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Brian d marge
14th December 2010, 19:44
Last question Honest guv !!:facepalm:

I run Openfoam, a CFD program

its a number crunching application ( big numbers and lots and lots of them )

I am running the solver now and it will take a few hours to complete on a duo core with 4 gig ram

Sooo..

I am building a new computer for this software

Ive been advised as rule of thumb , 2 gig of ram per CPU is about right

and the more CPU the better ...one assumes

Sooo

I thinks to me self ...Quad core ( I7 950 core bloomfield ) and as much ram as I can

4 gig stick x my four slots I have available ( they do 4 gig sticks of ram ? )

and a nvidia Geforce GT 430 video card ( 1 gig onboard memory )

all in a well ventilated chassis , has 5 fans incl a huge one on the top

and water cooled chip using the corsair H50 ( well its cheap !)

Can any one see any bottle necks , improvements ,,, or general any other stuff

bear in mind its a pure number cruncher ,,not a gaming rig


Kind Regards

Stephen

steve_t
14th December 2010, 20:00
Was looking at one of the Gigabyte X58 boards just out of interest and it can house up to 24gb of RAM!
SSD's probably aren't necessary but cooler and quieter... depends if your budget is unlimited :innocent:

Mental Trousers
14th December 2010, 20:02
Not quite what you're looking for, but for that sort of application I'd start looking at a small cluster, preferably of PS3's :D

May sound ridiculous but the PS3 is the number cruncher from hell and clustering a couple of things would make short work of OpenFoam.

Failing that a cluster of cheap bare bones systems that are basically cpu's, ram, motherboard and psu. Some 10G NIC's and away you go.

Sorry if that lot sounds stupid, but that's what I'd be aiming for.

steve_t
14th December 2010, 20:08
Not quite what you're looking for, but for that sort of application I'd start looking at a small cluster, preferably of PS3's :D

May sound ridiculous but the PS3 is the number cruncher from hell and clustering a couple of things would make short work of OpenFoam.


Are PS3's still a major force powering the Folding@Home project? That's a pretty sweet concept :yes:

Mental Trousers
14th December 2010, 20:24
nfi sorry. I haven't looked at Folding for a long time.

Brian d marge
14th December 2010, 20:36
ok

clustering? many cpu and motherboards

I fear this will take a bit of googling

24 gig of Ram......... I like

stephen

off to google

sil3nt
14th December 2010, 20:39
Do you have a budget? Those $1500 i7s are stupidly fast.

Gremlin
14th December 2010, 20:44
I haven't seen 4GB DDR3 dimms yet, but thats not to say they don't exist.

Most i7 boards should be coming with 6 slots for memory, making 12GB of memory. Not sure what your crunching does (not familiar with the software either) but disk IO perhaps?

If you're that worried, just get a ProLiant DL385 G7 or similar... spend a few grand taking her up over 100GB of memory, 12 core CPU (x2 of course)... you'll be done in a jiffy! :yes:

Brian d marge
14th December 2010, 20:49
Failing that a cluster of cheap bare bones systems that are basically cpu's, ram, motherboard and psu. Some 10G NIC's and away you go


Sooo


2 quad cores and lots and lots of ram 16 x 2 running as a cluster???

why can I see a divorce on the horizon

Stephen

Brian d marge
14th December 2010, 20:51
Do you have a budget? Those $1500 i7s are stupidly fast.

thats what I was looking at Lga 1366 Core I7 950 Bloomfield

quite reasonable price at local shop

Stephen

Brian d marge
14th December 2010, 20:54
I haven't seen 4GB DDR3 dimms yet, but thats not to say they don't exist.

Most i7 boards should be coming with 6 slots for memory, making 12GB of memory. Not sure what your crunching does (not familiar with the software either) but disk IO perhaps?

If you're that worried, just get a ProLiant DL385 G7 or similar... spend a few grand taking her up over 100GB of memory, 12 core CPU (x2 of course)... you'll be done in a jiffy! :yes:

I am filling out the divorce paper as we speak

Knees are going weak ...

seriously though, is it possible to run 2 quad cores ?

does everything have to be matched , ie the same on each motherbaord?? ram and videocard?


Stephen

SMOKEU
14th December 2010, 20:56
Buy a 1055T or a 1090T with an 890FX board. They OC to 4GHz on air and are great for multi threaded apps. I wouldn't go for an X58 setup unless you have lots of cash to burn.

Hook up a 6850 and you can OC it to close to 1GHz on the reference cooler.

steve_t
14th December 2010, 20:56
2 quad cores and lots and lots of ram 16 x 2 running as a cluster???

why can I see a divorce on the horizon

Stephen

Divorce? One for you and one fo the wife. How can she complain about that? :woohoo:

SMOKEU
14th December 2010, 20:57
I am filling out the divorce paper as we speak

Knees are going weak ...

seriously though, is it possible to run 2 quad cores ?

does everything have to be matched , ie the same on each motherbaord?? ram and videocard?


Stephen

Dual core processors are old. Get a single 6 core!

sil3nt
14th December 2010, 20:58
thats what I was looking at Lga 1366 Core I7 950 Bloomfield

quite reasonable price at local shop

Stephen$400? You can get a Phenom II 1090 with 6 cores for less. The I7 950 may still be better though it depends on how the application utilises the cores.

Just get the best I7 you can afford.

SMOKEU
14th December 2010, 21:01
$400? You can get a Phenom II 1090 with 6 cores for less. The I7 950 may still be better though it depends on how the application utilises the cores.

Just get the best I7 you can afford.

With a good board the 1055T will OC just as well on air as a 1090T so might as well go for the cheaper option. X58 rigs are expensive to build, just look at the price of a decent board and RAM. For gaming the 950 is better, but the extra cost isn't really worth it unless you're going for a big budget build.

Mental Trousers
14th December 2010, 21:04
seriously though, is it possible to run 2 quad cores ?

You can buy motherboards that run 2x quad cores no problem. They also take a shit load of ram. However, once you're looking at that sort of hardware you're giving her the entire house in the divorce and you get the basket the dog sleeps in.

SMOKEU
14th December 2010, 21:07
You can buy motherboards that run 2x quad cores no problem. They also take a shit load of ram. However, once you're looking at that sort of hardware you're giving her the entire house in the divorce and you get the basket the dog sleeps in.

Keep in mind you can't run 2 Bloomfields or Gulftowns on the same board.

steve_t
14th December 2010, 21:12
If you're giving the wife the house, grab some 8-core Xeon processors and ECC RAM. Server grade hardware will see ya right :drinkup:

Oops, Xeon MP X7560 processor is $6800 on pricespy though not available

Brian d marge
14th December 2010, 21:13
You can buy motherboards that run 2x quad cores no problem. They also take a shit load of ram. However, once you're looking at that sort of hardware you're giving her the entire house in the divorce and you get the basket the dog sleeps in.
I never knew you had met my wife

and the dog sleeps in a run outside ...I have a workshop with underfloor heating :woohoo:

so its all about the chip then , and floating point calculations

Here is what Open foam does

From my home page

http://477-racing.webs.com/apps/videos/


Stephen

sil3nt
14th December 2010, 21:17
Don't suppose you know how multiple cores affect the application? Tried googling but all i found was a thread about someone wanting to upgrade their CPU to an i7 because their calculation took a week....

If you have a spare couple of grand to waste go nuts with i7 and lots of RAM. And an SSD of course!

SMOKEU
14th December 2010, 21:20
Don't suppose you know how multiple cores affect the application? Tried googling but all i found was a thread about someone wanting to upgrade there CPU to an i7 because their calculation took a week....

If you have a spare couple of grand to waste go nuts with i7 and lots of RAM. And an SSD of course!

Few consumer level apps can make full use of 6 cores. Most don't even make proper use of more than 2 cores. The exceptions are video encoding and CAD apps which will chew as many cores as you can feed them. Many of the newer games are designed to run on 4 cores.

Brian d marge
14th December 2010, 21:20
Don't suppose you know how multiple cores affect the application? Tried googling but all i found was a thread about someone wanting to upgrade there CPU to an i7 because their calculation took a week....

If you have a spare couple of grand to waste go nuts with i7 and lots of RAM. And an SSD of course!

I have to do a bit more research first but I think its the chip and ram that need to be man enough

Stephen

Thanks all

p.dath
14th December 2010, 21:25
Is the application GPU aware?

A quard core GPU will eat a quad core CPU on most mathematical operations performed on data sets.

Check out the CUDA standard.
http://www.nvidia.com/object/what_is_cuda_new.html

Brian d marge
14th December 2010, 21:27
Few consumer level apps can make full use of 6 cores. Most don't even make proper use of more than 2 cores. The exceptions are video encoding and CAD apps which will chew as many cores as you can feed them. Many of the newer games are designed to run on 4 cores.
Openfoam

The calculations I did used a course mesh, the finer the mesh ,,,,the more ommph you need and the better the results , me thinks

the lynfield chip is 20 000 yen , so quite affordable ( esp if I stop drinking ) and 2 x 4 gig of ram was 9000 yen

so 2 x lynfield chips and 2x2x4 gig of ram is 60 000 yen odd thats survivable ( a week or two of her not speaking to me ...kinda a christmas bonus )


Just a thought

Stephen

Brian d marge
14th December 2010, 21:29
Is the application GPU aware?

A quard core GPU will eat a quad core CPU on most mathematical operations performed on data sets.

Check out the CUDA standard.
http://www.nvidia.com/object/what_is_cuda_new.html

no idea but will ask

ta

Stephen

SMOKEU
14th December 2010, 21:31
Too much RAM can also be a bad thing. It's important to have a look at the latency as well. Cheap RAM can severely limit processor OC potential, especially with a locked multiplier.

Latte
14th December 2010, 21:48
If you're getting divorced anyway, do it in style and buy big iron. There'd be no house left to fight over :D

Madmax
14th December 2010, 22:14
Will Foam use Tesla tech
http://www.computerlounge.co.nz/components/componentview.asp?partid=13854

motor_mayhem
14th December 2010, 22:35
This may be a long shot but did you consider cloud computing?

Upload your data to the internet and let someone else's super ridiculously high spec'd machine do the work for you? Not completely sure but I gather you say "I want x no of cores at x speed for for x amount of time" and they just serve it up.


Alternately sift your way into NIWA, I bet their Cray would bang through your calculations pretty quick.

jeffs
14th December 2010, 23:25
Why make it yourself. All you need is money :)

http://www.oracle.com/us/products/servers-storage/servers/x86/sun-fire-x4800-server-077287.html

Brian d marge
15th December 2010, 00:13
Btw I did forget to say

I use linux 64 bit debian and I feel like its going to be , the I7 quad for a start , then followed by another of the same as the prices will have dropped by then

That ( While a long way of , ) will be enough to keep me happy till end of next year

and lots and lots of Rams

Canterbury one of course

Stephen

Grasshopperus
15th December 2010, 13:11
Before you go off and start looking at any hardware you should work to understand the problem.

Some equations do not benefit from more execution cores, for example; the Fibonacci sequence involves starting a sequence with a "0,1" and then figuring out each subsequent number as a sum of the two previous numbers eg. Fn = F(n-1) + F(n-2). In this situation you have to complete an addition before moving onto the next number, you can't start in an arbitrary location so the second core wouldn't be able to help at all.

For memory, are you actually maxing it out at the moment? Most calculations are CPU intensive as opposed to RAM intensive.

As for using a PS3, if your equation deals with floating point numbers, matrices or other types of data that can be optimized for "Single Instruction Multiple Data" instructions then they can be useful. But they're not the supercomputers in a box solution that popular media makes them out to be.

I've no idea what type of calculation you're doing but justly blindly spending money and hoping it'll make your problems go away could be a bit of waste.

Gremlin
15th December 2010, 13:17
It'll be damn fun doing it tho, until you see the invoice. :D

p.dath
15th December 2010, 13:32
Before you go off and start looking at any hardware you should work to understand the problem.

Some equations do not benefit from more execution cores, for example; the Fibonacci sequence involves starting a sequence with a "0,1" and then figuring out each subsequent number as a sum of the two previous numbers eg. Fn = F(n-1) + F(n-2). In this situation you have to complete an addition before moving onto the next number, you can't start in an arbitrary location so the second core wouldn't be able to help at all.

May I prefer you to the Intel parallel processing language Cilk, and this document describing how to calculate the Fibonacci sequence using parallel programming.
http://supertech.csail.mit.edu/cilk/manual-5.4.6.pdf

Often it is a matter of thinking differently to be able to work in parallel.

Brian d marge
15th December 2010, 13:43
At the moment it looks like a "render farm" I was thinking about it last night ,

Custom made chassis ( cant be any harder than motorbike bits) then mother boards and chips and 2 gig per core

Thats quite cheap , infact I could build each node for less than 10 000 yen ( expanding as I get better

The master computer , will be the bloomfield chip with as much ram as it will take

I need to research this a lot more but thanks to u lot a few more avenues appeared
ta!

Stephen

Juzz976
15th December 2010, 14:03
Whats with the obsession with having all this RAM, do you people even look at how much is actually being used.

2GB per core, wtf thats retarded. So glad I'm not in the IT industry anymore, been taken over by over excitable numpties.

As you were:facepalm:

Latte
15th December 2010, 14:13
Some modern apps are very resource inefficient , I struggle with 2gb physical at work (VMWare console, 2 .net apps and a java app and it's all over).

Brian d marge
15th December 2010, 14:15
Whats with the obsession with having all this RAM, do you people even look at how much is actually being used.

2GB per core, wtf thats retarded. So glad I'm not in the IT industry anymore, been taken over by over excitable numpties.

As you were:facepalm:

I know how you feel

I have to listen to you when you bring your bike in for a service ,,,,

I was advised by someone I trust that around 2 gig per core is about right for Openfoam

soo,,,,, Im going with this ,,,

Dont feel bad if I put music on when your explaining about your pride and joy ,,,

Stephen

oh ps , why is it retarded in your Humble opinion

PPs , yes from memory over (70 % ,,, I have this wonderful system monitor in the tray , both cores near 90% ,,,,,Im running another solver in a few min

would sir like a screen shot??

Mental Trousers
15th December 2010, 14:30
Here is what Open foam does

From my home page

http://477-racing.webs.com/apps/videos/


Don't show me that!!!! Now I want to install OpenFoam and model the intake and exhaust on my race bike :facepalm:

Grasshopperus
15th December 2010, 14:32
May I prefer you to the Intel parallel processing language Cilk, and this document describing how to calculate the Fibonacci sequence using parallel programming.
http://supertech.csail.mit.edu/cilk/manual-5.4.6.pdf

Often it is a matter of thinking differently to be able to work in parallel.

Ha, got you you bastard :)

That example is just a lightweight demonstration of CLIK's message passing interface.

From the doco,
"In the Fibonacci example, a sync statement is required before the statement return (x+y), to avoid the anomaly that would occur if x and y were summed before each had been computed."

So this is simply making a parallel cluster work in a serial fashion by farming out each sequence number calculation to the cluster, getting the response and then farming out a request for the next number. In this case the network overhead for the sync would defeat the point. There is no true parallel processing here.

Brian d marge
15th December 2010, 14:40
Don't show me that!!!! Now I want to install OpenFoam and model the intake and exhaust on my race bike :facepalm:

its free at CAElinux

Meshing is the hard part.. but if you keep it simple and get a water tight , non manifold part it will run soothly

and yes , that what I do ,,,,,

( my next project is flow through an suspension mid valve , ,,,,tested by using shapeways 3d printer ............:innocent:)

Stephen

p.dath
15th December 2010, 15:24
Whats with the obsession with having all this RAM, do you people even look at how much is actually being used.

He is probably working with decent size data sets, and holding the entire data set in RAM makes the processing much faster.


Ha, got you you bastard :)...There is no true parallel processing here.

Doh!

p.dath
15th December 2010, 15:25
Have you considered simply renting cloud resource, like from Amazon and the like? You can pay by the hour of CPU time used.

Brian d marge
15th December 2010, 15:45
running a simple routine ( or whatever you call it now )

course grid, a few million cells and its

CPU 1 100% Cpu2 40 % Ram Just short of one Gig ( 800 ) and will be complete in 40 min ( and produce 5 gig of data)

All this will give is a rough idea of airflow over a VW beetle ( no reason)

and when I use parafoam to view the results , ( another area thats intensive ) every pass on the above data set takes ( up to ) 2 seconds per iteration ( this one has 1000 iterations )

So there u have it


Stephen

Beowulf cluster>>>???

Gremlin
16th December 2010, 01:22
Thank goodness memory is cheap. I was constantly running out of memory on my work PC at 4GB. Doubled it, and now its a lot more useful. Home machine runs on 12GB, always enough there. When using stuff like SQL, server 2008 and virtualisation, memory is measured in GB. A new application for a client is demanding 16GB of memory ish, multiple CPU, fast disks etc. Horses for courses.

I have a server 03 machine that is quite happy on 200mb of memory, yet I can make firefox use 1GB.

Brian d marge
18th December 2010, 22:48
ok have made a few prelim sketches , looks like 4 motherboards in a custom perspecs chassis with duo core chips , and 2 gig ram per board

the master will be quad core with 16 gig ram and a nividia graphics card .. cant remember its name

And customer paid up so money in ban ,,,all good

bring on my xmas holiday

Stephen

Brian d marge
18th December 2010, 22:49
ok have made a few prelim sketches , looks like 4 motherboards in a custom perspex chassis with duo core chips , and 2 gig ram per board

the master will be quad core with 16 gig ram and a nividia graphics card .. cant remember its name

And customer paid up so money in ban ,,,all good

bring on my xmas holiday

Stephen

steve_t
18th December 2010, 23:37
Make sure your perspex case has excellent air flow :yes:

Brian d marge
19th December 2010, 00:49
I will model the air flow on a CFD software

get it flowin over the chip

Stephen

Brian d marge
19th December 2010, 01:02
I will model the air flow on a CFD software

get it flowing over the chip

Stephen

Grasshopperus
19th December 2010, 10:23
Make sure the new perspex case has plenty of LED lights, dragon-shaped cutouts and spokey dokeys

steve_t
19th December 2010, 10:24
Make sure the new perspex case has plenty of LED lights, dragon-shaped cutouts and spokey dokeys

Spokey dokeys! You're showing your age Grasshopperus :drinkup:

steve_t
19th December 2010, 10:28
I will model the air flow on a CFD software

get it flowing over the chip

Stephen

Not sure what the current thinking is but a while back, I remember reading that a negative pressure case was preferred to better prevent areas of stagnant air. So, more exit air flow than input air. It'll be interesting to see what the software finds to be optimal

bogan
19th December 2010, 10:32
Not sure what the current thinking is but a while back, I remember reading that a negative pressure case was preferred to better prevent areas of stagnant air. So, more exit air flow than input air. It'll be interesting to see what the software finds to be optimal

easier to control dust build-up in a positive pressure case though, 3 years without cleaning my case and all the boards still look brand new, and all heatsinks still functioning properly :D

steve_t
19th December 2010, 10:38
easier to control dust build-up in a positive pressure case though, 3 years without cleaning my case and all the boards still look brand new, and all heatsinks still functioning properly :D

Yeah, true. If the case has heaps of small vents (which many do) and you have negative pressure, dust will get sucked in through those and clog shit up. The fans pushing air into the case should ideally be filtered too. Good case air flow won't mean dick if all the heatsinks and fans are jammed up with dust.

bogan
19th December 2010, 10:42
Yeah, true. If the case has heaps of small vents (which many do) and you have negative pressure, dust will get sucked in through those and clog shit up. The fans pushing air into the case should ideally be filtered too. Good case air flow won't mean dick if all the heatsinks and fans are jammed up with dust.

yup, I found a pod filter works well, and if you hack the back off it and make it kinda square, you can fit it plus a fan in 3 5.25in drive bays :woohoo:filter needs cleaning every now and then but you can remove the whole assembly same as you would a dvd drive and blow it out with a compressor, no chance of damaging components this way either.

Brian d marge
19th December 2010, 22:19
This is good

I had sketches now I need to review , as a case positive pressure will tend not to have dust but will need a filter

K& n anyone


Stephen

may have time tomorrow but for now . its all u can eat and drink for 60 bucks

bye must dash toodle pip

its a gonna hurt tomorrow !!!:facepalm:

SMOKEU
27th December 2010, 23:38
This is good

I had sketches now I need to review , as a case positive pressure will tend not to have dust but will need a filter

K& n anyone


Stephen

may have time tomorrow but for now . its all u can eat and drink for 60 bucks

bye must dash toodle pip

its a gonna hurt tomorrow !!!:facepalm:

Run a vacuum cleaner in the computer room at least once a week and clean the computer out once a year and you'll be sweet.

Brian d marge
27th December 2010, 23:43
Run a vacuum cleaner in the computer room at least once a week and clean the computer out once a year and you'll be sweet.
I need a woman for that

Stephen

SMOKEU
28th December 2010, 09:49
I need a woman for that

Stephen

There are plenty of nice Japanese girls for that.