Virginia Tech Supercomputer Cluster Info Session

[eddyg]

Re: Not running OSX

Originally posted by nilspace
They are not running OSX (any version). I've worked with the Admin who is running/working on the project. They have done a special build of Darwin (the open-source kernel under Aqua that runs OSX). They are hoping this does the trick. However, if it doesn't, they are already planning on falling back on Linux to run the cluster.

And how is "a special build of Darwin" not OS X. OS X is the entire package, including kernel, not just the GUI.

So if they are running Darwin, then they are running OS X.

Cheers, Edward.

 

[ryan]

Re: Re: Re: Expansion?

Originally posted by admford
Actually keeping all of the machines the same on a cluster helps out with programming. Since all machines are equally fast, you don't have to bother too much with the timing of data transfer to the server. When you have a cluster of different machines, programming becomes more problematic, and Virginia tech want to run atleast a basic benchmark to see the effective speed of the cluster.

I'm sorry but this is simply false. There is no real timing issues that have to be delt with in a situation like this. As each node completes its work unit it contacts the main server and basically says "Here are my resutls for work unit X, let me know when when you have another [work unit] ready for me." The server receives the completed work unit, places it in the completed/verify bin/queue and then hands out the next work unit to the waiting node.

 

[whooleytoo]

So many things in the article are striking:

- Apple the cheapest option (is this a first? ;-)
- Apple (using IBM chips) competing with IBM (using AMD's!)
- The G5 option requiring fewer processors than the Itanium or Opteron options!

 

[rundevilrun]

Originally posted by whooleytoo
You can? Isn't that... Deja Vu?

Deja Vu - Thousands of beautiful computers and three ugly ones...




For those who don't get it: Deja Vu is also the name a of chain of strip clubs whose slogan is "thousands of beautiful girls and three ugly ones"

 

[Kurt]

I wonder how long before some one else is building these multiprocessor computers using IBM blades with G5s.

 

[Wonder Boy]

WHA WHA WHAT?

I had to read that headline over 3 or 4 times. Apple is the cheapest option? Where am I? What year is this?

 

[network23]

"1,100 Dual G5's"

Man, what some people will do to make OS X run as fast as OS 9!

 

[Sun Baked]

Re: Re: Not running OSX

Originally posted by eddyg
And how is "a special build of Darwin" not OS X. OS X is the entire package, including kernel, not just the GUI.

So if they are running Darwin, then they are running OS X.

Cheers, Edward.

Apple markets Darwin and OS X as two different products and EULAs. While OS X has a copy of Darwin at it's core, Darwin is not equal to OS X.

While it does get people mixed up, it drives some people as crazy as the VERY old -- if Windows 1.0 has PC DOS at it's core, then if I'm running DOS I'm running Windows.

 

[AidenShaw]

never happen

Originally posted by Kurt
I wonder how long before some one else is building these multiprocessor computers using IBM blades with G5s.

You won't see that - IBM will call them PPC970 !!


Actually, the IBM BladeCenter would be a much cleaner solution.

You'd get 168 PPC970 CPUs in 6 square feet (one 19" rack), so 14 racks would hold more CPUs than the 1100 PowerMacs. The entire supercomputer could fit in a 10' by 10' cubicle!

You'd also have redundant power, remote management hardware, advanced ECC memory,....

The only big disadvantage would be that the blades don't have PCI slots, so no InfiniBand unless IBM makes an InfiniBand option. Each blade has dual GigE plus dual 2Gbps Fibre Channel.

 

[aethier]

Originally posted by network23
"1,100 Dual G5's"

Man, what some people will do to make OS X run as fast as OS 9!

lol

anyways that is going to be one major kick ass computer.

suddenly it doesnt seem as impressive to brag that my school has 6 emacs...
mind you that my school is only a highschool

aethier

 

[JoeRadar]

Re: Re: Not running OSX

Originally posted by eddyg
So if they are running Darwin, then they are running OS X.

I wonder what the full OS X has that Darwin doesn't that might be wanted in a compute farm?

I have always pictured compute/render farms as very simple OSes (e.g., stripped linux, no GUI, ...), perhaps with an efficient network stack. Load some custom code (e.g., folding code) on each box, send it some data, and give the code as much of the CPU as possible.

A full Windows XP or even OS X might be overkill for such a box, and may slow it down. Anyone have any direct experience?

 

[weez75]

Re: Re: Not running OSX

Originally posted by eddyg
And how is "a special build of Darwin" not OS X. OS X is the entire package, including kernel, not just the GUI.

So if they are running Darwin, then they are running OS X.

Cheers, Edward.

Darwin is not OSX. Darwin is an open-source operating system that is the foundation for OSX and its based upon BSD.

From Apple's Darwing page:
Q. How does Darwin relate to Mac OS X?

A. Darwin is the core of Mac OS X. All software built for Darwin should be able to run unmodified on Mac OS X. However, because Darwin by itself does not encompass all of the features of Mac OS X, software that depends on higher-level features of Mac OS X (such as the Cocoa and Carbon toolkits) will not run on a stand-alone Darwin system.

Check it out at http://developer.apple.com/darwin/projects/darwin/faq.html

So if the operating system for the VT supercomputer is Darwin then it is not necessarily OSX. If the cluster is running an early version of Panther as reported in several places then it is running OSX with Darwin at the core.

 

[Raid]

Originally posted by rundevilrun
Deja Vu - Thousands of beautiful computers and three ugly ones...




For those who don't get it: Deja Vu is also the name a of chain of strip clubs whose slogan is "thousands of beautiful girls and three ugly ones"

Hey rundevilrun you a local (in this case Toronto) ?

More on topic... I wonder if the computer array program pooch would be able to work with the new G5's and some older computers. I know it worked between G4's and G3's. It'd be interesting to see if three generations of Apple computers could be made into a functioning array. If it worked I'd keep my old computer and just hook it up to the array as a backgroup proccessor!

Raid

 

[Flowbee]

Re: WHA WHA WHAT?

Originally posted by Wonder Boy
I had to read that headline over 3 or 4 times. Apple is the cheapest option? Where am I? What year is this?

Yeah, forget about the speed. This has to be the best news Apple's P.R. department has had in a long time.

 

[JoeRadar]

Originally posted by whooleytoo
- Apple (using IBM chips) competing with IBM (using AMD's!)

IBM has a contract to build a supercomputer called ASCI Purple with 12,544 POWER5 chips (the, presumably, basis for Apple's next G5 (G6?) chip).

(CNET story, IBM press)

 

[Sun Baked]

Re: Re: Re: Not running OSX

Originally posted by weez75
So if the operating system for the VT supercomputer is Darwin then it is not necessarily OSX. If the cluster is running an early version of Panther as reported in several places then it is running OSX with Darwin at the core.

They could be running the Darwin 7 Preview Seed that corresponds to select portions of the 2003 WWDC Panther seed.

There may have been some updates in the seed that they needed.

 

[Tim Flynn]

Originally posted by Nermal
Hmm, I've got an icon called Déjà Vu in my System Prefs. It's part of Toast 6. With the amount of lawsuits going around these days, I sense another one coming along

Any comments on Toast 6?
I want to use it for two things, making SVCDs from iMovie (from a miniDV) and recording audio from the optical inputs (when I get my G5)

 

[dongmin]

Originally posted by iPC
More than half, from what I have heard. At best, this is just a nice excuse. It is good PR for Apple, but it is a lame way of trying to appease all those customers that ordered these machines when they were announced back in June. You would think Apple wants to keep the Mac faithful that buy the newest stuff happy...

Umm, it's not an excuse. Apple never said that your order's been delayed because of the VT cluster. All they said was that they're filling education orders first to time with the back to school season. (Of course it's not clear at all what they mean by edu orders.) The VT thing is just something sexy for us rumor folks to talk about. I don't think Apple itself has said a peep about the cluster yet.

 

[szark]

Originally posted by dongmin
The VT thing is just something sexy for us rumor folks to talk about. I don't think Apple itself has said a peep about the cluster yet.

Yes, they have. They linked to the CNET article on their "hot news" page, which is essentially a confirmation from Apple.

Although they certainly haven't said the cluster is the reason for the shipping delay.

 

[jettredmont]

Re: Expansion?

Originally posted by woodsey
Just a quick question...

When Apple releases dual 3Ghz G5s next August, can they simply be added to the cluster to increase the processing power, or do all the machines need to be the same?

Outsider guess:

Most likely they can just be added, but will not be fully utilized in a preferential manner. They'll work 50% faster than the other computers, and so will be pulling tasks 50% faster than the other computers around them, but won't end up getting "larger" tasks to keep the setup/execute ratio optimal unless the app in question "noticed" their relative speed.

This is based on a guess about how an individual application would structure itself, so might not apply in all cases.

IMHO, how well a faster machine would fit in would be a product of application design over system design.

 

[jadedchameleon]

Re: Re: Re: Re: Expansion?

Originally posted by ryan
I'm sorry but this is simply false. There is no real timing issues that have to be delt with in a situation like this. As each node completes its work unit it contacts the main server and basically says "Here are my resutls for work unit X, let me know when when you have another [work unit] ready for me." The server receives the completed work unit, places it in the completed/verify bin/queue and then hands out the next work unit to the waiting node.

Actually the original poster could be correct. I would guess some variant of MPI will be used in this, and MPI does NOT specify that you do workunit queuing. Simpler MPI programs simply divide the work into equal parts, and ship it off. Many problems depend on previous data, so the original poster was correct that timing issues (mostly inefficiency--the faster nodes are only utilized as much as the slower ones) can show up.

Considering the fact that many of these programs (this comes from working with a Top500--was around #100--cluster at a major university) are written by non-CS types--such as chemists, mechanical engineers and such, you can expect to see less-than-optimal programming.

 

[jettredmont]

Originally posted by mvc
Yup, but the part I found unlikely was that they would run with a beta at all.

Not explaining myself properly - been a long day

True enough. Although, by January 2004 (operational date of the system) I should hope Panther is no longer Beta.

 

[nilspace]

Re: Re: Re: Re: Not running OSX

Originally posted by Sun Baked
They could be running the Darwin 7 Preview Seed that corresponds to select portions of the 2003 WWDC Panther seed.

There may have been some updates in the seed that they needed.

I don't believe so. However, since Darwin is open-source, the Admin was able to tweak it and do a rebuild himself.

I'll try and find out more info and post it here.

 

[ffakr]

Re: Not running OSX

Originally posted by nilspace
They are not running OSX (any version). I've worked with the Admin who is running/working on the project. They have done a special build of Darwin (the open-source kernel under Aqua that runs OSX). They are hoping this does the trick. However, if it doesn't, they are already planning on falling back on Linux to run the cluster.

The Admin should explain to you that Darwin is not an open-source Kernel. Mach is the kernel in Darwin, which is an Open source OS, which is based off of FreeBSD, which makes up the core of Mac OS X.

Essentially (over simplified):
FreeBSD + Mach + Apple's Mods = Darwin
Darwin + Quartz + Aqua + OpenStep = OS X

 

[jettredmont]

Originally posted by ZildjianKX
Can someone tell me how exactly 1,100 Dual G5s being shipped to them was suppose to slow down the shipping for Dual G5s for everyone else? There were supposively over 100,000 G5s ordered, and supposively most of those were duals...

First, no one has officially given this as an excuse for delaying consumer shipments (although it is implied as such).

Second, there is a bit more involved at Apple fulfilling a large bid-contract order like this than in fulfilling 1100 separate G5 orders. I seriously doubt Apple just took 1100 G5's off the line, slapped themn in boxes, and called UPS (or FedEx). There is a huge ammount of support expected by large orderers, and generally given by any supplier (especially Apple).