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Harvesting & Reusing Idle Computer Cycles
Posted by
Hemos
on Mon Jul 04, 2005 11:27 AM
from the making-good-use-of-time-and-resources dept.
from the making-good-use-of-time-and-resources dept.
Hustler writes "More on the University of Texas grid project's mission to integrate numerous, diverse resources into a comprehensive campus cyber-infrastructure for research and education. This article examines the idea of harvesting unused cycles from compute resources to provide this aggregate power for compute-intensive work."
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electricity (Score:5, Informative)
"wasted compute cycles" aren't free. I would assert they're not even "wasted".
Re:electricity (Score:3, Informative)
Re:electricity (Score:5, Insightful)
Parent
Re:electricity (Score:5, Interesting)
No doubt in the era of idle loops and HLT instructions unused processor capacity does yield benefits. However from the perspective of a large organization (such as a large corporation, or a large university), it is waste if they have thousands of very powerful CPUs distributed throughout their organization, yet they have to spend millions on mainframes to perform computational work.
Parent
Re:electricity (Score:3, Informative)
Electricity vs cost of more machines and labor (Score:5, Insightful)
This is a very insightful post, but has two crucial counterarguments
- Does anyone realize the cost of buying extra computers to handle peak computing loads?
- Does anyone realize the cost of idle high-tech, high-paid labor while they wait for something to run?
The proper decision would balance these three (and other factors) in defining a portfolio of computing assets that can cost-effectively handle both baseline and peak computing loads. Idle CPUs aren't free, but then neither are idle people or surplus (turned-off) machines.Parent
Re:Electricity vs cost of more machines and labor (Score:5, Funny)
"The proper decision would balance these three (and other factors) in defining a portfolio of computing assets that can cost-effectively handle both baseline and peak computing loads."
You're probably right, but oh what a beautiful line of marketing-speak... If you happen to work in management or sales somewhere, write this baby down!Parent
Re:Electricity vs cost of more machines and labor (Score:5, Insightful)
Personally, I ran the SETI@home client and the Golomb ruler client for a while, but stopped because of a variety of factors:
I think if grid computing is ever going to take off, it needs to become a capitalist enterprise. If someone would pay me a few bucks a day for my spare cycles, and the client was open-source, and there was close to zero hassle, I'd gladly do it. Remember, one of the good things about a free market is that it tends to be an efficient way to allocate resources.
Parent
Re:Electricity vs cost of more machines and labor (Score:5, Funny)
Parent
Re:electricity (Score:5, Insightful)
The next question is - who pays for the electricity then? University departments are notorious for sqabbling over who picks up the tab for a shared resource - and that's not even considering the wider inclusion of home users...
Parent
Re:electricity (Score:5, Insightful)
Yes, I do, the same for RAM being accessed and for a hard disk drive when it's seeking. But this is insignificant compared to the overhead of the power supply, fans, hard disk drive spindle motors, other circuitry that runs continuously, and dare I mention all those fancy-dancy computer case lights that are popular now.
The incremental cost of these otherwise-unused cycles is so low that they can be considered free.
So someone prove me wrong, what's the electricity cost of running a CPU at full cycles for a year vs. running at typical load? What's the cost of the lowered processor life due to running at a higher temperature. Chip makers will tell you this is a real cost, but practically, the machine is likely to be replaced with the next generation before the processor has a heat-related problem.
Regardless, the cost is MUCH lower, in both electricity and capital, than buying other machines specifically to do the work assigned to these 'free cycles'.
Parent
Wrong (Score:5, Insightful)
But case in point: My Athlon64 computer doubles its wallplug powerdraw (including everything:PSU, Mainboard, HD, ect) at 100% load compared to idle desktop (ok, cool%quite helps pushing idle power down).
The cpu IS the biggest chunck besides some high-end GPUs (and even those need MUCH less power when idle), and modern cpus need 3-4 times as much power under full load compared to idle.
Parent
Re:Wrong (Score:5, Funny)
I could probably do something fancier by monitoring power draw with it unplugged, but my balls would be fried before I could tabulate the accurate data.
Parent
laptop cores are much better (Score:5, Interesting)
0. all modern cores switch off idle things (like the FPU) and have done for some time.
1. those opteron cores have best in class performance
2. intel centrino cores, like the i740, have about double the specint/watt figure. That means they do their computation twice as efficiently.
In a datacentre, power and air conditioning costs are major operational expenses. If we can move to lower power cores there -and have adaptive aircon that cranks back the cooling when the system is idle, the power savings would be significant. of course, putting the datacentre somewhere cooler with cheap non-fossil-fueled electicity (like British Columbia) is also a good choice.
Parent
Re:Wrong (Score:3, Interesting)
Hrm no.
no need to repeat myself [slashdot.org]
Running cpus at full load has made a huge difference in the cost of operation since the early pentium days. His point is that the cost of the 'electricity' is less than the cost of buying/powering new hardware specifically designed to do the work. Remember the electrical cost of the systems that are idle doesn't go away. those systems are on, anyways. Computer lab access is generally 24 hours a day, so th
CPU power consumption (Score:5, Informative)
60-100W difference between idle and full power consumption. That is not an insignificant amount of power.
Parent
Re:CPU power consumption (Score:5, Insightful)
If you wanted to get that computing power in a stand alone system, you'd not only have to purchase the PC (up front capital), but you'd have to pay more for electricity. From the reference link, only about 30% of a computer's power is used by the CPU, the rest is doing nothin'. The computers referenced, at full bore use 185W (best case). That's $162 per year at my 10 cent per kilowatt hour quote. Cheaper, sure, but by the cost of a computer? Not even close.
Of course, there are other (hidden) costs involved in both methods, of which I'm not including in my (overly?) simplified model. And I'll just brush under the rug the fact that this kinda assumes that the average secretary has a top of the line system to surf the web with.
Parent
And the Pentium M?? (Score:3, Informative)
I've been buying AMD for about five years, but I think my next system will be a Pentium M. Just as soon as they're a bit cheaper...
--grendel drago
Re:electricity (Score:3, Interesting)
Since a watt is a watt, and for rough purposes you can either choose to ignore or treat power supply inefficiency as a constant, you can get an idea of what it costs.
Chip: 2.2Ghz Athlon 64
Idle: 117 watts
Max: 143 watts
difference: 25 watts
Kilowatt hour / 25 watts = 40 hours.
It takes 40 hours for a loaded chip to use a kilo
Re:electricity (Score:3, Informative)
Who pays for that extra electricity? What if the program was poorly written and destabilizes the computer?
Few to none of the distributed computing projects don't factor this in. It's a nice way of cost-shifting, I think.
I think it is a good way for an organization to make better use of their computers though, I really don't want any part of it.
Re:electricity (Score:5, Insightful)
This has political ramifications.
The goal: get a great, powerful, cluster of compute power.
You can't go to the administration and say, "We need to spend $150k on a compute cluster". The answer will be "we don't have one now, and everything's just fine. No."
So, you, being resourceful, implement this campus-wide cluster system that taps spare resources. Power bills go up a bit - nobody cares.
Now, a couple years later, lots of projects are using the cluster. But the thing isn't working well because the power's not there during normal peak usage.
At his point you go the administration, "we're losing tuition-paying students, and several grants are at risk because our compute cluster is not powerful enough. We need to spend $250k on a new compute cluster.
And THAT is how you manipulate your operations budget to augment your capital budget.
Parent
Re:electricity (Score:3, Funny)
You're Missing the Point (Score:5, Interesting)
Your choices are:
Note that the solution in this article is obviously not free due to electricity and other support costs, but it is undoubtedly cheaper than buying your own cluster and then paying for electricity and the support costs.
Parent
Re:electricity (Score:3, Interesting)
Re:Reused??? (Score:3, Informative)
You should have used your mod points and not made a fool of yourself.
An Athlon64 3400+ does not run at 3.4GHz but 2.2GHz. Thus you're whole calculation of computer cycles is wrong. 3400+ is a PR rating comparing the performance of the Athlon64 to a Pentium4 of 3.4GHz.
Re:Reused??? (Score:3, Informative)
But don't take it from me. From the horses mouth:
Section 2 The Model number
The model number is fairly straight forward the numeric code of the Core ID will give you the model number. In the case of the newer Athlon XP's it will be the PR rating of the CPU. Fo
Re:Reused??? (Score:3, Insightful)
Suffice to say however AMD calculates it's PR rating really doesn't change the fact that it's to provide a comparison between Athlons and P4. I can guarrantee you if intel released a P4 processor that changed that correlation, AMD would change their PR rating on new processor to match it. Of course now that Intel itself is going to a PR rating of so
Play fair on the resources (Score:4, Insightful)
Google's desktop search is one example where the timing and recovery back to the user is really done well.
__
Laugh daily funny adult videos [laughdaily.com]
GridMP is a commercial distributed computing impl. (Score:4, Interesting)
However, the most critical aspect of this type of system is not just that the application in question is just multithreaded, but that it be multithreaded based on the GridMP APIs. To do such would require either a significant rewrite of existing code or a rewrite of it from scratch. This is not a minor undertaking, by any means.
If the performance of the application and every cycle counts, then that investment is definitely worth it.
Heterogeneous Hardware & mathematical accuracy (Score:4, Interesting)
Heterogeneous Hardware - This is a major issue.
The kinds of things that interest high-end computing geeks tend to be extremely sensitive to round-off error.
If you're trying to get accurate results by spreading calculations around among disparate machines that might deploy e.g. IEEE 64-bit doubles, IEEE 96-bit doubles [Intel & AMD], IEEE 128-bit doubles [Sparc], or various hardware cheats [MMX, SSE, 3dNow, Altivec], then trying to make any sense of the results will drive you absolutely bonkers.
PS: A good place to start in understanding the uselessness of e.g. 64-bit doubles is Professor Kahan's site at UC-Berkeley [berkeley.edu]; you might want to glance at the following PDF files:
Parent
Re:Heterogeneous Hardware & mathematical accur (Score:3, Interesting)
That presentation was done in 1998.
That'd be seven years ago...
Ever heard of java.lang.StrictMath? Didn't think so. Been around since Java 1.3. Current version is 1.5.
Sure about that? (Score:4, Insightful)
REusing idle cycles? Really?
Spambots (Score:3, Funny)
"Compute" should only be used as a verb. (Score:3, Interesting)
GridEngine (Score:3, Interesting)
Free and opensource, runs on almost all operating systems.
Spyware, Adware & Malware (Score:5, Funny)
1st Grid Design: GNU Jet Fighter (Score:4, Interesting)
Could we really do this stunt? I see no reason why we could not. Dassault has done it.
Dassault, a French company, designed and tested its new Falcon 7X entirely in a virtual reality [economist.com]. The company did not create a physical prototype. Rather, the first build is destined for sale to the customer.
Re:1st Grid Design: GNU Jet Fighter (Score:4, Insightful)
Parent
Don't invent your own mouse trap (Score:5, Insightful)
PVM [ornl.gov] offers both the spec and the implementation, MPI [anl.gov] offers a newer spec with several solid implementations. But no, NIH-syndrom [wikipedia.org] prevails and another piece of half-baked software is born.
Where I work, the monstrosity uses Java RMI to pass the input data and computation results around -- encapsulated in XML, no less...
It is very hard to fight -- I did a comparision implementing the same task in PVM and in our own software. Depending on the weight of the individual computation being distributed, PVM was from 10 to 300% faster and used 5 times less bandwidth. Upper management saw the white paper...
Guess, what we continue to develop and push to our clients?
Re:Don't invent your own mouse trap (Score:3, Interesting)
Parallels to the ethanol debate (Score:3, Interesting)
How many cycles does it take to harvest the idle cycles?
Is the balance positive or negative?
Distributed computing less efficient (Score:3, Interesting)
Distributing computing processes to third parties is much more inefficient. The workload has to be distributed in smaller packets, it has to be confirmed & rechecked more often, and the same workload has to be done multiple times due to not everyone runs a dedicated machine or always has 'spare cpu cycles.'
I would agree that distributing the work load is cheaper in the long run, especially with an increase in the amount of participants, but it is not a 1 to 1 cycle comparison, and therefore it is not necessarily 'taht much cheaper', 'more efficient', or 'more prudent' for a research facility to rely on others for computing cycles.
Sorry. This is hardly news (Score:3, Interesting)
Wisconsin Condor (Score:4, Insightful)
Wow, I've never heard of this idea before... (Score:3, Funny)
Exciting to read a paper on this fanastic new idea.
How about extra GPU cycles? (Score:3, Interesting)
Wouldn't it be cool to utilize it to its full potential?
Even better, when the screen saver would normally in, just turn over the graphics card completely to the background process.
Imagine Seti@home running on your GPU.
PS: Ditto some other processors that aren't being used to their full capacity.
Re:How about extra GPU cycles? (Score:3, Funny)
GPU don't have real math... yet. So instead of Folding@home you get "tossed on the bed"@home. Which is unfortunately useless.
Stay tuned tho.
I am a sinner (Score:3, Interesting)
So what should I have done with that CPU power?
Re:If I could only use this to improve rendering t (Score:3, Informative)
Re:wear & tear associated with running at 100% (Score:3, Interesting)