PC appropriate equipment in order to run large ABAQUS job

[Zisis]

Dear all,

I have a question. Currently we are running 3D simulations using ABAQUS. Our current models consist of about 300000 DOF.
We are using PC's with dual core proccesors and 40Gb RAM with Vista. With this equipment the above job takes about 3 weeks.
We are using ABAQUS 32bit.

Could you please suggest a combination and the type of multiple proccesors together with the appropriate amount of memory that would substantially reduce the computational time?

Thanks in advance

Thanasis

 

[rstupplebeen]

More info is needed. What are your computer's stats? Do you have Vista 64bit? How much ram does the job use? How many tokens do you have. When pricing the computer keep in mind the cost of the software. I would suggest pooling the money together to create a GoTo box instead of each analyst having a hot box.

Rob Stupplebeen

 

[johnhors]

40Gb RAM on a 32bit machine - I don't think so !

As Rob suggested, migrate to a 64bit machine and OS running 64bit Abaqus, then you can make use of 40Gb of RAM

 

[barney75]

Zisis
as far as I know 32bit OS does not allow u to allocate the large amount of RAM that u have in your PC (40Gb). In particular, please correct me if I'm wrong, u can allocate (use) only 2^32 that corresponds to about 4Gb with 32bit OS (then u have to subtract the memory amount needed for the OS and any other running application) and 2^64 with 64bit OS.
I think that u are not using all the memory u have and first advice would be to change 32bit for 64bit OS.
Secondly consider that, according to my experience, most of the time spent in the analyses may be not related to CPU time (i.e. performing calculation) but to write results step by step or incerment by increment (obviously it strongly depends on the model). So another advice would be try to write as less as u need in order to reduce writing time or to buy Hard Disk with high rotation velocity for speed up writing phase.

See u

Barney

 

[Zisis]

Ofcourse you are right,

by mistake I typed 40Gb instead of 4Gb. The current OS is Vista 32bit.

So from what I read you suggest that I should first switch to vista 64bit and ABAQUS 64bit and then buy a fast Hard disk.

 

[rstupplebeen]

It really depends on the rest of your stats. If you are running a slow computer all around then it is probably not worth any further investment. If you post your CPU(s), HD speed, tokens.... then we could help. Basically right now we can't really help. If you post your INP some of us might be willing to run your model and tell you how fast it ran and what our computer's stats are. I know I won't run it unless you provide a comprehensive list of your stats as a starting point for benchmarking. Depending on your budget you might get the hardware seller to run you model for you or provide a demo unit to take through the paces. I hope this helps.

Rob Stupplebeen

Rob Stupplebeen

 

[bajsi]

The first thing to do is to start using linux 64 bit - it gives you 20% boost without any additional cost.

The second thing is it invest in more RAM and use ramdisk for scractch dir - it gives you additional 30% boost.

 

[johnhors]

The first thing to do is to start using linux 64 bit - it gives you 20% boost without any additional cost.

I presume you mean compared to windows 64bit (vista, XP or 7 ?), and what is "boost"?

I'm no fan of Microsoft, but what's this based on?

 

[bajsi]

By 20% boost I meant 20% less time needed to complete a calculation.

The choice of OS (lin/XP/Vista) is not that crucial but using 64 bit system is really worth it if you do a lot of computing.

I use linux mainly for two reasons:
- uses less RAM so there is more available for ABAQUS
- has built-in support for dynamic ramdisk to put scratch dir on

Our bencmarking of a geometric nonlinerar job:
XP SP2 32 : 25 min
Vista 64 : 21 min
Vista 64 RAM disk : 16 min
Ubuntu 8.10 64 RAM disk : 16 min

So lin/win perform equally well it is just that Vista eats 1GB of RAM and linux 200 MB.

 

[johnhors]

Okay, thanks for that.

A colleague of mine has done a fair amount of bench marking Abaqus on XP64 against linux64 and overal found little to choose between them (as you actually found as well!)