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Factual 'Big Mac' Results
danigiri writes "Finally Varadarajan has put some hard facts on the speed of the VT 'Big Mac' G5 cluster. Undoubtedly after some weeks of tuning and optimization, the home-brewn supercluster is happily rolling around at 9.555 TFlops in LINPACK.
The revelations were made by the parallel computing voodoo master himself at the O'Reilly Mac OS X conference. It seems they are expecting and additional 10% speed boost after some more tweaking. Srinidhi received standing ovations from the audience.
Wired news is also running a cool news piece on it. Lots of juicy technical and cost details not revealed before. Myth dispelling redux: yes, VT paid full price, yes, it's running Mac OS X Jaguar (soon Panther), yes, errors in RAM are accounted for, Varadarajan was not an Apple fanboy in the least... read the articles for more booze."
It's highly dependent on the interconnects, the topology of the network, the software that does the clustering (i.e., that actually makes the nodes available for parallelized word), etc.
So minor tweaks can have major effects, and getting it tweaked properly is quite an accomplishment.
To those who are wondering why the G5 is a serious contender for supercomputing applications( and why VT decided the way they did ), you may want to follow this link: http://www.chaosmint.com/mac/vt-supercomputer/
Here's a quick rundown:
Dell - too expensive [one of the reasons for the project being so "hush hush" was that dell was exploring pricing options during bidding]
Sun (sparc) - required too many processors, also too expensive
IBM/AMD (opteron) - required twice the number of processors and was twice the price in the desired configuration; had no chassis available
HP (itanium) - same
Apple (IBM PPC970) - system available with chassis for lowest price
Here is da slide-show
This page was generated by a Barrel of Circus Midgets, and that is the way I like it!!!
Yes, that would be shocking if it had happend, but it didn't. VPI paid the normal educational institution quantity pricing for 1100 units. They did NOT pay the single-unit price.
Can we put this canard to rest now?
-jcr
The only title of honor that a tyrant can grant is "Enemy of the State."
Just FWIW, they are claiming power usage of 1.5MW for this cluster of 2200 processors. Cray just released the numbers for their upcoming Red Storm cluster with over 10,000 AMD Opteron processors, just slightly less than 2.0MW.
Ugh, this is getting old.
Red Storm, the machine by itself itself, uses 2.0MW.
Big Mac and all of its networking gear uses less than 0.75MW. The supercomputing center itself (building, air conditioning, UPS battery charging equipment, and the 1100 G5s) is fed by a 1.5MW substation feed. They're still not even maxing out the substation.
The latest, fastest Opterons (not the scaled down low-power Opteron for blade servers) consume 53 watts at full clock. PowerPC 970 @ 2 GHz consumes 48 watts. The U2 and K3 motherboard chipset on the dual G5s uses just as much power as the PowerPC 970 "G5" processors. Hell, the power supply in a dual processor G5 system is 550 watts. 550 x 1100 machines = 0.61MW.
I usually never reply to these things, but I think it is funny that people are arguing about how he ordered on the Apple Store. I find it even funnier that people would even go to the Apple Store and try. It was a joke! There were a lot of dedicated people at Apple, including myself, that helped to make this dream become a reality. The "myth" that I would like to clear up is that Apple DID have a clue and a lot of great people at Apple have been working really hard for that last few months, making a lot of personal sacrifices to make sure that all the awesome work from Dr. Varadarajan and the rest of the cluster team could be possible and successful. That's my 2 cents.
Jerome Holman
Apple Campus Representative @ VT
http://filebox.vt.edu/users/jeholman