V5 on multi-processors

Peter Lovelock

V5 on multi-processors

Hi All

I am nearly getting round to buying a new workstation again and was wondering if V5 had got any better at utilising multiple processors. I had a dual-cpu workstation some years ago and apart from a small part of the analysis package and the rendering package Catia never used the second processor (I'd have been better off spending the money on more ram). Since then I have always specified the fastest single processor machine that I could get, but multi-processor machines are becoming more common so I was wondering if V5 was now able to take better advantage of more than one processor. I'd also be using it in 64-bit if it makes any difference.

Does anyone have any experience with this?

Thanks

Pete

 

Jim Strawn

RE: V5 on multi-processors
(in response to Peter Lovelock)
CATIA still does not utilize the other processor other than the mentioned workbenches (and DMU Navigator for Tesselation). But, if you are using a PLM product, and MS Outlook, etc, you will see some performance gain in that these applications will run on the alternate processor.

Eduardo Magnetto

RE: V5 on multi-processors
(in response to Peter Lovelock)

I think best option today depends on what you do with CATIA.
But a good option is getting the fastest dual core you can get, as much ram as you can afford, fast HD, and WinXP64 (or you won't get any benefit from more than 3GB of RAM).

Eduardo

Roger Bombassei

RE: V5 on multi-processors
(in response to Peter Lovelock)
Eduardo,
I have to disagree with you when you say there is no benefit from using more than 3GB of RAM on a x64 machine.
Also, I would recommend multi core processors even if you can get a single core a little cheaper. Most of are bouncing around between multiple applications while at least one is crunching #s. You will definatly benefit from multi core or multi processors in that case.

Steven Kwok

RE: V5 on multi-processors
(in response to Peter Lovelock)
Roger,

I'm pretty sure Eduardo meant DO get x64 SO you CAN get a benefit from >3GB.

That being said, Last time I checked the fastest cores are part of dual cores. The new generation dual core Xeons are ridiculously fast on both cores, far faster than any single core machine individually, and you get the bonus of a secondary CPU for running other applications/background processes. Just make sure you get the new gen Xeons, not the old ones. They're expensive, but CATIA is mostly CPU dependent for performance (in design anyway, rendering is a different story, i suppose), and you'll get the biggest benefit there. To my knowledge, additional ram is useless unless you actually open up large enough models/assemblies to utilize it. Assuming CATIA isn't crashing out due to memory problems (or will soon), you simply need enough RAM.

That being said, I'm all for getting the nicest machine if you are at all concerned about performance. It's completely worth it to get the x64 machine with 8GB of RAM, the $3,000 Xeon Dual core processor with a solid workstation level graphics card, running 2+ monitors and a space navigator. The way I always look at it is with the following calculation:

If you save half an hour a day, at a rate (assuming 3x overhead on 33/hour) of $100/hour, 250 days a year, that's $12,500 worth of productivity. When I was sitting on my hands 20 minutes at a time running heavy updates on ultra heavily parametric models, then reduced that to 2 minutes (with the first gen core 2 duo, on a LAPTOP, from a 3.0 Xeon), yeah, you could say it was a solid purchase.

Roger Bombassei

RE: V5 on multi-processors
(in response to Peter Lovelock)

Opps, you are right Steve.  Sorry Eduardo.

I have a x64 dual Zeon Dell with dual 512 mb Nvidia Quadro graphics cards and SLI bridge and 8gb RAM.

CATIA NC is graphics demanding.

I bought my system from Dell Outlet and it was far less than $3000.

Ian Phillips

RE: V5 on multi-processors
(in response to Peter Lovelock)
There are so many cases where CATIA should be using multiple cores/processes but doesn't!
A big update, for example can update separate branches simultaneously.
Any long process with the progress bar should be able to cope with user interactions and not take ages to react to cancel.
Open 2 separate Catparts. Start one updating/saving/calculating and then work happily on the other one.
It is about time CATIA could do this. Nag Dassault to fix it!

Steven Kwok

RE: V5 on multi-processors
(in response to Peter Lovelock)
I'm no expert, but sad to say, the programming required to makes something multi-threaded is not a simple addition. You are right in that there ARE many simple ways to separate out distinct tasks (like separate parts updating). Sad to say that I merely open multiple sessions of CATIA in order to circumvent the update 'freeze out' that CATIA has, even though it only uses a single core. In fact, when I was working on a dual quad core machine I would run scripts on 8 separate instances of CATIA in order to make better use of the processor. At a certain point hard drive access becomes an issue, but it still ran a whole lot faster than a single session did, that's for sure. 4-5 times I think.

Ian Karges

RE: V5 on multi-processors
(in response to Peter Lovelock)
Just to complicate the issue a bit more, what about quad core processors compared to duo core? Is there any performance increase in Catia between the duo and quad cores? Typically we only update our workstations every 3 years so I tend to think buy the latest technolgy that the budget can support. There have been deals lately where you can purchase quad cores for the same if not less than the duo cores. Some of my colleges are concerned that the quad cores won't perform as well as the duo's. Specifically we were looking at 3ghz quad core vs a 3.33ghz duo core. Anyone had experience comparing the two?

Ian Karges
Volvo Construction Equipment
Canadian Operations
Engineering Systems Administrator

Derek Bezaire

RE: V5 on multi-processors
(in response to Peter Lovelock)
Ian - I find the order of importance 64bit OS, Ram, graphics card, Fast Scsi drive, processor. I deal with large tool designs with little calculations. We have switched from all IBM Zpro IntelliStations to Dell 690 (16GB Ram, FX4500 graphics, Scsi drives, Dual Core) with no complaints.

Regards,
Derek

Steven Kwok

RE: V5 on multi-processors
(in response to Peter Lovelock)

Ian, to answer your question, Quad will not give you ANY boost over Dual unless you are running an inordinate amount of background processes or are running 2+ full instances of CATIA on the same machine simultaneously. Different instances of CATIA WILL use different processors. I used to do this to make full use of a quad core machine, but I can't say that I advise it from a designing standpoint. From a coding standpoint, however, it makes perfect sense, since my codes could care less how many instances of CATIA I run. Therefore, I'd say, of course go for Dual over Quad, especially if the Duals have higher clock speeds (which they should). Keep in mind, clock speed isn't the only relevant factor. The same clock speed Dual Core Xeons new generation are 6x faster than the third generation Core 2 Duo E6850 (extremely popular consumer level cpu). For a nice benchmark chart you can check passmark:

http://www.cpubenchmark.net/high_end_cpus.html

To make the CATIA comparison, divide the quad core processors by 2 and leave the dual cores alone since CATIA only uses one core (there are no high end core solos, so we can safely ignore them).

CATIA results will vary, since this is pure CPU calculation speed, as best as I can tell, and CATIA relies heavily on CPU memory bandwidth, namely it's L1, L2, and possibly L3 cache sizes. Which is why a new generation Dual Core Xeon can smoke a old school Pentium Dual Core at the same clock speed by a factor of 100X, despite appearing to be the 'same speed', and both having two cores.

Interesting Derek, that is precisely the exact opposite order that is important to me. I tend to run high calculations on large numbers of simple parts. Therefore, my order of importance is a high quality Dual Core Xeon, 10K/15K raptor or solid state hard drives, Quadro graphics, and then RAM. To my knowledge CATIA uses the following:

All calculations, changes, updates use the CPU. You can monitor your CPU usage by keeping your task manager up. Anytime you see your processor at 100% usage (single core) 50% usage (dual core) or 25% usage (quad core), you are maxed out and would benefit from a faster CPU. For me, this is 80%+ of my wait time.

All load times are hard drive speed. When you see the hard drive light blink or you 'hear' your computer grinding, this is you waiting on the hard drive. This usually corresponds to relatively low CPU usage, therefore is easy to distinguish. Opening assemblies and/or catalogs tend to stress the hard drive. Drawings as well (when opening). This represents 20% or less of my wait time.

All display issues are a combination of graphics card and CPU speed. You'll notice that when you rotate a model, your CPU usage will spike (quite possibly to 100%). This is a shared event between your CPU and your GPU, but when you see "shaking", it's usually the GPU that's struggling, I believe. I believe this also applies to kinematics and all updates that are heavily visual based. Again, all shared with your CPU. I believe the faster your GPU, the less heavily it will rely on your CPU. Sometime in the next decade when we get CUDAs we can have direct hardware bridge this gap and have a single unit that does both, instead of relying on software bridges.

Finally, RAM speed is important, because CATIA pushes everything into RAM, except for the fact that most RAM is about the same speed when you buy a computer. Usually it's merely the quantity that changes. In this case, RAM does not effect performance, merely ability. If you run out of RAM CATIA will crash to desktop or give the "Click OK to terminate". More is not faster.

On the same note, I'm not sure what kind of performance differences you get with 32 vs 64 bit except that 64 bit enables a near unlimited amount of RAM (the physical limit is far far greater than what you can buy anyway). The maximum amount of data 32 bit CATIA can load into memory is about 2.6GB (on a 4GB machine with the /3GB switch enabled, without the /3GB switch it's about 1.7GB). 64 bit CATIA will continue cranking until you've physically maxed out your RAM chips, whether that be 16GB or 64GB. Aside from that, I've never done a straight test on performance between the two.

Hopefully this helps.

FAQ multi core dual quad performance ram hard drive graphics card slow fast computer purchase desktop laptop

Phil Harrison

RE: V5 on multi-processors
(in response to Peter Lovelock)
I know that none of use do drafting anymore(!) but I believe that it would be relatively easy for DS to enable multithreading such that each processor could do a view update or view generation/auto dimension generation.

This would yield a very significant performance improvement.

D Taylor

RE: V5 on multi-processors
(in response to Peter Lovelock)

Steven,

Just so I understand what you are saying about CPUs:

Are you saying that a CPU intensive task in (non-DMU)Catia would take the same amount of time to complete on a 3.0GHz Dual Core Intel® Xeon® Processor as on a 3.0GHzQuad Core Intel® Xeon® Processor? {assuming same L2 cache and FSB}

Derek Bezaire

RE: V5 on multi-processors
(in response to Peter Lovelock)
Taylord,
That is correct.

Regards,
Derek

COE Administrator

RE: V5 on multi-processors
(in response to Peter Lovelock)
As far as utilizing more CPU, we've had some good experience using the drawing update utility (Tools-Utility from V5) This launches a separate process, which means it can take advantage of another core. If there's a big drawing to update, the utility runs, and the user can keep going with an interactive V5 session, with little loss of performance.
~Joe