[parsec-users] extending input set for fluidanimate

Kirak Hong hokira at gatech.edu
Thu Mar 25 20:33:13 EDT 2010


Sorry, let me make my question clear.

If I have an input file containing 500 particles, is there any way to run
fluidanimate with particle numbers 1, 2, 3, ..., 500?

Thanks,
Kirak

On Thu, Mar 25, 2010 at 8:24 PM, Kirak Hong <hokira at gatech.edu> wrote:

> Hi,
>
> I wanted to have more input data to see different behaviors of fluidanimate
> regarding different inputs.
> So the possible solutions based on my understanding are :
>
> 1. clone particles (hack the input)
> 2. randomly generate particles
> 3. take inputs from outputs
>
> Is this true?
>
> If it is true, my problem now is that I don't know the input file format
> for fluidanimate. Could you tell me what's the input format and what program
> takes uses the ".fluid" files? I saw that it is from Intel RMS application,
> but I have no idea about that.
>
> Thanks!
> Kirak
>
> 2010/3/25 Jim Dempsey <jim at quickthreadprogramming.com>
>
>>  Chris, Kirak,
>>
>> For benchmarking I think the 500K is more than adequate for 1P or 2P
>> systems. 500K x 104 = ~50MB data. On 4P or 8P systems 500K particles could
>> fit in cache (at 12/24MB per processor). A larger data set would be
>> appropriate for these systems. I could see a need to generate 1M, 2M, 4M, 8M
>> and 16M particles. So I think a feature should be incorporated into
>> fluidanimate (or application added) whereby the domain dimensions, cell size
>> and and number of particles be specified, and then which will generate a
>> test data set.
>>
>> An alternate way to accomplish this auto-magically, would be for the
>> initial particle domain dimensions, cell size and particle count, be
>> duplicated/multiplied as an input option. The additional particle domains
>> would then be abutted together. Example,
>>
>> The 55 cell x 76 cell x 55 cell domain can be (by option) specified to be
>> doubled, thus producing
>> 110 cell by 76 cell x 55 cell particle domain, or quadrupled, thus
>> producing
>> 110 cell by 76 cell x 110 cell particle domain.
>>
>> The 76 cell Y is along the direction of gravity and would likely not need
>> to be extended.
>> The trailing options could be x, y, and z multipliers
>>
>> serial 1 0 in_500k.fluid in_2M.fluid 2 1 2
>>
>> Run Serial.exe, 1 thread, 0 frames, input file in_500k.fluid, output file
>> in_2M.fluid, dimension x doubled, dimension y unchanged, dimension z
>> doubled.
>>
>> Or the user could simply run with the multipliers and smaller input file
>>
>> This has as an additional benefit of being able to ship PARSEC with
>> smaller data files.
>>
>> Jim
>>
>>
>>  ------------------------------
>> *From:* parsec-users-bounces at lists.cs.princeton.edu [mailto:
>> parsec-users-bounces at lists.cs.princeton.edu] *On Behalf Of *Christian
>> Bienia
>> *Sent:* Thursday, March 25, 2010 3:40 PM
>>
>> *To:* 'PARSEC Users'
>> *Subject:* Re: [parsec-users] extending input set for fluidanimate
>>
>>  Kirak,
>>
>>
>>
>> Jim’s suggestion should give you a good input with not too much work.
>> Another approach would be to write a synthetic input generator that will
>> generate random inputs with any amount of particles. You need to vary the
>> initial position and velocity of the particles. You also must make sure that
>> particles start within the bounding box and do not initially move too fast,
>> otherwise the simulation will become numerically unstable. The upper bound
>> on the velocity is given by the grid size and the time step size.
>>
>>
>>
>> If you use significantly more particles you might want to consider to
>> increase the volume of the bounding box. The particles should fit in
>> comfortably.
>>
>>
>>
>> Why exactly do you want bigger inputs?
>>
>>
>>
>> - Chris
>>
>>
>>
>>
>>
>> *From:* parsec-users-bounces at lists.cs.princeton.edu [mailto:
>> parsec-users-bounces at lists.cs.princeton.edu] *On Behalf Of *Jim Dempsey
>> *Sent:* Thursday, March 25, 2010 3:48 PM
>> *To:* 'PARSEC Users'
>> *Subject:* Re: [parsec-users] extending input set for fluidanimate
>>
>>
>>
>> Kirak,
>>
>>
>>
>> More than 500K particles?
>>
>>
>>
>> If so, as a quick and dirty "hack", edit the SaveFile such that it doubles
>> the particle count and writes each particle twice. Run the in_500K.fluid in,
>> and write out in_1M.fluid. Repeat this to double the particle counts.
>> Probably it would be best to add an additional argument to specify the
>> multiplier (and so you do not have to remember to remove the"hack"). You
>> might want to add a randomizer to the point duplicator such that no two
>> particles come in at exactly the same position. You might want to keep the
>> replicated particles within a reasonably close position. Should the
>> resultant file cause an explosion in the particles (blast out of the bottom
>> of the domain well) you can use the display mode and let the simulation run
>> until it has quieted down somewhat (but not all the way). Then reset the
>> simulation without display to run to that frame number. The output file is
>> now a reasonable approximation of what you might want.
>>
>>
>>
>> Jim Dempsey.
>>
>>
>>  ------------------------------
>>
>> *From:* parsec-users-bounces at lists.cs.princeton.edu [mailto:
>> parsec-users-bounces at lists.cs.princeton.edu] *On Behalf Of *Kirak Hong
>> *Sent:* Thursday, March 25, 2010 2:35 PM
>> *To:* parsec-users at lists.cs.princeton.edu
>> *Subject:* [parsec-users] extending input set for fluidanimate
>>
>> Hi,
>>
>> I am trying to make more input data set for fluidanimate in parsec 2.1.
>> I tried to find out input format and how to generate extra input data, but
>> didn't find anything yet.
>> Has anybody tried this before? Any help would be highly appreciated!
>>
>> Thanks!
>> Kirak
>>
>> _______________________________________________
>> parsec-users mailing list
>>
>> parsec-users at lists.cs.princeton.edu
>> https://lists.cs.princeton.edu/mailman/listinfo/parsec-users
>>
>>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.cs.princeton.edu/pipermail/parsec-users/attachments/20100325/ce308cd6/attachment-0001.html>


More information about the parsec-users mailing list