CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Fluent UDF and Scheme Programming

cell loop in parallel Fluent

Register Blogs Members List Search Today's Posts Mark Forums Read

Reply
 
LinkBack Thread Tools Display Modes
Old   August 16, 2013, 16:52
Default cell loop in parallel Fluent
  #1
Member
 
Join Date: Jul 2013
Posts: 70
Rep Power: 4
upeksa is on a distinguished road
Some of you may recognise the following parallel UDF from the UDF Manual of Fluent(I have deleted the comments):

#include "udf.h"
#define WALLID 3
DEFINE_ON_DEMAND(face_p_list)
{
#if !RP_HOST
face_t f;
Thread *tf;
Domain *domain;
real *p_array;
real x[ND_ND], (*x_array)[ND_ND];
int n_faces, i, j;
domain=Get_Domain(1);
tf=Lookup_Thread(domain, WALLID);
n_faces=THREAD_N_ELEMENTS_INT(tf);
#if RP_NODE
if(! I_AM_NODE_ZERO_P)
{
PRF_CSEND_INT(node_zero, &n_faces, 1, myid);
#endif
p_array=(real * )malloc(n_faces*sizeof(real));
x_array=(real (*)[ND_ND])malloc(ND_ND*n_faces*sizeof(real));
begin_f_loop(f, tf)
{
p_array[f] = F_P(f, tf);
F_CENTROID(x_array[f], f, tf);
}
end_f_loop(f, tf)
Message0("\nstart\n");
#if RP_NODE
if(! I_AM_NODE_ZERO_P)
{
PRF_CSEND_REAL(node_zero, p_array, n_faces, myid);
PRF_CSEND_REAL(node_zero, x_array[0], ND_ND*n_faces, myid);
}
else
#endif
{
Message0("\n\nList of Pressures...\n");
for(j=0; j<n_faces; j++)
{
# if RP_3D
Message0("%12.4e %12.4e %12.4e %12.4e\n",
x_array[j][0], x_array[j][1], x_array[j][2], p_array[j]);
# else /* 2D */
Message0("%12.4e %12.4e %12.4e\n",
x_array[j][0], x_array[j][1], p_array[j]);
# endif
}
}
#if RP_NODE
if(I_AM_NODE_ZERO_P)
{
compute_node_loop_not_zero(i)
{
PRF_CRECV_INT(i, &n_faces, 1, i);
p_array=(real *)realloc(p_array, n_faces*sizeof(real));
x_array=(real(*)[ND_ND])realloc(x_array,ND_ND*n_faces*sizeof(real));
PRF_CRECV_REAL(i, p_array, n_faces, i);
PRF_CRECV_REAL(i, x_array[0], ND_ND*n_faces, i);
for(j=0; j<n_faces; j++)
{
# if RP_3D
Message0("%12.4e %12.4e %12.4e %12.4e\n",
x_array[j][0], x_array[j][1], x_array[j][2], p_array[j]);
# else /* 2D */
Message0("%12.4e %12.4e %12.4e\n",
x_array[j][0], x_array[j][1], p_array[j]);
# endif
}
}
}
#endif /* RP_NODE */
free(p_array);
free(x_array);
#endif /* ! RP_HOST */
}

What I want to do is exactly the same, but instead of looping around the faces, I want to loop around the cell of the adjacent domain of a face given, so I changed that UDF to the following:

#include "udf.h"
#define WALLID 10025
DEFINE_ON_DEMAND(face_p_list)
{
#if !RP_HOST
face_t f;
cell_t c;
Thread *tf;
Thread *t0;
Domain *domain;
real *p_array;
real x[ND_ND], (*x_array)[ND_ND];
int n_cell, i, j;
domain=Get_Domain(1);
tf=Lookup_Thread(domain, WALLID);
t0=THREAD_T0(tf);
n_cell=THREAD_N_ELEMENTS_INT(t0);

#if RP_NODE
if(! I_AM_NODE_ZERO_P)
{
PRF_CSEND_INT(node_zero, &n_cell, 1, myid);
}
#endif

p_array=(real * )malloc(n_cell*sizeof(real));
x_array=(real (*)[ND_ND])malloc(ND_ND*n_cell*sizeof(real));
begin_c_loop(c, t0)

{
p_array[c] = C_P(c, t0);
F_CENTROID(x_array[f], f, tf);
}
end_c_loop(c, t0)

Message0("\nstart\n");
#if RP_NODE
if(! I_AM_NODE_ZERO_P)
{
PRF_CSEND_REAL(node_zero, p_array, n_cell, myid);
PRF_CSEND_REAL(node_zero, x_array[0], ND_ND*n_cell, myid);
}
else
#endif
{
Message0("\n\nList of Pressures...\n");

for(j=0; j<n_cell; j++)

{
# if RP_3D
Message0("%12.4e %12.4e %12.4e %12.4e\n",
x_array[j][0], x_array[j][1], x_array[j][2], p_array[j]);
# else /* 2D */
Message0("%12.4e %12.4e %12.4e\n",
x_array[j][0], x_array[j][1], p_array[j]);
# endif
}
}

#if RP_NODE
if(I_AM_NODE_ZERO_P)
{
compute_node_loop_not_zero(i)

{
PRF_CRECV_INT(i, &n_cell, 1, i);

p_array=(real *)realloc(p_array, n_cell*sizeof(real));
x_array=(real(*)[ND_ND])realloc(x_array,ND_ND*n_cell*sizeof(real));

PRF_CRECV_REAL(i, p_array, n_cell, i);
PRF_CRECV_REAL(i, x_array[0], ND_ND*n_cell, i);
for(j=0; j<n_cell; j++)
{
# if RP_3D
Message0("%12.4e %12.4e %12.4e %12.4e\n",
x_array[j][0], x_array[j][1], x_array[j][2], p_array[j]);
# else /* 2D */
Message0("%12.4e %12.4e %12.4e\n",
x_array[j][0], x_array[j][1], p_array[j]);
# endif
}
}
}
#endif /* RP_NODE */
free(p_array);
free(x_array);
#endif /* ! RP_HOST */
}

There are not any problem when I build of load that new UDF, but when I execute the demand, there is this message in the TUI:


999999 (..\src\mpsystem.c@1173): mpt_read: failed: errno = 10054

999999: mpt_read: error: read failed trying to read 4 bytes: No such file or directory
MPI Application rank 0 exited before MPI_Finalize() with status -1073741819
The Parallel FLUENT process could not be started.


¿Any ideas?
By the way, I have around 2000 faces and 50000 cell in each partition, ¿could that be a problem?

Thanks in advance, best regards.
upeksa is offline   Reply With Quote

Old   August 18, 2013, 04:10
Default
  #2
New Member
 
kornetka's Avatar
 
Join Date: Jun 2013
Posts: 15
Rep Power: 4
kornetka is on a distinguished road
Hi
I believe the problem may be in

begin_c_loop(c, t0)
{
p_array[c] = C_P(c, t0);
F_CENTROID(x_array[f], f, tf);
}
end_c_loop(c, t0)

In original example it is the face loop. Hope it helps. Btw, I have the feeling that sometimes when there is an error in the UDF, serial mode can describe it better than parallel mode, i.e. give better error message.

kornetka
kornetka is offline   Reply With Quote

Old   August 18, 2013, 08:31
Default
  #3
Member
 
Join Date: Jul 2013
Posts: 70
Rep Power: 4
upeksa is on a distinguished road
Quote:
Originally Posted by kornetka View Post
Hi
I believe the problem may be in

begin_c_loop(c, t0)
{
p_array[c] = C_P(c, t0);
F_CENTROID(x_array[f], f, tf);
}
end_c_loop(c, t0)

In original example it is the face loop. Hope it helps. Btw, I have the feeling that sometimes when there is an error in the UDF, serial mode can describe it better than parallel mode, i.e. give better error message.

kornetka
Thanks, you are absolutelly right, you have helped me a lot, I should have check that kinf of issues first.

Anyway, I correct it and I still have the same error massage. I changed the macro THREAD_N_ELEMENTS_INT for THREAD_N_ELEMENTS and I works now.

However, I am still not sure why it works with the macro PRF_CSEND_INT and PRF_CSEND_LONG, when in my case "n_cell" it is longer than 4 bytes.

I will do some further research and then I let everybody know just in case it helps.

Greetings, and thanks again.
upeksa is offline   Reply With Quote

Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
udf problem jane Fluent UDF and Scheme Programming 11 December 4, 2012 04:09
fluent parallel processing problem pedram.sotudeh FLUENT 0 June 19, 2012 01:32
Parallel FLUENT received fatal signal ramrocket FLUENT 3 April 30, 2012 03:19
Parallel Processing Problems Fluent 13 lstebe FLUENT 3 February 15, 2012 10:54
Fluent Parallel Error Will Humber FLUENT 2 April 3, 2008 14:15


All times are GMT -4. The time now is 21:38.