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debugger hangs up

linfa
Beginner
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Hi

Hello, the following command hangs up on my machine

[linfa@testrun]$ mpirun -gdb -np 3 ../exec/mympiprogram
WARNING: Can't read mpd.hosts for list of hosts, start only on current



Howerver, this run doesn't hang up with the following command

[linfa@testrun]$ mpirun -trace -gdb -np 3 ../exec/mympiprogram
WARNING: Can't read mpd.hosts for list of hosts, start only on current
0: ERROR: ld.so: object 'libVT.so' from LD_PRELOAD cannot be preloaded: ignored.
2: ERROR: ld.so: object 'libVT.so' from LD_PRELOAD cannot be preloaded: ignored.
2: ERROR: ld.so: object 'libVT.so' from LD_PRELOAD cannot be preloaded: ignored.
0: ERROR: ld.so: object 'libVT.so' from LD_PRELOAD cannot be preloaded: ignored.
1: ERROR: ld.so: object 'libVT.so' from LD_PRELOAD cannot be preloaded: ignored.
1: ERROR: ld.so: object 'libVT.so' from LD_PRELOAD cannot be preloaded: ignored.
2: (gdb) 0-1: (gdb) quit
0-2: MPIGDB ENDING

Any ideas? Thanks.
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TimP
Honored Contributor III
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Sorry, I don't have a full answer, but the following suggestions:
The -trace option requests the debug MPI library, which might be helpful when you wish to debug. You might be able to get the same effect by setting LD_PRELOAD to the mpidbg library. Failure to find the trace .so calls into question your installation and mpivars setting for LD_LIBRARY_PATH, but may not stop you from proceeding.
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Dmitry_K_Intel2
Employee
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Hi linfa,

Please do not use -trace and -gdb option together.
-trace option is used to collect information about MPI communications in your program. Once you get a trace file you can analyze it in Intel Trace Analyzer (traceanalyzer). Of cause you need to have this product.
If you use -trace together with -gdb your trace files will be useless. Also trace library inserts own functions, so debugging of such application will be useless as well.

Regards!
Dmitry
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