Looks to me like it is a race condition, and the timing between 1.3.3 and 1.4 
is just enough to trip it. I can break the race, but it will have to be in a 
future fix release.

Meantime, your best bet is to either stick with 1.3.3 or add the delay.

On Dec 15, 2009, at 5:51 AM, Marcia Cristina Cera wrote:

> Hi,
> 
> I intend to develop an application using the MPI_Comm_spawn to create 
> dynamically new MPI tasks (or processes). 
> The structure of the program is like a tree: each node creates 2 new ones 
> until reaches a predefined number of levels.
> 
> I developed a small program to explain my problem as can be seen in 
> attachment.
> -- start.c: launches (through MPI_Comm_spawn, in which the argv has the level 
> value) the root of the tree (a ch_rec program). Afterward spawn, a message is 
> sent to  child and the process block in an MPI_Recv.
> -- ch_rec.c: gets its level value and receives the parent message, then if 
> its level is less than a predefined limit, it will creates 2 children: 
>         - set the level value;
>         - spawn 1 child;
>         - send a message;
>         - call an MPI_Irecv;
>         - repeat the 4 previous steps for the second child;
>         - call an MPI_Waitany waiting for children returns.
> When children messages are received, the process send a message to its parent 
> and call MPI_Finalize.
> 
> Using the openmpi-1.3.3 version the program runs as expected but with 
> openmpi-1.4 I get the following error:
> 
> $ mpirun -np 1 start
> level 0
> level = 1
> Parent sent: level 0 (pid:4279)
> level = 2
> Parent sent: level 1 (pid:4281)
> [xiru-8.portoalegre.grenoble.grid5000.fr:04278] [[42824,0],0] ORTE_ERROR_LOG: 
> Not found in file base/plm_base_launch_support.c at line 758
> 
> The error happens when my program try to launch the second child immediately 
> after the first spawn call. 
> In my tests I try to put an sleep of 2 second between the first and the 
> second spawn, and then the program runs as expected.
> 
> Some one can help me with this version 1.4 bug? 
> 
> thanks,
> márcia.
> 
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