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Fluent simulation in parallel is slower on workstation than laptop?!!?!

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Old   December 14, 2019, 06:47
Default Fluent simulation in parallel is slower on workstation than laptop?!!?!
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Os
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Hello ,

I am making a 2D simulation using fluent

at first i run the simulation on my i7 laptop 2012 (4cores 8 threads) than i got a z820 workstation with 2 processores (24 cores 48 threads)and i run the exact same simulation on the workstation and i was schoked that it's only 2 times faster than my laptop.

the setting i chose for the laptop and workstation are :
1/-laptop -parallel -double precision -6 processors
2/-workstation - parallel -double precision -36 processors
How in the World that a workstation in only 2 times faster than my laptop ?!!
Do you have any idea about what may the problem be ?
PS:

1/-both the laptop and workstation have the same ansys version 2019 R3.both the simulations setting are the exact same except for the number of precessors used for parallel solving.


Many Thanks

Last edited by losiola; December 15, 2019 at 06:02.
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Old   December 14, 2019, 18:28
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Why should we help people that use cracked software? I pay a lot for support and think it is unfair if you don't. I hope you will have to pay as well when ANSYS traces you back via the internet.
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Old   December 15, 2019, 06:11
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Quote:
Originally Posted by Gert-Jan View Post
Why should we help people that use cracked software? I pay a lot for support and think it is unfair if you don't. I hope you will have to pay as well when ANSYS traces you back via the internet.
Yeah that True but where you come from and where i come from is totally different , you live where life is easy i live where i have to struggle to get just the little things of life .

Am sure you can afford the ansys licence let's say after 2-3 years salary (not sure even how much does it cost ) and get to drive a nice car and have a home get married , travel, enjoy life , For me i cant afford it even after 10-15 years (at least) of work and in case i could i wont be able to buy car nor home nor getting married and i'll be 10-15 more years older than i am . so yeah life is unfair

So i guess that the best thing to do is to just help people with their questions if you can . And always remember how lucky you are Compared to other people Around the World .

HAVE A GREAT DAY.

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Old   December 15, 2019, 09:28
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I have no idea where you come from, where you live, whatsoever. But you seem to have access to recent computers. So, you're not in the middle of nowhere. It could be that you are the guy next door.

If you compare the performance of single processors in a i7-laptop and a workstation, the laptop will win. The workstation will only beat the laptop if you run a large calculation in parallel over multiple processors. Before I buy a system, I always look at the performance on the passmark website. I can recommend this.
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Old   December 15, 2019, 10:02
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Quote:
Originally Posted by Gert-Jan View Post
I have no idea where you come from, where you live, whatsoever. But you seem to have access to recent computers. So, you're not in the middle of nowhere. It could be that you are the guy next door.

If you compare the performance of single processors in a i7-laptop and a workstation, the laptop will win. The workstation will only beat the laptop if you run a large calculation in parallel over multiple processors. Before I buy a system, I always look at the performance on the passmark website. I can recommend this.

Thanks for the Reply but i guess i ve found the problem which i believe , based on the topics i ve found , that it's due to the Hyperthreading i ve found that fluent performance is not affected (increased) by hyper threading ( at max 20 %) but on the other hand i ve found also that hyper threading slows dow the simulation so i ve disabled hyperthreading and i am going to use only the physical cores and post later the result.


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Old   November 4, 2022, 09:56
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Quote:
Originally Posted by losiola View Post
Thanks for the Reply but i guess i ve found the problem which i believe , based on the topics i ve found , that it's due to the Hyperthreading i ve found that fluent performance is not affected (increased) by hyper threading ( at max 20 %) but on the other hand i ve found also that hyper threading slows dow the simulation so i ve disabled hyperthreading and i am going to use only the physical cores and post later the result.


.
Hello, I have the same problem. I will be appreciated if you kindly post the results. Thank you.
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