
I wonder how much of this happens already (sans the voltage lowering that would actually save power) in RAM chips in systems with tons of it. If a cell hasn't been used yet, it should be set to zero, and shouldn't be producing much if any noise). Unless refresh gets in the way.
RAM isn't usually a big problem power-consumption wise, but it should be possible to turn off bits of DRAM circuits that aren't in use. The chipset should be able to signal that automagically by looking at the page tables. In power-hungry devices, any savings should help (not to mention devices that currently have heatsinks on the RAM like RDRAM and the new nVidia card). Anybody have an idea on how much page table and processor state info modern chipsets keep around?
I wonder if there are any other devices that this can be applied to...
Re:This isn't new. (Score:2)
Because fast hardware is sexy. (Score:2)
Because it doesn't sell cars.
Seriously: when new cars come out, they try to sell you on the sexy things: how powerful the engine is, how fast it accelerates or handles, how luxurious the ride is, and if it's an SUV, how rugged you'll look when you drive it through old-growth pine forests - or, at least, while picking up the kids from band rehersal.
But in our rush to go faster and look better, the only time that automotive ads seriously push the economics issue is when a) they're trying to clear out old inventory and have slashed financing rates, or b) there's an energy crisis and they're selling low gas-consumption cars.
In the computer world, there's never an energy crisis, thanks to Moore's Law [tuxedo.org] (or whatever). Many people who are buying computers are buying far more power than they actually need, or are ever likely to use. The only people who are really worried about computational overhead are wonks like us - professionals. Lots of folks are willing to plunk down for a 700 GHz machine on which to check e-mail and browse Sports Illustrated [cnn.com] online.
Re:This isn't new. (Score:1)
PicoRadio and very low power consumption (Score:2)
These 'PicoNodes' are less than 1 cubic centimetre, weigh less than 100 grams (less than most cell phones), consume less than 100 microwatts (vs. 100 milliwatts for Bluetooth). They should even be able to scavenge energy from the environment, including vibrations from people walking by...
This project relies on reconfigurable hardware, amongst other techniques, for very low power consumption. More info, including the article, is available online at the project's home page, http://bwrc.eecs.berkeley.edu/Research/Pico_Radio
Re:starbridge systems? (Score:1)
=========================================
Star Bridge Systems' Hypercomputer systems amalgamate hundreds of FPGA chips into a generally-useful critical mass of computing resources with variable communications and memory topologies to form what the company believes is the first massively-parallel, reconfigurable, third-order programmable, ultra-tightly-coupled, fully linearly-scalable, evolvable, asymmetrical multiprocessor.
===========================================
I'm guessing that whomever wrote that won a "who can fit the most techno-jargon into one sentence" contest!
Re:Why adjust the hardware? (Score:1)
As it happens... (Score:1)
The Hotspot VM [sun.com] does something very similar to code morphing. Hotspot calls it "dynamic compiling," which is technically accurate (if you remember that "compile" can apply to bytecodes as easily as to source code) but not very sexy ("What? Another compiler?"). Calling the a simple code translation "morphing" is a little silly, but hey, that's marketing.
Ironically, Hotspot was invented at a company called Animorphic Systems (a reference to a language concept, not to mutant teenagers) before being bought out by Sun.
Re:Why adjust the hardware? (Score:1)
Debug it how? (Score:1)
I wish people who came up with novel ideas also developed methods to debug them. Can you imagine trying to find a bug in a CPU that is constantly changing its signal voltage, turning parts on and off, and speeding up and slowing down? Can you say "not reproducible"? Hardware has historically been more reliable than software in large part because it has been rigid. As hardware adapts the flexibility of software, it will also adapt other features of software: bugs and crashes.
Re:Why adjust the hardware? (Score:2)
In general, there's only one way in which you can improve processors: making them faster (well, and smaller and more power-saving, but smaller processors are usually faster anyway). So it makes sense for hardware designers to focus on speed. OTOH, software developers have a bunch of different, conflicting objectives (quantity of features, interoperability, extendability, user friendliness, etc), so it can be worthwhile to sacrifice some speed for those other criteria. Sure, we can complain about how bloated today's software is, but if it was faster, we would be complaining (more) about some other aspect of it. Software development is an exercise in compromise ...
Partitioned Cache (Score:1)
Re:Why adjust the hardware? (Score:1)
Why serialize progress (first software then hardware) when you can parallelize it ?
There is more they can do using FPGA (Score:1)
Another Project: The GIF Project (Score:1)
Usually, the FPGA is used exclusively by only one task on the host CPU simultaneously. But, the configuration and readback features of the FPGAs allows us to process several tasks in parallel on one FPGA. The parallel execution can be divided into a real parallel execution and a time multiplexed execution.
Read more... [uni-mannheim.de]
Is it (Score:1)
I will continue to write, if you have a spesific problem with the work, I can see about changing it. In the meantime, you can simply not read it...
And for anyone out there, here is a more representative excerpt
5:34:17.
The afternoon.
And gray rain clouds boiled overhead. She wished the rain would wash away the filth, but she knew that that wouldn't happen. It was ingrained in the place, to the core. And over the years that it had embedded itself it became vital to the place. The new structures were built on top of it, and the people had become like the rats that hid in the shadows, and they feed off it to.
She was eating a small package of the ambiguously trademarked 'Ice-cream, isn't it' (it was, technically). It was peach flavored, and as they rode she would dig into it with a small pink plastic spoon, and then place the spoon in her mouth. When the spoon was away from her, in the package, she could smell the decay here, the filth. The sweat and urine and shit and sex, and the forgotten rotting food in the brown brick apartment buildings, built long ago to maximize the population density.
And when the spoon was under her nose she could only smell peaches. She thought that peaches came from Georgia, but she wasn't quite sure (The one in North America, not Eastern Europe.). And she could see the rows and rows of green trees in green fields with yellow/orange peaches backdropped by the yellow/orange setting sun. She wasn't really sure that peaches even grew on trees though, and there probably weren't really any peaches in the Ice-cream, isn't it anyway.
Hashimoto was driving, and another agent, Myoki was in the back.
"So, why are we doing this during the day anyway?" Myoki asked, directing the question to Hashimoto.
"This place doesn't sleep." Hatori answered. And then added "It might even be more alive at night." She took another bite of Ice-cream, isn't it. "But the rain will keep them inside. That's why we waited until today."
"Plus, if he's like any computer-geek I've ever met he's probably going be awake most of the night anyway," Hashimoto said. Hatori smiled when she heard this and took another bite of Ice-cream isn't it.
Re:This isn't new. (Score:1)
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Re:starbridge systems? (Score:1)
The only reason we have integrated caches in processors is that the engineers have more transistors than they know what to do with. and memory is the easies thing to use them up with.
Re:PicoRadio and very low power consumption (Score:2)
Sounds like a simple idea (Score:2)
Scotty (Score:2)
JL
Re:Sounds like a simple idea (Score:2)
There are soft bios apps that change on the fly...
and I think that is the idea behind what transmeta and intel's new energy saving chips
Re:Problems with reconfiguration (Score:1)
thread rather than process; what you're trying to
cache is the working set of the execution thread (i.e. the portions of RAM that the thread is executing most often).
The problem with this would be expense (as you mentioned), and also that *current* processors are only faintly aware of the process and thread switching of the operating system. This would the processor to be aware of the concept of threads at a very low level indeed.
Very funky idea though
Using programming techniques in hardware? (Score:1)
I realize this is a change to *hardware*, but, to use programming terms, aren't they just going from:
int array[4095];
to:
malloc() / free()
The cache which is not currently malloc'ed can then be powered down.
Instructions? (Score:2)
See if I care.
I want my computer to be stable - this sounds like yet another source of hardware problems to me.
Re:Why adjust the hardware? (Score:2)
Sometimes the right thing to do *IS* to raise hardware expectations, rather than perfecting code. (for the sake of discussion, we'll set aside the issue of whether or not this cache hack is that much of an improvement.)
Writing better code isn't something a software company can just do on a whim. Some guy can't just brainstorm up the idea "Well, jeez, why don't we just rewrite this thing so it doesn't suck?" and have it happen overnight. Producing tight code takes time, and for most companies, it's best to have pretty good programs that work, and ship them out the door, than to write their word processor in hand-optimized assembly to try to make sure that the 1% of people in the world stuck with a 386 won't have to watch it grind slowly along. Say what you want about sticking to your ideals, but software companies have to have priorities.
Open source, community-contributed software projects do a really good job of this, because the developers aren't under time pressure, and they have the leisure to take however long it takes to get it right, and then release it.
The Mozilla project is a perfect example of this. They're taking Netscape, and rewriting it so it doesn't suck. It's smaller, faster, and is guaranteed to attract members of the appropriate sex, but... It's been how many years in the making, now? And even now, it's only 90% ready. It arguably works better at this point than Netscape did, but the project certainly isn't complete. By the time it's released, we're going to have a serious kick butt web browser.
If Netscape was using their developers to do this, and planning on releasing it when it was perfect, they simply wouldn't exist any more. Instead of making it perfect, they would have done the best they could, and shipped it out the door. Bigger and slower than it could have been, but at least they'd have something to offer.
In short, my point is that you optimize the software where it really counts - your kernel, the core of your apps - but at some point, EVEN for open source projects, there's a time when it's better to ship it out the door working, rather than taking forever.
Linux is still written in C.
--Kai
--slashsuckATvegaDOTfurDOTcom
This isn't new. (Score:4)
The only thing remotely new is that they are only disabling part of the cache at once, instead of the entire cache. Then again, that's probably enough for a patent these days...