ssd for calculations fem

[ilfrau]

hello to all
I would like to install a ssd from 64 or 128 gb to make us turn over the fem analysis of pro/mechanica.
I just don't have much experience with it.
I read that there are various parameters that indicate the speed in reading/writing large files and many small files.
despite this, these info on the various sites that sell often are not there and I do not even have the experience to know which "speed" would be indicated for my case.
Thank you.

 

[Fulvio Romano]

what advantages do you expect to get from a ssd and during what phase of the fem?

 

[TAURUS77]

Hello ilfrau!!
the question of our fulvio friend is correct but in addition you have to understand what kind of fem software you use, the output of the files you usually get (also by analogy with your colleagues who make fem).
according to my personal experience with ssd the benefits there are but before the ssd you have to have a good dose of ram to be able to load the matrices and not go in swap.
with thermomechanical simulations my colleague at the University of palermo obtained output of 10-15 gb ( ultrasound wave simulation study generated by a laser in a construction steel block).
1) 64 and 128gb are a few minimum 256gb, if you want a brand and a model I recommend the excellent and proven samsung 840 pro 256gb at about 175-200€.
It's not usually the ssd that solves your problems but all the workstation you work with: I give you an example the traditional ssd + hd coupling of good brand and speed often from a remarkable performance boost.
the ssd reads and writes much faster than a traditional hd and on the small files type 4k we are around 30-40mb/s reading and 60-80 in writing account the 1-2 mb/s at the max of the traditional hds.
I repeat again for the fem it takes a beautiful multicore cpu type i7 3820, 3930k, 3970k(too expensive about 950€), i7 3770k, i7 2700k so ram 16-32gb of good speed and latency 1600 mhz goes well (I recommend the ballistix tactical 1600 mhz timing 8-8-24)
I saw that the software is ansys (I don't know what version you use), ok ok also I worked there in its time with the 11 so if you work at home you don't have a license for the multicore and the cpus that I mentioned above do to you (in case you have to buy a cpu)
by curiosity post your computer work configuration.:smile::smile::smile:

 

[cacciatorino]

to me it happened to see code_aster make a lot of input/output on the disk when using certain solutors and certain functions, even with moderate ram loads. It's a special solutor work mode, which can benefit from using a solid-state disk.

 

[TAURUS77]

I gave a fast spulciata on the net and found these pdf links for ansys seem interesting and give some info regarding the use of ssd for the fem.
the first pdf states that "ssds helps dansys reduce elapsed time and scale better with multi core"

good reading
http://www.ansys.com/staticassets/a...tner/intel/ansys-14.5-intel-ssd-benchmark.pdf
http://www.ansys.com/staticassets/ansys/staticassets/event/conference/hpc-for-mechanical-ansys.pdf

 

[ilfrau]

Sorry but google mail put me, I don't know why, the automatic message that someone on the forum had responded to my post in the spam folder....

All right. .
fem software I use, for work, is pro/mechanica.
the This is what discussion is said that the use of the ssd helps a lot in case of swap.

you then also refer to the use of ramdisk.

mechanica, during some contact analysis, wrote to me, at every iteration, in the folder indicated to him for temporary files, about 10 gb of stuff.
each iteration lasted about 1 minute. . .

 

[TAURUS77]

Hi there!
If you can spend some money buy it the ssd that helps and not little. If you still find a pretty crucial m4 512gb could do for you.
post your hardware configuration so we realize the pros and cons of the whole machine

 

[ilfrau]

place the configuration of the new work pc:
- so: w7 pro
- intel(r) xeon(r) cpu e5-1620 0 @ 3.60ghz, 3601 mhz, 4 core, 8 logical processors
- 16 gb ram
- graphics card: nvidia picture k4000
- motherboard and hard disk I do not remember them, the hd is a ssd; but I am that of the workstation hp z620

the point is, by study, at home, I do some fem analysis and as I have the 5 year hdd maybe I change it...

 

[TAURUS77]

place the configuration of the new work pc:
- so: w7 pro
- intel(r) xeon(r) cpu e5-1620 0 @ 3.60ghz, 3601 mhz, 4 core, 8 logical processors
- 16 gb ram
- graphics card: nvidia picture k4000
- motherboard and hard disk I do not remember them, the hd is a ssd; but I am that of the workstation hp z620

the point is, by study, at home, I do some fem analysis and as I have the 5 year hdd maybe I change it...

Great configuration! !
with the ram you should be able to work up about 11-12 million degrees of freedom by removing the ram useful to the pc by operating system and other, the general rule should be 1gb of ram every million degrees of freedom.... if my memory still works :smile:
if you do many iterations it is not difficult to occupy even 20gb or more temp at a time (every type of analysis however makes history to itself and depends on various factors)
only for this reason I recommend in capacious ssd from at least 256gb on a price site I saw the samsung 840 pro 512gb at about 350€ consider that a little years ago I paid the corsair performance pro 256gb approximately 300€.
I don't know with what kind and size of pieces you work in analysis, with my old notebook riucivo to meshare a piece with 0.4mm tetrahedri getting 1.739.649 knots and 1.218.533 elements but it was a simple analysis of linear static type but it crashed for lack of ram I barely had 3.25 gb analysis only of ram needed about 7gb free and as it couldn't even go into swap all se not before
from what I understood you do contact analysis that are much more challenging than linear statics.
according to me and from what I see around many colleagues combine a ssd to a hd compartment (for those who can spend the velociraptor or a better choice the barcuda seagates to put in raid 0) capacious and fast to store the output files.

if your hd has 5 years of intense use will be worn if instead it is normal use can add it together with others.

 

[ilfrau]

interesting your observation on "1gb of rams every million degrees of freedom"I never heard of it or read it.
in any case I am in contact with some ptc technicians to "learn" how to set really well the parameters of mechanica, because around and on the ptc forum they feel different, but then they are not always okay and lack a true guide.. .
Who knows?