Two computers acting like one

[eggsrbad]

I was wondering if one could hook up two computers to act like one computer, like draw resources from both.

 

[Nodsu]

Since you are asking this question in this way.. The answer is no.

 

[Spike]

Hi Nodsu - Just a quick question if I may...

In a processing cluster, (I watched a TechTV video showing a Beowulf cluster), I seem to recall it said that the resultant processing power of the cluster was greater than the sum of its parts. This seems like a bit of an odd staement to me, and I'm not even sure if it was actually said. Could you tell me if this is actually true, and possibly offer a link to somewhere explaining why if it is? Is there some kind of set formula for the resulting power, or does it depend (as I would imagine) on various factors including OS and config?

 

[Nodsu]

Didn't see that show.. And that claim is a bit odd. It's them, who should come up with proof

I know that sometimes it is possible to get hyper-performance increase with multiple CPUs when the amount of cache across all the CPUs crosses some boundary. For example, your task may not fit into the cache of one CPU, but it will completely fit into the caches of two CPUs and you get way more than 2x the performance because the RAM latency is gone. Such occasions are very rare of course.

I suppose one can get similar effects with the combined RAM or disk space or the communications links of the cluster nodes.. A task may just not "fit" into a single cluster node as it "fits" into the cluster.

 

[Spike]

Just an aside, but while looking for the show segment (which I still can't find to watch - so if anybody can find it I'd be most obliged), I found this... PS2 Supercomputer

 

[DelJo63]

this is a multiprocessor topic. there are multiple forms of it;
Dual core cpus, give you X number of processors in one box.

• commonly shared memory
• access to all devices
• one network (unless there's extra NICs too)
• non-linear performance gain (eg 2x cpus < 2x performance)

SMP (Symmetrical Multi-Processor) -- the true name for the Intel marketing of Dual Core

Loosely coupled MP

• usually multiple boxes
• unique memory, devices, and networking
• frequently coupled together with a highspeed backplane
• almost linear performance gain

Clustered Processing -- the marketing name for Loosely coupled MP

google 'HP IBM Solaris hacmp' and there's a ton of reading available

 

[Spike]

Well, he did say "two computers" and so it is most certainly cluster processing we're talking about

Clustered Processing -- the marketing name for Loosely coupled MP

That really doesn't give the concept/subject the credit and description it deserves. Cluster processing is the basis of every SuperComputer in the world for one thing

In the case of that Beowulf cluster featured on TechTV, it apparently wasn't linear performance gain. (I really wish I could find that video again!) Processing clusters depending on setup can also have advantages and disadvantages over MP, not least the scalability factor.

I'm not saying that you're wrong about definitions, but rather that you may be understating it somewhat.

 

[DelJo63]

That really doesn't give the concept/subject the credit and description it deserves. Cluster processing is the basis of every SuperComputer in the world for one thing

which is why I cited
google 'HP IBM Solaris hacmp' and there's a ton of reading available

 

[eggsrbad]

processing cluster??

 

[DelJo63]

processing cluster??

yes, running processes in a clustered environment

btw: HACMP::- High Availability Cluster Multi-Processing
you may have seen a TV ad by Oracle on fail-safe processing clusters

 

[eggsrbad]

This is the first time I've ever heard of it, I'll look it up more and figure if i need to rephrase my question, are processing clusters generally better?

 

[Spike]

No problem Jo. I just thought to mention it so that those without the time to research it know what it's all about.

As for processing clusters being "better", better than what exactly? There are lots of factors to take into account.

If you are even thinking about setting one up, I should advise you now that what Nodsu said was said for very good reason. If you don't know what a processing cluster is, You're probably not of a sufficient ability level to set one up, let alone use it. That's not having a go at you or anything. It's just the way it is.

 

[eggsrbad]

yes just from hearing processing cluster, sounds technical, I was discouraged, but I would like to know more about them even if I can't use them they sound intresting. I'm thinking better as in faster but as I read more into it it dosn't seem very practical, like having a drag car as a daily driver. oh yeah and I'm not offended in anyway

 

[Spike]

Oh, That depends what you do with your computing and how indepth you want to go. For your average user, you're quite right. It's like using an F1 car to zip across to the local grocery store. It's quite practical really, but only where it's needed.

Me, I could use one - even if it's only for number-crunching (I have better uses, but I'll not confuse the issue. lol)

 

[eggsrbad]

I don't know if switching drag car to F1 was intentional but a F1 car would be much more practical than a drag car, straight lines and what not. Thats neither here nor there though. would it be good for say stuff like extreme multitasking, such as running one of the newest games while watching a movie and running a virus and seperate spyware scanner all at the same time.

 

[DelJo63]

for most of us without hugh grants of $$$, the SMP is an effective choice to
get the benefits of parallel processing.
best wishes.

 

[Spike]

would it be good for say stuff like extreme multitasking, such as running one of the newest games while watching a movie and running a virus and seperate spyware scanner all at the same time.

Maybe, but probaly not.

Current OS's used for processing clusters include only one real candidate from Windows, being Server 2003. OK, so that instantly rules out the lates game (and games aren't really written to be run in that environment anyway.)

Cluster processing is generally something that comes into it's own when doing vast computational tasks - like for example modelling the weather and projecting forecast models, or calculating pi to the 9*10^5000000 decimal places, crunching seti@home (or such) or generating enormous rainbow tables. That sorth of thing. To put it to use in watching a video while playing a game would simply mean that you'd wasted money on both the video and the game anyway, and should probably have simply just used the two computers seperately.

 

[eggsrbad]

awwwww man, oh well i was just throwing soething in the air but thats what i thought from the stuff i read i noticed that linux has lots o'stuff for clustering but I am not really linux savvy, nor do I do anything that would merit me to have one but still i would like to know mor about them they are intresting, probably wont ever look into them or use one for that matter but hey i would still like to know about them

 

[niceboy]

windows terminal services too should help u.

 

[LNCPapa]

Lots of universities have processing clusters and allow their students limited time to use them. It's not out of the question that you'd ever get to use one depending on what field of study you are in. The only problem is that what you do with this time if probably not something you'll really want to be doing anyway. Where I work we offer our students time on our cluster.

 

[DelJo63]

typical usage of clustered processing

from the BIG BLUE world (ie: IBM), MQ architecture.

Salient point: programs must be written specifically for the cluster environment.
Threads and HyperThread techniques are not sufficient. The major concepts
are Client/Server processing with Message Passing protcols.