Displaying reporting message in the console slows my simulation

muketa · January 31, 2017, 04:55

Hello everybody,

I noticed that setting reporting interval to 1 (i.e. displaying messages- about residuals and warnings about reveresed flow - in Fluent consolle for each iteration) slows a lot the simulation (in this case transient multiphase).

Is like if Fluent waste time showing that messages. I disabled warnings by setting solve/set/flow-warnings? to no and reporting interval to 100 and the simulation time decreased by a factor 4

.

I know that sounds strange but it's true

Has anyone noticed this before?

In my simulation that is transient Fluent still display a message every time step:

"Updating solution at time level N..."

and I'm guessing that message slows in turn the simulation...how can I disable that message too?

Thank you for your answers

KevinZ09 · January 31, 2017, 05:17

Can't you just change the value of "Reporting Interval" found on the "Run Calculation" panel?

muketa · January 31, 2017, 05:27

Quote:

Originally Posted by KevinZ09

Can't you just change the value of "Reporting Interval" found on the "Run Calculation" panel?

Yes I changed that but also if I set reporting interval to 100, still Fluent prints in the console a message( not every iteration) but every time step (I'm simulating a trnsient multiphase flow).

By the way have you ever noticed that printing messages to the console slows so much the simulation? Don't you feel that is a strange behaviour?

KevinZ09 · January 31, 2017, 05:56

I'm not sure you can have Fluent not calculate the residuals every time step but every N timesteps. I've never used that; only changed the Reporting Interval. You could always disable "Plot" and "Print to Console" in the monitors, but I don't think you'd want to do that. They do give valuable information.

As for the printing to screen and plotting slowing your simulation down, yes, I am aware of that. Hence the option of not having Fluent do it every iteration. Depending on how many monitors you have, and especially the type, it can be quite costly to calculate them. Especially integrals over large surfaces/volumes require quite a lot of calculations. Plus, if you're running in parallel, processing data requires overhead and communication, which always slows your simulation down.

January 31, 2017, 04:55	Displaying reporting message in the console slows my simulation	#1
muketa New Member Join Date: Jul 2009 Posts: 7 Rep Power: 16	Hello everybody, I noticed that setting reporting interval to 1 (i.e. displaying messages- about residuals and warnings about reveresed flow - in Fluent consolle for each iteration) slows a lot the simulation (in this case transient multiphase). Is like if Fluent waste time showing that messages. I disabled warnings by setting solve/set/flow-warnings? to no and reporting interval to 100 and the simulation time decreased by a factor 4 . I know that sounds strange but it's true Has anyone noticed this before? In my simulation that is transient Fluent still display a message every time step: "Updating solution at time level N..." and I'm guessing that message slows in turn the simulation...how can I disable that message too? Thank you for your answers

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January 31, 2017, 05:17		#2
KevinZ09 Senior Member Kevin Join Date: Dec 2016 Posts: 138 Rep Power: 9	Can't you just change the value of "Reporting Interval" found on the "Run Calculation" panel?

January 31, 2017, 05:56		#4
KevinZ09 Senior Member Kevin Join Date: Dec 2016 Posts: 138 Rep Power: 9	I'm not sure you can have Fluent not calculate the residuals every time step but every N timesteps. I've never used that; only changed the Reporting Interval. You could always disable "Plot" and "Print to Console" in the monitors, but I don't think you'd want to do that. They do give valuable information. As for the printing to screen and plotting slowing your simulation down, yes, I am aware of that. Hence the option of not having Fluent do it every iteration. Depending on how many monitors you have, and especially the type, it can be quite costly to calculate them. Especially integrals over large surfaces/volumes require quite a lot of calculations. Plus, if you're running in parallel, processing data requires overhead and communication, which always slows your simulation down.